Exhibit 4.5


 


Executed in 21
Counterparts, No. 22.


 


SUPPLEMENTAL INDENTURE


 


DATED JUNE 1, 2008


 


UNION ELECTRIC  COMPANY


 


TO


 


THE BANK OF NEW YORK,

AS TRUSTEE


 






 


(SUPPLEMENTAL TO THE INDENTURE OF MORTGAGE AND DEED OF TRUST DATED JUNE
15, 1937, AS AMENDED, EXECUTED BY UNION ELECTRIC COMPANY TO THE BANK OF NEW
YORK, AS TRUSTEE)


 






 


First Mortgage
Bonds, Senior Notes

Series MM


 


This instrument
was prepared by Steven R. Sullivan, Esq., Senior Vice President, General
Counsel and Secretary of Union Electric Company, 1901 Chouteau Avenue, St.
Louis, Missouri  63103, (314) 554-2098.


 


	
  WHEN RECORDED 

  MAIL TO: 

   

  Gerald L. Waters 

  Union Electric Company 

  1901 Chouteau Avenue 

  St. Louis, MO 61303

  



 

















 


SUPPLEMENTAL INDENTURE,
dated the 1st day of June, Two thousand and eight (2008) made by and
between UNION ELECTRIC COMPANY, a corporation organized and existing under the
laws of the State of Missouri (hereinafter called the “Company”), party of the
first part, and The Bank of New York (successor trustee to Bank of America, National
Association, formerly Boatmen’s Trust Company), a bank existing under the laws
of the State of New York (hereinafter called the “Trustee”), as Trustee under
the Indenture of Mortgage and Deed of Trust dated June 15, 1937,
hereinafter mentioned, party of the second part:


 


WHEREAS, the Company has heretofore executed and
delivered to the Trustee its Indenture of Mortgage and Deed of Trust, dated June 15,
1937, as amended May 1, 1941, April 1, 1971, February 1, 1974, July 7,
1980, February 1, 2000 and August 15, 2002 (said Indenture of
Mortgage and Deed of Trust as so amended, being hereinafter referred to as the “Original
Indenture”), to secure the payment of the principal of and the interest (and
premium, if any) on all bonds at any time issued and outstanding thereunder,
and indentures supplemental thereto dated June 15, 1937, May 1, 1941,
March 17, 1942, April 13, 1945, April 27, 1945, October 1,
1945, April 11, 1947, April 13, 1949, September 13, 1950, December 1,
1950, September 20, 1951, May 1, 1952, March 1, 1954, May 1,
1955, August 31, 1955, April 1, 1956, July 1, 1956, August 1,
1957, February 1, 1958, March 1, 1958, November 5, 1958, March 16,
1959, June 24, 1959, December 11, 1959, August 17, 1960, September 1,
1960, October 24, 1960, June 30, 1961, July 1, 1961, August 9,
1962, September 30, 1963, November 1, 1963, March 12, 1965, April 1,
1965, April 14, 1966, May 1, 1966, February 17, 1967, March 1,
1967, February 19, 1968, March 15, 1968, August 21, 1968, April 7,
1969, May 1, 1969, September 12, 1969, October 1, 1969, March 26,
1970, April 1, 1970, June 12, 1970, January 1, 1971, April 1,
1971, September 15, 1971, December 3, 1973, February 1, 1974, April 25,
1974, February 3, 1975, March 1, 1975, June 11, 1975, May 12,
1976, August 16, 1976, April 26, 1977, October 15, 1977, November 7,
1977, December 1, 1977, August 1, 1978, October 12, 1979, November 1,
1979, July 7, 1980, August 1, 1980, August 20, 1980, February 1,
1981, October 8, 1981, August 27, 1982, September 1, 1982, December 15,
1982, March 1, 1983, June 21, 1984, December 12, 1984, June 11,
1985, March 1, 1986, May 1, 1986, May 1, 1990, December 1,
1991, December 4, 1991, January 1, 1992, September 30, 1992, October 1,
1992, December 1, 1992, February 1, 1993, February 18, 1993, May 1,
1993, August 1, 1993, October 1, 1993, January 1, 1994, February 1,
2000, August 15, 2002, March 5, 2003, April 1, 2003, July 15,
2003, October 1, 2003, February 1, 2004 (eight separate indentures
supplemental thereto), May 1, 2004, September 1, 2004, January 1,
2005, July 1, 2005, December 1, 2005, June 1, 2007 and April 1,
2008 respectively, have heretofore been entered into between the Company and
the Trustee; and


 


WHEREAS, Bonds have heretofore been issued by
the Company under the Original Indenture as follows:


 


(1)           $80,000,000 principal amount of First
Mortgage and Collateral Trust Bonds, 3 3/4% Series due 1962, all of which
have been redeemed prior to the date of the execution hereof;


 


(2)           $90,000,000 principal amount of First
Mortgage and Collateral Trust Bonds, 3 3/8% Series due 1971, which are
described in the Supplemental Indenture dated May 1, 1941 (hereinafter
called the “Supplemental Indenture of May 1, 1941”), all of which have
been paid at maturity prior to the date of the execution hereof;


 

















 


(3)           $13,000,000 principal amount of First
Mortgage and Collateral Trust Bonds, 2 3/4% Series due 1975 (herein called
the “Bonds of 1975 Series”), which are described in the Supplemental Indenture
dated October 1, 1945 (hereinafter called the “Supplemental Indenture of October 1,
1945”), all of which have been paid at maturity prior to the date of the
execution hereof;


 


(4)           $25,000,000 principal amount of First
Mortgage and Collateral Trust Bonds, 2 7/8% Series due 1980 (herein called
the “Bonds of 1980 Series”), which are described in the Supplemental Indenture
dated December 1, 1950 (hereinafter called the “Supplemental Indenture of December 1,
1950”), all of which have been paid at maturity prior to the date of the
execution hereof;


 


(5)           $30,000,000 principal amount of First
Mortgage and Collateral Trust Bonds, 3 1/4% Series due 1982 (herein called
the “Bonds of 1982 Series”), which are described in the Supplemental Indenture
dated May 1, 1952 (hereinafter called the “Supplemental Indenture of May 1,
1952”), all of which have been paid at maturity prior to the date of the
execution hereof;


 


(6)           $40,000,000 principal amount of First
Mortgage Bonds, 3 3/4% Series due 1986 (herein called the “Bonds of 1986
Series”), which are described in the Supplemental Indenture dated July 1,
1956 (hereinafter called the “Supplemental Indenture of July 1, 1956”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(7)           $35,000,000 principal amount of First
Mortgage Bonds, 4 3/8% Series due 1988 (herein called the “Bonds of 1988
Series”), which are described in the Supplemental Indenture dated March 1,
1958 (hereinafter called the “Supplemental Indenture of March 1, 1958”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(8)           $50,000,000 principal amount of First
Mortgage Bonds, 4 3/4% Series due 1990 (herein called the “Bonds of 1990
Series”), which are described in the Supplemental Indenture dated September 1,
1960 (hereinafter called the “Supplemental Indenture of September 1, 1960”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(9)           $30,000,000 principal amount of First
Mortgage Bonds, 4 3/4% Series due 1991 (herein called the “Bonds of 1991
Series”), which are described in the Supplemental Indenture dated July 1,
1961 (hereinafter called the “Supplemental Indenture of July 1, 1961”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(10)         $30,000,000 principal amount of First
Mortgage Bonds, 4 1/2% Series due 1993 (herein called the “Bonds of 1993
Series”), which are described in the Supplemental Indenture dated November 1,
1963 (hereinafter called the “Supplemental Indenture of November 1, 1963”),
all of which have been redeemed prior to the date of the execution hereof;


 


(11)         $35,000,000 principal amount of First
Mortgage Bonds, 4 1/2% Series due 1995 (herein called the “Bonds of 1995
Series”), which are described in the Supplemental Indenture dated April 1,
1965 (hereinafter called the “Supplemental Indenture of April 1, 1965”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


2

















 


(12)         $30,000,000 principal amount of First
Mortgage Bonds, 5 1/2% Series due 1996 (herein called the “Bonds of 1996
Series”), which are described in the Supplemental Indenture dated May 1,
1966 (hereinafter called the “Supplemental Indenture of May 1, 1966”), all
of which have been paid at maturity prior to the date of the execution hereof;


 


(13)         $40,000,000 principal amount of First
Mortgage Bonds, 5 1/2% Series due 1997 (herein called the “Bonds of 1997
Series”), which are described in the Supplemental Indenture dated March 1,
1967 (hereinafter called the “Supplemental Indenture of March 1, 1967”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(14)         $50,000,000 principal amount of First
Mortgage Bonds, 7% Series due 1998 (herein called the “Bonds of 1998
Series”), which are described in the Supplemental Indenture dated March 15,
1968 (hereinafter called the “Supplemental Indenture of March 15, 1968”),
all of which have been redeemed prior to the date of the execution hereof;


 


(15)         $35,000,000 principal amount of First
Mortgage Bonds, 7 3/8% Series due 1999 (herein called the “Bonds of May 1999
Series”), which are described in the Supplemental Indenture dated May 1,
1969 (hereinafter called the “Supplemental Indenture of May 1, 1969”), all
of which have been redeemed prior to the date of the execution hereof;


 


(16)         $40,000,000 principal amount of First
Mortgage Bonds, 8 1/4% Series due 1999 (herein called the “Bonds of October 1999
Series”), which are described in the Supplemental Indenture dated October 1,
1969 (hereinafter called the “Supplemental Indenture of October 1, 1969”),
all of which have been redeemed prior to the date of the execution hereof;


 


(17)         $100,000,000 principal amount of First
Mortgage Bonds, 9.95% Series due 1999 (herein called the “Bonds of November 1999
Series”), which are described in the Supplemental Indenture dated November 1,
1979 (hereinafter called the “Supplemental Indenture of November 1, 1979”),
all of which have been redeemed prior to the date of the execution hereof;


 


(18)         $60,000,000 principal amount of First
Mortgage Bonds, 9% Series due 2000 (herein called the “Bonds of 2000
Series”), which are described in the Supplemental Indenture dated April 1,
1970 (hereinafter called the “Supplemental Indenture of April 1, 1970”),
all of which have been redeemed prior to the date of the execution hereof;


 


(19)         $50,000,000 principal amount of First
Mortgage Bonds, 7 7/8% Series due 2001 (herein called the “Bonds of January 2001
Series”), which are described in the Supplemental Indenture dated January 1,
1971 (hereinafter called the “Supplemental Indenture of January 1, 1971”),
all of which have been redeemed prior to the date of the execution hereof;


 


(20)         $50,000,000 principal amount of First
Mortgage Bonds, 7 5/8% Series due 2001 (herein called the “Bonds of April 2001
Series”), which are described in the Supplemental Indenture dated April 1,
1971 (hereinafter called the “Supplemental 


 


3

















 


Indenture
of April 1, 1971”), all of which have been redeemed prior to the date of the
execution hereof;


 


(21)         $60,000,000 principal amount of First
Mortgage Bonds, 8 1/8% Series due 2001 (herein called the “Bonds of October 2001
Series”), which are described in the Supplemental Indenture dated September 15,
1971 (hereinafter called the “Supplemental Indenture of September 15, 1971”),
all of which have been redeemed prior to the date of the execution hereof;


 


(22)         $70,000,000 principal amount of First
Mortgage Bonds, 8 3/8% Series due 2004 (herein called the “Bonds of 2004
Series”), which are described in the Supplemental Indenture dated February 1,
1974 (hereinafter called the “Supplemental Indenture of February 1, 1974”),
all of which have been redeemed prior to the date of the execution hereof;


 


(23)         $70,000,000 principal amount of First
Mortgage Bonds, 10 1/2% Series due 2005 (herein called the “Bonds of 2005
Series”), which are described in the Supplemental Indenture dated March 1,
1975 (hereinafter called the “Supplemental Indenture of March 1, 1975”),
all of which have been redeemed prior to the date of the execution hereof;


 


(24)         $70,000,000 principal amount of First
Mortgage Bonds, 8 7/8% Series due 2006 (herein called the “Bonds of 2006
Series”), which are described in the Supplemental Indenture dated August 16,
1976 (hereinafter called the “Supplemental Indenture of August 16, 1976”),
all of which have been redeemed prior to the date of the execution hereof;


 


(25)         $27,085,000 principal amount of First
Mortgage Bonds, 5.80% Environmental Improvement Series 1977, which are
described in the Supplemental Indenture dated October 15, 1977
(hereinafter called the “Supplemental Indenture of October 15, 1977”), all
of which have been redeemed prior to the date of the execution hereof;


 


(26)         $60,000,000 principal amount of First
Mortgage Bonds, 8 5/8% Series due 2007 (herein called the “Bonds of 2007
Series”), which are described in the Supplemental Indenture dated December 1,
1977 (hereinafter called the “Supplemental Indenture of December 1, 1977”),
all of which have been redeemed prior to the date of the execution hereof;


 


(27)         $55,000,000 principal amount of First
Mortgage Bonds, 9.35% Series due 2008 (herein called the “Bonds of 2008
Series”), which are described in the Supplemental Indenture dated August 1,
1978 (hereinafter called the “Supplemental Indenture of August 1, 1978”),
all of which have been redeemed prior to the date of the execution hereof;


 


(28)         $60,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 1980, which are described
in the Supplemental Indenture dated August 1, 1980 (hereinafter called the
“Supplemental Indenture of August 1, 1980”), all of which have been
redeemed prior to the date of the execution hereof;


 


4

















 


(29)         $150,000,000 principal amount of First
Mortgage Bonds, 15 3/8% Series due 1991 (herein called the “Bonds of February 1991
Series”), which are described in the Supplemental Indenture dated February 1,
1981 (hereinafter called the “Supplemental Indenture of February 1, 1981”),
all of which have been redeemed prior to the date of the execution hereof;


 


(30)         $125,000,000 principal amount of First
Mortgage Bonds, 15% Series due 1992 (herein called the “Bonds of 1992
Series”), which are described in the Supplemental Indenture dated September 1,
1982 (hereinafter called the “Supplemental Indenture of September 1, 1982”),
all of which have been redeemed prior to the date of the execution hereof;


 


(31)         $100,000,000 principal amount of First
Mortgage Bonds, 13% Series due 2013 (herein called the “Bonds of 2013
Series”), which are described in the Supplemental Indenture dated March 1,
1983 (hereinafter called the “Supplemental Indenture of March 1, 1983”),
all of which have been redeemed prior to the date of the execution hereof;


 


(32)         $100,000,000 principal amount of First
Mortgage Bonds, 9 3/8% Series due 2016 (herein called the “Bonds of 2016
Series”), which are described in the Supplemental Indenture dated March 1,
1986 (hereinafter called the “Supplemental Indenture of March 1, 1986”),
all of which have been redeemed prior to the date of the execution hereof;


 


(33)         $100,000,000 principal amount of First
Mortgage Bonds, 8 7/8% Series due 1996 (herein called the “Bonds of 1996
Series”), which are described in the Supplemental Indenture dated May 1,
1986 (hereinafter called the “Supplemental Indenture of May 1, 1986”), all
of which have been redeemed prior to the date of the execution hereof;


 


(34)         $60,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 1990A, which are
described in the Supplemental Indenture dated May 1, 1990 (hereinafter
called the “Supplemental Indenture of May 1, 1990”), all of which have
been redeemed prior to the date of the execution hereof;


 


(35)         $125,000,000 principal amount of First
Mortgage Bonds, 8 3/4% Series due 2021 (herein called the “Bonds of 2021
Series”), which are described in the Supplemental Indenture dated December 1,
1991 (hereinafter called the “Supplemental Indenture of December 1, 1991”),
all of which have been redeemed prior to the date of the execution hereof;


 


(36)         $75,000,000 principal amount of First
Mortgage Bonds, 8.33% Series due 2002 (herein called the “Bonds of 2002
Series”), which are described in the Supplemental Indenture dated December 4,
1991 (hereinafter called the “Supplemental Indenture of December 4, 1991”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(37)         $100,000,000 principal amount of First
Mortgage Bonds, 7.65% Series due 2003 (herein called the “Bonds of 2003 Series”),
which are described in the Supplemental Indenture dated January 1, 1992
(hereinafter called the “Supplemental 


 


5

















 


Indenture
of January 1, 1992”), all of which have been paid at maturity prior to the
date of the execution hereof;


 


(38)         $204,000,000 aggregate principal amount
of First Mortgage Bonds, consisting of $100,000,000 principal amount of 6 3/4% Series due
1999 and $104,000,000 principal amount of 8 1/4% Series due 2022 (herein
called the “Bonds of 1999 Series” and “Bonds of 2022 Series”, respectively),
which are described in the Supplemental Indenture dated October 1, 1992
(hereinafter called the “Supplemental Indenture of October 1, 1992”), of
which the Bonds of 1999 Series have been paid at maturity prior to the
date of execution hereof and the Bonds of 2022 Series have been redeemed
prior to the date of the execution hereof;


 


(39)         $170,000,000 aggregate principal amount
of First Mortgage Bonds, consisting of $85,000,000 principal amount of 7 3/8% Series due
2004 and $85,000,000 principal amount of 8% Series due 2022 (herein called
the “Bonds of December 2004 Series” and “Bonds of December 2022
Series”, respectively, which are described in the Supplemental Indenture dated December 1,
1992, (hereinafter called the “Supplemental Indenture of December 1, 1992”),
of which the Bonds of December 2022 Series have been redeemed prior
to the date of the execution hereof  and
the Bonds of December 2004 Series have been paid at maturity prior to
the date of the execution hereof;


 


(40)         $188,000,000 principal amount of First
Mortgage Bonds, 6 7/8% Series due 2004 (herein called the “Bonds of August 2004
Series”), which are described in the Supplemental Indenture dated February 1,
1993 (hereinafter called the “Supplemental Indenture of February 1, 1993”),
all of which have been paid at maturity prior to the date of the execution
hereof;


 


(41)         $148,000,000 principal amount of First
Mortgage Bonds, 6 3/4% Series due 2008 (herein called the “Bonds of May 2008
Series”), which are described in the Supplemental Indenture dated May 1,
1993 (hereinafter called the “Supplemental Indenture of May 1, 1993”), all
of which have been paid at maturity prior to the date of the execution hereof;


 


(42)         $75,000,000 principal amount of First
Mortgage Bonds, 7.15% Series due 2023 (herein called the “Bonds of 2023
Series”), which are described in the Supplemental Indenture dated August 1,
1993 (hereinafter called the “Supplemental Indenture of August 1, 1993”),
all of which have been redeemed prior to the date of the execution hereof;


 


(43)         $44,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 1993 (herein called the “Bonds
of 2028 Series”), which are described in the Supplemental Indenture dated October 1,
1993 (hereinafter called the “Supplemental Indenture of October 1, 1993”),
all of which are outstanding at the date of the execution hereof;


 


(44)         $100,000,000 principal amount of First
Mortgage Bonds, 7% Series due 2024 (herein called the “Bonds of 2024
Series”), which are described in the Supplemental Indenture dated January 1,
1994 (hereinafter called the “Supplemental Indenture of January 1, 1994”),
all of which have been redeemed prior to the date of the execution hereof;


 


6

















 


(45)         $173,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series AA (herein called the “Bonds of 2012
Series”), which are described in the Supplemental Indenture dated August 15,
2002 (hereinafter called the “Supplemental Indenture of August 15, 2002”),
all of which are outstanding at the date of the execution hereof;


 


(46)         $184,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series BB (herein called the “Bonds of 2034
Series”), which are described in the Supplemental Indenture dated March 5,
2003 (hereinafter called the “Supplemental Indenture of March 5, 2003”),
all of which are outstanding at the date of the execution hereof;


 


(47)         $114,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series CC (herein called the “Bonds of 2015
Series”), which are described in the Supplemental Indenture dated April 1,
2003 (hereinafter called the “Supplemental Indenture of April 1, 2003”),
all of which are outstanding at the date of the execution hereof;


 


(48)         $200,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series DD (herein called the “Bonds of 2018
Series”), which are described in the Supplemental Indenture dated July 15,
2003 (hereinafter called the “Supplemental Indenture of July 15, 2003”),
all of which are outstanding at the date of the execution hereof;


 


(49)         $200,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series EE (herein called the “Bonds of 2013
Series”), which are described in the Supplemental Indenture dated October 1,
2003 (hereinafter called the “Supplemental Indenture of October 1, 2003”),
all of which are outstanding at the date of the execution hereof;


 


(50)         $60,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004A, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004A Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(51)         $50,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004B, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004B Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(52)         $50,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004C, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004C Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(53)         $63,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004D, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004D Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


7

















 


(54)         $63,500,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004E, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004E Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(55)         $60,000,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004F, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004F Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(56)         $42,585,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004G, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004G Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(57)         $47,500,000 principal amount of First
Mortgage Bonds, Environmental Improvement Series 2004H, which are
described in the Supplemental Indenture dated February 1, 2004
(hereinafter called the “Series 2004H Supplemental Indenture of February 1,
2004”), all of which are outstanding at the date of the execution hereof;


 


(58)         $104,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series FF (herein called the “Bonds of 2014
Series”), which are described in the Supplemental Indenture dated May 1,
2004 (hereinafter called the “Supplemental Indenture of May 1, 2004”), all
of which are outstanding at the date of the execution hereof;


 


(59)         $300,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series GG (herein called the “Bonds of 2019
Series”), which are described in the Supplemental Indenture dated September 1,
2004 (hereinafter called the “Supplemental Indenture of September 1, 2004”),
all of which are outstanding at the date of the execution hereof;


 


(60)         $85,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series HH (herein called the “Bonds of 2020
Series”), which are described in the Supplemental Indenture dated January 1,
2005 (hereinafter called the “Supplemental Indenture of January 1, 2005”),
all of which are outstanding at the date of the execution hereof;


 


(61)         $300,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series II (herein called the “Bonds of 2037
Series”), which are described in the Supplemental Indenture dated July 1,
2005 (hereinafter called the “Supplemental Indenture of July 1, 2005”),
all of which are outstanding at the date of the execution hereof;


 


(62)         $260,000,000 principal amount of First
Mortgage Bonds, Senior Notes Series JJ (herein called the “Bonds of 2016
Series”), which are described in the Supplemental Indenture dated December 1,
2005 (hereinafter called the “Supplemental Indenture of December 1, 2005”),
all of which are outstanding at the date of the execution hereof;


 


8

















 


(63)         $425,000,000 principal amount  of First Mortgage Bonds, Senior Notes, Series KK
(herein called the “Bonds of 2017 Series”), which are described in the
Supplemental Indenture dated June 1, 2007 (hereinafter called the “Supplemental
Indenture of June 1, 2007”), all of which are outstanding at the date of
the execution hereof; and


 


(64)         $250,000,000 principal amount of First
Mortgage Bonds, Senior Notes, Series LL (herein called the “Bonds of 2018
Series”), which are described in the Supplemental Indenture dated April 1,
2008 (hereinafter called the “Supplemental Indenture of April 1, 2008”), all
of which are outstanding at the date of the execution hereof;


 


and


 


WHEREAS, the Company on August 31, 1955
acquired all of the properties of Union Electric Power Company, the Subsidiary
as defined in Article I of the Original Indenture, upon the dissolution of
the Subsidiary; the Company, by Supplemental Indenture dated August 31,
1955, conveyed all of the properties so acquired (other than property of the
character defined as excepted property in the granting clauses of the Original
Indenture) to the Trustee upon the terms and trusts in the Original Indenture
and the indentures supplemental thereto set forth for the equal and
proportionate benefit and security of all present and future holders of the
Bonds and coupons issued and to be issued thereunder, all the shares of stock
of the Subsidiary were released from the lien of the Original Indenture; and
the Company became entitled to change the general designation of the Bonds so
as to omit the words “and Collateral Trust”; and


 


WHEREAS, the Articles of Incorporation of the
Company were duly amended on April 23, 1956, to change its corporate name
from “Union Electric Company of Missouri” to “Union Electric Company”; and


 


WHEREAS, the Articles of Agreement of the
Trustee were duly amended effective on January 4, 1982 to change its
corporate name from “St. Louis Union Trust Company” to “Centerre Trust Company
of St. Louis”, and further amended on December 9, 1988, to change its
corporate name from “Centerre Trust Company of St. Louis” to “Boatmen’s Trust
Company”; and


 


WHEREAS, that on March 13, 1998, Boatmen’s
Trust Company merged into NationsBank, National Association and effective July 5,
1999, changed its name to Bank of America, National Association; and


 


WHEREAS, that on February 1, 2000, The Bank
of New York, as transferee of the corporate trust business of Bank of America,
National Association (formerly known as Boatmen’s Trust Company), Trustee under
the Original Indenture, became successor Trustee under the Original Indenture;
and


 


WHEREAS, the Company is entitled at this time to
have authenticated and delivered additional Bonds on the basis of “property
additions” upon compliance with and pursuant to the provisions of Section 4
of Article III of the Original Indenture; and


 


9
















 


WHEREAS,
the Company has entered into an Indenture dated as of August 15, 2002 (the
“Senior Note Indenture”) with The Bank of New York, as trustee (the “Senior
Note Trustee”) providing for the issuance from time to time of senior notes
thereunder; and


 


WHEREAS,
the Company desires by this Supplemental Indenture to provide for the creation
of, and the issuance to the Senior Note Trustee of, a new series of Bonds under
the Original Indenture as security for $450,000,000 aggregate principal amount
of the Company’s 6.70% Senior Secured Notes due 2019 (the “Senior Notes”) to be
issued under the Senior Note Indenture, to have the designation provided in Article I,
Section 1 hereof (herein called the “New Bonds”), and the Original
Indenture provides that certain terms and provisions, as determined by the
Board of Directors of the Company, of the Bonds of any particular series may be
expressed in and provided by the execution of an appropriate supplemental
indenture; and


 


WHEREAS,
the Original Indenture provides that the Company and the Trustee may enter into
indentures supplemental to the Original Indenture specifically to convey,
transfer and assign to the Trustee and to subject to the lien of the Original
Indenture additional properties acquired by the Company; and


 


WHEREAS,
the Company, in the exercise of the powers and authority conferred upon and
reserved to it under the provisions of the Original Indenture and pursuant to
appropriate resolutions of the Board of Directors, has duly resolved and
determined to make, execute and deliver to the Trustee a Supplemental Indenture
in the form hereof for the purposes herein provided; and


 


WHEREAS,
all conditions and requirements necessary to make this Supplemental Indenture a
valid, binding and legal instrument have been done, performed and fulfilled and
the execution and delivery hereof have been in all respects duly authorized;


 


NOW,
THEREFORE, THIS INDENTURE WITNESSETH:


 


That, in consideration of
the premises and of the mutual covenants herein contained and of the acceptance
of this trust by the Trustee and of the sum of One Dollar duly paid by the
Trustee to the Company at or before the time of the execution of this
Supplemental Indenture, and of other valuable considerations, the receipt
whereof is hereby acknowledged, and in order further to secure the payment of
the principal of and interest (and premium, if any) on all Bonds at any time
issued and outstanding under the Original Indenture, according to their tenor
and effect, and to secure the Senior Notes, the Company has executed and
delivered this Supplemental Indenture and has granted, bargained, sold,
warranted, aliened, remised, released, conveyed, assigned, transferred,
mortgaged, pledged, set over and confirmed and by these presents does grant,
bargain, sell, warrant, alien, remise, release, convey, assign, transfer,
mortgage, pledge, set over and confirm unto The Bank of New York, as Trustee,
and to its successors in trust under the Original Indenture forever, all and
singular the following described properties (in addition to all other
properties heretofore subjected to the lien of the Original Indenture and not
heretofore released from the lien thereof) - that is to say:


 


FIRST.


 


ALL power houses, plants,
buildings and other structures, dams, dam sites, substations, heating plants,
gas works, holders and tanks, together with all and singular the electric,
heating, gas and mechanical appliances appurtenant thereto of every nature
whatsoever, now owned by 


 


10

















 


the Company,
including all and singular the machinery, engines, boilers, furnaces,
generators, dynamos, turbines and motors, and all and every character of
mechanical appliance for generating or producing electricity, steam, gas and
other agencies for light, heat, cold, or power or other purposes, and all
transmission and distribution systems used for the transmission and
distribution of electricity, steam, gas and other agencies for light, heat,
cold or power or any other purpose whatsoever, whether underground or overhead,
surface or otherwise, now owned by the Company, including all poles, towers,
posts, wires, cables, conduits, manholes, mains, pipes, tubes, drains,
furnaces, switchboards, transformers, conductors, insulators, supports, meters,
lamps, fuses, junction boxes, regulator stations, and other electric, steam and
gas fixtures and apparatus; all of the aforementioned property being located in
the City of St. Louis, the counties of Adair, Audrain, Benton, Bollinger,
Boone, Butler, Caldwell, Callaway, Camden, Cape Girardeau, Clark, Clay,
Clinton, Cole, Cooper, Crawford, Daviess, Dunklin, Franklin, Gasconade, Howard,
Iron, Jefferson, Knox, Lewis, Lincoln, Livingston, Macon, Madison, Maries,
Marion, Miller, Mississippi, Moniteau, Montgomery, Morgan, New Madrid, Osage,
Pemiscot, Perry, Pettis, Phelps, Pike, Pulaski, Ralls, Randolph, Ray, Reynolds,
Ripley, St. Charles, St. Francois, Ste. Genevieve, St. Louis, Saline, Schuyler,
Scott, Stoddard, Warren, Washington, and Wayne, Missouri, the counties of Clay,
Hancock, Henderson, Madison, Marion, Perry, Piatt and St. Clair, Illinois, and
the counties of Des Moines, Henry, Johnson, Lee, and Washington, Iowa, upon
real estate owned by the Company, or occupied by it under rights to so occupy,
which real estate is described in, or added through the provisions of, the
Indenture of Mortgage and Deed of Trust dated June 15, 1937, the
Supplemental Indentures dated May 1, 1941, March 17, 1942, April 13,
1945, April 27, 1945, October 1, 1945, April 11, 1947, April 13,
1949, September 13, 1950, December 1, 1950, September 20, 1951, May 1,
1952, March 1, 1954, May 1, 1955, August 31, 1955, April 1,
1956, July 1, 1956, August 1, 1957, February 1, 1958, March 1,
1958, November 5, 1958, March 16, 1959, June 24, 1959, December 11,
1959, August 17, 1960, September 1, 1960, October 24, 1960, June 30,
1961, July 1, 1961, August 9, 1962, September 30, 1963, November 1,
1963, March 12, 1965, April 1, 1965, April 14, 1966, May 1,
1966, February 17, 1967, March 1, 1967, February 19, 1968, March 15,
1968, August 21, 1968, April 7, 1969, May 1, 1969, September 12,
1969, October 1, 1969, March 26, 1970, April 1, 1970, June 12,
1970, January 1, 1971, April 1, 1971, September 15, 1971, December 3,
1973, February 1, 1974, April 25, 1974, February 3, 1975, March 1,
1975, June 11, 1975, May 12, 1976, August 16, 1976, April 26,
1977, October 15, 1977, November 7, 1977, December 1, 1977, August 1,
1978, October 12, 1979, November 1, 1979, July 7, 1980, August 1,
1980, August 20, 1980, February 1, 1981, October 8, 1981, August 27,
1982, September 1, 1982, December 15, 1982, March 1, 1983, June 21,
1984, December 12, 1984, June 11, 1985, March 1, 1986, May 1,
1986, May 1, 1990, December 1, 1991, December 4, 1991, January 1,
1992, September 30, 1992, October 1, 1992, December 1, 1992, February 1,
1993, February 18, 1993, May 1, 1993, August 1, 1993, October 1,
1993, January 1, 1994, February 1, 2000, August 15, 2002, March 5,
2003, April 1, 2003, July 15, 2003, October 1, 2003, February 1,
2004 (eight separate supplemental indentures), May 1, 2004, September 1,
2004, January 1, 2005, July 1, 2005, December 1, 2005, June 1,
2007, April 1, 2008 and this Supplemental Indenture, or attached to or
connected with such real estate or transmission or distribution systems of the
Company leading from or into such real estate.


 


SECOND.


 


ALSO,
(except as in the Original Indenture expressly excepted) all franchises and all
permits, ordinances, easements, privileges, immunities and licenses, all rights
to construct, maintain and operate overhead, surface and underground systems
for the distribution and 


 


11

















 


transmission of
electricity, steam, gas or other agencies for the supply to itself or others of
light, heat, cold or power, all rights-of-way, all waters, water rights and
flowage rights and all grants and consents, now owned or, subject to the
provisions of Article XII of the Original Indenture, which it may
hereafter acquire.


 


ALSO,
(except as in the Original Indenture expressly excepted) all inventions, patent
rights and licenses of every kind now owned by the Company or, subject to the
provisions of Article XII of the Original Indenture, which it may
hereafter acquire.


 


THIRD.


 


ALSO,
subject to the provisions of Article XII of the Original Indenture, all
other property, real, personal and mixed (except as therein or herein expressly
excepted) of every nature and kind and wheresoever situated now or hereafter
possessed by or belonging to the Company, or to which it is now, or may at any
time hereafter be, in any manner entitled at law or in equity.


 


TO HAVE
AND TO HOLD all said properties, real, personal and mixed,
mortgaged, pledged and conveyed by the Company as aforesaid, or intended so to
be, unto the Trustee and its successors and assigns forever;


 


SUBJECT,
HOWEVER, to the exceptions and reservations and matters
hereinabove recited, to existing leases, to existing liens upon rights of way
for transmission or distribution line purposes, as defined in Article I of
the Original Indenture, and any extensions thereof, and subject to existing
easements for streets, alleys, highways, rights-of-way and railroad purposes
over, upon and across certain of the property hereinbefore described, and
subject also to all the terms, conditions, agreements, covenants, exceptions
and reservations expressed or provided in the deeds or other instruments
respectively under and by virtue of which the Company acquired the properties
hereinabove described, and to undetermined liens and charges, if any,
incidental to construction or other existing permitted liens as defined in Article I
of the Original Indenture;


 


IN TRUST,
NEVERTHELESS, upon the terms and trusts in the Original
Indenture and the indentures supplemental thereto, including this Supplemental
Indenture, set forth, for the equal and proportionate benefit and security of
all present and future holders of the Bonds and coupons issued and to be issued
thereunder, or any of them, without preference of any of said Bonds and coupons
of any particular series over the Bonds and coupons of any other series, by
reason of priority in the time of the issue, sale or negotiation thereof, or by
reason of the purpose of issue or otherwise howsoever, except as otherwise
provided in Section 2 of Article IV of the Original Indenture.


 


AND IT IS
HEREBY COVENANTED, DECLARED AND AGREED, by and between the
parties hereto, for the benefit of those who shall hold the Bonds and coupons,
or any of them to be issued under the Original Indenture, as follows:


 


ARTICLE I


 


DESCRIPTION OF THE NEW
BONDS


 


Section 1.               There
is hereby created a new series of Bonds to be executed, authenticated and
delivered under and secured by the Original Indenture which shall, subject to 


 


12

















 


the provisions of Section 1
of Article II of the Original Indenture, be designated as “First Mortgage
Bonds, Senior Notes Series MM” (the “New Bonds”) of the Company.  The New Bonds shall be executed,
authenticated and delivered in accordance with the provisions of, and shall in
all respects be subject to all of the terms, conditions and covenants of, the
Original Indenture and shall be issued to, and registered in the name of, the
Senior Note Trustee under the Senior Note Indenture to secure any and all
obligations of the Company under the Senior Notes and any other series of
senior notes from time to time outstanding under the Senior Note Indenture.


 


The New Bonds shall
mature on February 1, 2019, and shall bear interest at the rate per annum
set forth in the form of the New Bond contained in Section 3 of this Article I,
payable semi-annually on the 1st day of February and the 1st
day of August in each year, commencing on February 1, 2009, and at
maturity.  The New Bonds shall be payable
as to principal and interest in any coin or currency of the United States of
America which at the time of payment is legal tender for public and private
debts, and shall be payable, in immediately available funds, at the office of
the Senior Note Trustee.


 


Section 2.               The New Bonds shall not be
assignable or transferable except as permitted or required by Section 4.04
of the Senior Note Indenture.  Any such
transfer shall be effected at the principal office or place of business of the
Trustee under the Original Indenture. 
The New Bonds are exchangeable for the New Bonds of other denominations,
as in the Original Indenture provided, except that payment of a service charge
therefor will not be required by the Company.


 


Notwithstanding the
provisions of Section 6 of Article II of the Original Indenture, the
New Bonds shall be dated the date of authentication and shall bear interest
from the interest payment date to which interest on the New Bonds has been paid
next preceding the date thereof, unless such date is an interest payment date
to which interest has been paid, in which case they shall bear interest from
the date thereof, or unless the date thereof is prior to February 1, 2009,
in which case they shall bear interest from June 19, 2008; provided,
however, that, subject to the provisions of this Section with respect to
failure by the Company to pay any interest on an interest payment date, the
holder of any New Bond dated after a record date (as hereinafter defined) for
the payment of interest and prior to the date of payment of such interest shall
not be entitled to payment of such interest and shall have no claim against the
Company with respect thereto.


 


The person in whose name
any New Bond is registered at the close of business on any record date with
respect to any interest payment date shall be entitled to receive the interest
payable on such interest payment date notwithstanding the cancellation of such
Bond upon any transfer or exchange thereof subsequent to the record date and
prior to such interest payment date, except if and to the extent the Company
shall default in the payment of the interest due on such interest payment date,
in which case such defaulted interest shall be paid to the person in whose name
such Bond is registered on the date of payment of such defaulted interest or on
a subsequent record date for such payment if one shall have been established as
hereinafter provided.  A subsequent
record date may be established by the Company by notice mailed to the holders
of the New Bonds not less than ten days preceding such record date, which
record date shall be not more than thirty days prior to the subsequent interest
payment date.  The term “record date” as
used in this Section with respect to any regular interest payment date
shall mean the January 15 or July 15, as the case may be, next
preceding such interest payment date, or, if such January 15 or July 15
shall be a legal holiday in the State of New York or in the State of Missouri
or a day on which banking institutions in the Borough of Manhattan, The City of
New 


 


13

















 


York, or the City
of St. Louis, Missouri, are authorized by law to close, the next preceding day
which shall not be a legal holiday or a day on which such institutions are so
authorized to close.


 


Upon
any payment of the principal of, premium, if any, and interest on, all or any
portion of the Senior Notes, whether at maturity or prior to maturity by
redemption or otherwise or upon provision for the payment thereof having been
made in accordance with Section 5.01(a) of the Senior Note Indenture,
the New Bonds in a principal amount equal to the principal amount of such
Senior Notes shall, to the extent of such payment of principal, premium, if
any, and interest, be deemed paid and the obligation of the Company thereunder
to make such payment shall be discharged to such extent and, in the case of the
payment of principal (and premium, if any), such New Bonds shall be surrendered
to the Company for cancellation as provided in Section 4.08 of the Senior
Note Indenture. The Trustee may at any time and all times conclusively assume
that the obligation of the Company to make payments with respect to the
principal of, premium, if any, and interest on the Senior Notes, so far as such
payments at the time have become due, has been fully satisfied and discharged
pursuant to the foregoing sentence unless and until the Trustee shall have
received a written notice from the Senior Note Trustee signed by one of its
officers stating (i) the timely payment of principal, or premium, if any,
or interest on, the Senior Notes has not been made, (ii) that the Company
is in arrears as to the payments required to be made by it to the Senior Note
Trustee pursuant to the Senior Note Indenture, and (iii) the amount of the
arrearage.


 


Section 3.               The
New Bonds and the Trustee’s certificate on the New Bonds shall be substantially
in the following forms respectively:


 


[FORM OF FACE OF NEW BOND]


 


	
  No.

  	
  $

  



 


NOTWITHSTANDING
ANY PROVISIONS HEREOF OR IN THE ORIGINAL INDENTURE THIS BOND IS NOT ASSIGNABLE
OR TRANSFERABLE EXCEPT AS PERMITTED OR REQUIRED BY SECTION 4.04 OF THE
INDENTURE DATED AS OF AUGUST 15, 2002, BETWEEN UNION ELECTRIC COMPANY AND THE
BANK OF NEW YORK, AS TRUSTEE.


 


UNION ELECTRIC COMPANY

(Incorporated under the laws of the State of Missouri)

First Mortgage Bonds, Senior Notes Series MM


 


UNION
ELECTRIC COMPANY, a corporation organized and existing under
the laws of the State of Missouri (hereinafter called the “Company”, which term
shall include any successor corporation as defined in the Amended Indenture
referred to on the reverse hereof), for value received, hereby promises to pay
to The Bank of New York, as trustee under the Senior Note Indenture hereinafter
referred to, or registered assigns, the sum of                              Dollars,
on the 1st day of February, 2019 in any coin or currency of the
United States of America which at the time of payment is legal tender for
public and private debts, and to pay interest thereon, in like coin or
currency, at the rate of  SIX AND SEVEN
TENTHS per centum (6.70%) per annum, payable semi-annually, on February 1
and August 1 in each year until maturity, commencing February 1,
2009, and at maturity or, if the Company shall default in the payment of the
principal hereof, until the Company’s obligation with respect to the payment of
such principal shall be discharged as provided in the Amended 


 


14

















 


Indenture referred
to on the reverse hereof.  Such interest
shall be payable from the February 1 or August 1 as the case may be,
next preceding the date hereof to which interest has not been paid, unless the
date hereof is a February 1 or August 1 to which interest has been
paid, in which case from the date hereof, or unless the date hereof is prior to
the first payment of interest, in which case from June 19, 2008.  The interest so payable will be paid to the
person in whose name this Bond, or the Bond in exchange or substitution for
which this Bond shall have been issued, shall have been registered at the close
of business on the January 15 or July 15, as the case may be, next
preceding the date of payment, subject to certain exceptions set forth in the
Amended Indenture.  The principal of, premium, if any, and interest on, this
Bond are payable, in immediately available funds, at the office of the Senior
Note Trustee hereinafter referred to.


 


Under an Indenture dated
as of August 15, 2002 (the “Senior Note Indenture”) between the Company
and The Bank of New York, as trustee (the “Senior Note Trustee”), the Company
will issue, concurrently with the issuance of this Bond, an issue of notes
under the Senior Note Indenture entitled “6.70% Senior Secured Notes due 2019”
(the “Senior Notes”).  Pursuant to Article IV
of the Senior Note Indenture, this Bond is issued to the Senior Note Trustee to
secure any and all obligations of the Company under the Senior Notes and any
other series of senior notes from time to time outstanding under the Senior
Note Indenture.  Payment of principal of,
or premium, if any, or interest on, the Senior Notes shall constitute payments
on this Bond as further provided herein and in the Supplemental Indenture dated
June 1, 2008 pursuant to which this Bond has been issued (the “Supplemental
Indenture”).


 


Upon any payment of the
principal of, premium, if any, and
interest on, all or any portion of the Senior Notes, whether at maturity or
prior to maturity by redemption or otherwise or upon provision for the payment
thereof having been made in accordance with Section 5.01(a) of the
Senior Note Indenture, a principal amount of this Bond equal to the principal
amount of such Senior Notes shall, to the extent of such payment of principal,
premium, if any, and interest, be deemed paid and the obligation of the Company
thereunder to make such payment shall be discharged to such extent and, in the
case of the payment of principal (and premium, if any), such bonds shall be
surrendered to the Company for cancellation as provided in Section 4.08 of
the Senior Note Indenture.  The Trustee
(as hereinafter defined) may at any time and all times conclusively assume that
the obligation of the Company to make payments with respect to the principal of, premium, if any, and interest on, the
Senior Notes, so far as such payments at the time have become due, has been
fully satisfied and discharged pursuant to the foregoing sentence unless and
until the Trustee shall have received a written notice from the Senior Note
Trustee signed by one of its officers stating (i) that timely payment of
principal of, premium, if any, or
interest on, the Senior Notes has not been made, (ii) that the Company is
in arrears as to the payments required to be made by it to the Senior Note
Trustee pursuant to the Senior Note Indenture, and (iii) the amount of the
arrearage.


 


For
purposes of Section 4.09 of the Senior Note Indenture, this Bond shall be
deemed to be the “Related Series of Senior Note First Mortgage Bonds” in
respect of the Senior Notes.


 


This Bond shall not be
entitled to any benefit under the Amended Indenture or any indenture
supplemental thereto, or become valid or obligatory for any purpose, until The
Bank of New York, the Trustee under the Amended Indenture, or a successor
trustee thereto under the Amended Indenture, or an agent therefor, shall have signed
the form of certificate endorsed hereon.


 


15

















 


The provisions of this
Bond are continued on the reverse hereof and such continued provisions shall
for all purposes have the same effect as though fully set forth at this place.


 


IN WITNESS WHEREOF, Union
Electric Company has caused this Bond to be signed in its name by its Chairman
of the Board or President or a Vice President by manual signature or a
facsimile thereof, and its corporate seal (or a facsimile thereof) to be hereto
affixed and attested by its Secretary or an Assistant Secretary by manual
signature or a facsimile thereof.


 


16

















 


Dated,


	
   

  	
  UNION ELECTRIC
  COMPANY,

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By

  	
   

  
	
   

  	
  Vice President

  
	
   

  	
   

  
	
  [CORPORATE SEAL]

  	
   

  
	
   

  	
   

  
	
  Attest:

  	
   

  
	
   

  	
   

  	
   

  
	
  Secretary

  	
   

  
				



 


17

















 


[FORM OF TRUSTEE’S CERTIFICATE]


 


This Bond is one of the Bonds, of the series
designated therein, described in the within-mentioned Amended Indenture and
Supplemental Indenture of June 1, 2008.


 


	
   

  	
  THE BANK OF NEW YORK, as

  
	
   

  	
  TRUSTEE

  
	
   

  	
   

  
	
   

  	
  By

  	
   

  
	
   

  	
  Authorized
  Officer

  



 


[FORM OF
REVERSE OF NEW BOND]


 


This Bond is one of a
duly authorized issue of Bonds of the Company (herein called the “Bonds”), in
unlimited aggregate principal amount, of the series hereinafter specified, all
issued and to be issued under and equally secured by the Indenture of Mortgage
and Deed of Trust, dated June 15, 1937, executed by the Company to The
Bank of New York (successor trustee to Bank of America, National Association,
formerly Boatmen’s Trust Company), as trustee (herein called the “Trustee”), as
amended by indentures supplemental thereto dated May 1, 1941, April 1,
1971, February 1, 1974, July 7, 1980, February 1, 2000 and August 15,
2002, between the Company and the Trustee (said mortgage and deed of trust, as
so amended, being herein called the “Amended Indenture”), to which Amended
Indenture and all indentures supplemental thereto reference is hereby made for
a description of the properties mortgaged and pledged, the nature and extent of
the security, the rights of the bearers or registered owners of the Bonds and
of the Trustee in respect thereto, and the terms and conditions upon which the
Bonds are, and are to be, secured.  To
the extent permitted by, and as provided in, the Amended Indenture,
modifications or alterations of the Amended Indenture, or of any indenture
supplemental thereto, and of the rights and obligations of the Company and of
the holders of the Bonds may be made with the consent of the Company by an
affirmative vote of not less than 60% in amount of the Bonds entitled to vote
then outstanding, at a meeting of Bondholders called and held as provided in
the Amended Indenture, and by an affirmative vote of not less than 60% in
amount of the Bonds of any series entitled to vote then outstanding and
affected by such modification or alteration, in case one or more but less than
all of the series of Bonds then outstanding under the Amended Indenture are so
affected.  Additionally, the Company may
amend the Amended Indenture, as supplemented, by an appropriate written consent
of not less than 60% in aggregate principal amount of the Bonds outstanding
(and, if the rights of one or more, but less than all, series of Bonds then
outstanding are to be affected by action taken pursuant to such consent, then
also by consent of the holders of at least 60% in principal amount of each
series of Bonds so to be affected and outstanding hereunder) without a meeting
of such Bondholders.  No such modification
or alteration shall be made which will affect the terms of payment of the
principal of, or interest or premium on, this Bond, which are
unconditional.  The Bonds may be issued
in series, for various principal sums, may mature at different times, may bear
interest at different rates and may otherwise vary as in the Amended Indenture
provided.  This Bond is one of a series
designated as the “First Mortgage Bonds, Senior Notes Series MM” (herein
called the “Bonds of this Series”) of the Company, issued under and secured by
the Amended Indenture 


 


18

















 


and described in
the indenture (hereinafter called the “New Supplemental Indenture”) dated June 1,
2008, between the Company and the Trustee, supplemental to the Amended
Indenture.


 


The Bonds of this Series are
not entitled to the benefit of any improvement, maintenance or analogous fund.


 


This
Bond is not redeemable except on the date, in the principal amount and for the
redemption price that correspond to the redemption date for, the principal
amount to be redeemed of, and the redemption price for, the Senior Notes, and
except upon written demand of the Senior Note Trustee following the occurrence
of an event of default under the Senior Note Indenture and the acceleration of
the Senior Notes, as provided in Section 8.01 of the Senior Note
Indenture.


 


In case an event of
default, as defined in the Amended Indenture, shall occur, the principal of all
the Bonds at any such time outstanding under the Amended Indenture may be
declared or may become due and payable, upon the conditions and in the manner
and with the effect provided in the Amended Indenture.  The Amended Indenture provides that such
declaration may in certain events be waived by the holders of a majority in
principal amount of the Bonds outstanding.


 


This Bond shall not be
assignable or transferable except as permitted or required by Section 4.04
of the Senior Note Indenture.  This Bond
is exchangeable by the registered owner hereof, in person or by duly authorized
attorney, on the books of the Company to be kept for that purpose at the office
of the Company in the City of St. Louis, Missouri, upon surrender and
cancellation of this Bond and on presentation of a duly executed written
instrument of transfer, and thereupon a new Bond or Bonds of the same series,
of the same aggregate principal amount and in authorized denominations will be
issued to the transferee or transferees in exchange herefor, without payment of
any charge other than stamp taxes and other governmental charges incident
thereto; and this Bond with or without others of like series, may in like
manner be exchanged for one or more new Bonds of the same series of other
authorized denominations but of the same aggregate principal amount; all
subject to the terms and conditions set forth in the Amended Indenture.


 


No recourse shall be had
for the payment of the principal of, premium,
if any, or the interest on, this Bond, or for any claim based hereon or
on the Amended Indenture or any indenture supplemental thereto, against any
incorporator, or against any stockholder, director or officer, past, present or
future, of the Company, or of any predecessor or successor corporation, either
directly or through the Company or any such predecessor or successor
corporation, whether for amounts unpaid on stock subscriptions or by virtue of
any constitution, statute or rule of law, or by the enforcement of any
assessment or penalty or otherwise, all such liability, whether at common law,
in equity, by any constitution, statute or otherwise, of incorporators,
stockholders, directors or officers being released by every owner hereof by the
acceptance of this Bond and as part of the consideration for the issue hereof,
and being likewise released by the terms of the Amended Indenture.


 


[END OF FORM OF
REVERSE OF NEW BOND]


 


Section 4.               Until New Bonds in definitive
form are ready for delivery, the Company may execute, and upon its request in
writing the Trustee shall authenticate and deliver, in lieu thereof, New Bonds
in temporary form, as provided in Section 9 of Article II of the
Original Indenture.


 


19
















 


ARTICLE II




ISSUE OF THE NEW BONDS


 


Section 1.       The
principal amount of the New Bonds which may be authenticated and delivered
hereunder is limited to an amount equal to the principal amount of the Senior
Notes issued under the Senior Note Indenture and secured thereby and are
further subject to the limitations regarding the principal amount of Bonds
which may be issued under the Original Indenture set forth therein.


 


Section 2.       The New
Bonds in the aggregate principal amount of Four Hundred Fifty Million Dollars
($450,000,000), being the initial issue of the New Bonds, may forthwith at any
time or from time to time be executed by the Company and delivered to the
Trustee and shall be authenticated by the Trustee and delivered (either before
or after the filing or recording hereof) to or upon the order of the Company,
upon compliance by the Company with the applicable provisions of Article III
and Article XVIII of the Original Indenture.


 


Section 3.       For purposes
of Section 4.09 of the Senior Note Indenture, the New Bonds shall be
deemed to be the “Related Series of Senior Notes First Mortgage Bonds” in
respect of the Senior Notes.


 


ARTICLE III




REDEMPTION OF THE NEW
BONDS


 


Section 1.       The New Bonds are not redeemable except
on the date, in the principal amount and for the redemption price that
correspond to the redemption date for, the principal amount to be redeemed of,
and the redemption price for, the Senior Notes, and except as set forth in Section 2
of this Article III.


 


In the event that
the Company redeems any Senior Notes prior to maturity in accordance with the
provisions of the Senior Note Indenture, the Senior Note Trustee shall on the
same date deliver to the Company the New Bonds in principal amount
corresponding to the Senior Notes so redeemed, as provided in Section 4.08
of the Senior Note Indenture.  The
Company agrees to give the Senior Note Trustee notice of any such redemption of
the Senior Notes on or before the date fixed for any such redemption.  There shall be no improvement, maintenance or
analogous fund for the New Bonds.


 


Section 2.       Upon the occurrence of an Event of Default under
the Senior Note Indenture and the acceleration of the Senior Notes, the New
Bonds shall be redeemable in whole upon receipt by the Trustee of a written
demand (hereinafter called a “Redemption Demand”) from the Senior Note Trustee
stating that there has occurred under the Senior Note Indenture both an Event
of Default and a declaration of acceleration of payment of principal, accrued
interest and premium, if any, on the Senior Notes specifying the last date to
which interest on such Senior Notes has been paid (such date being hereinafter
referred to as the “Initial Interest Accrual Date”) and demanding redemption of
the New Bonds.  The Company waives any
right it may have to prior notice of such redemption under the Original
Indenture.  Upon surrender of the New
Bonds by the Senior Note Trustee to the Trustee, the New Bonds shall be
redeemed at a redemption price equal to the principal amount thereof plus
accrued interest thereon from the Initial Interest Accrual Date to the 


 


20

















 


date of the Redemption Demand; provided, however, that in the event of
a rescission or annulment of acceleration of the Senior Notes pursuant to the
last paragraph of Section 8.01(a) of the Senior Note Indenture, then
any Redemption Demand shall thereby be deemed to be rescinded by the Senior
Note Trustee although no such rescission or annulment shall extend to or affect
any subsequent default or impair any right consequent thereon.


 


ARTICLE IV




COVENANTS


 


The Company hereby
covenants, warrants and agrees;


 


Section 1.       That the
Company is lawfully seized and possessed of all of the mortgaged property
described in the granting clauses of this Supplemental Indenture; that it has
good right and lawful authority to mortgage the same as provided in this
Supplemental Indenture; and that such mortgaged property is, at the actual date
of the issue of the New Bonds, free and clear of any deed of trust, mortgage,
lien, charge or encumbrance thereon or affecting the title thereto prior to the
Original Indenture, except as set forth in the granting clauses of the Original
Indenture or this Supplemental Indenture.


 


Section 2.       That, so
long as any of the New Bonds are outstanding, whenever any officers’
certificate is required to be filed or deposited with the Trustee pursuant to Section 3(b) of
Article III of the Original Indenture upon an application for the
authentication of additional Bonds pursuant to Article III of the Original
Indenture, such officers’ certificate shall include, in addition to the matters
required to be stated therein by said Section 3(b), the statement with
respect to the net earnings of the Company available for interest after
property retirement appropriations required by Section 2 of Article V
of the Supplemental Indenture of July 1, 1956.


 


Section 3.       That, so
long as any of the New Bonds are outstanding, the Company will not apply for
the authentication and delivery of additional Bonds pursuant to Section 4
of Article III of the Original Indenture or the withdrawal of cash from
the trust estate or the reduction of the amount of cash required to be paid
into the trust estate or to satisfy the maintenance and improvement funds under
any provision of the Original Indenture or the Supplemental Indentures creating
prior series of Bonds, on the basis of the amount of $15,000,000 excluded from
net bondable value of property additions not subject to an unfunded prior lien
pursuant to Section 3 of Article V of the Supplemental Indenture of October 1,
1945, or on the basis of the amount of $7,500,000 excluded from net bondable
value of property additions not subject to an unfunded prior lien pursuant to Section 3
of Article V of the Supplemental Indenture of July 1, 1956.


 


Section 4.       That, so
long as any of the New Bonds are outstanding, the Company will not issue or
permit to be issued any prior lien bonds secured by an unfunded prior lien in
addition to the prior lien bonds secured by such unfunded prior lien at the
time of first acquisition by the Company of property subject thereto (other
than in lieu of lost, stolen or mutilated bonds or on the exchange for bonds
already outstanding of an equal principal amount of other bonds of the same issue
and the same series, if any, and of the same maturity), except upon compliance
with the provisions of Section 16 of Article IV of the Original
Indenture, nor unless the net earnings of the Company available for interest
after property retirement appropriations (determined as provided in Section 2
of Article V of the Supplemental Indenture of July 1, 1956), for any
twelve 


 


21

















 


consecutive
calendar months during the period of fifteen calendar months immediately
preceding the first day of the month in which the additional prior lien bonds
are to be issued, have been, in the aggregate, equal to not less than twice the
annual interest charges on the indebtedness specified in subparagraphs (i) and
(ii) of paragraph (1) of Section 2(a) of said Article V;
provided that, if the application for the issue of such additional prior lien
bonds is upon the basis of payment at maturity of prior lien bonds theretofore
sold or otherwise disposed of or the redemption or purchase thereof after a
date two years prior to the date of maturity, the additional requirement
imposed by this Section 4 with respect to net earnings of the Company
available for interest after property retirement appropriations shall not
apply.  Any officers’ certificate with
respect to net earnings of the Company, required to be filed with the Trustee
as a condition precedent to the issue of such additional prior lien bonds,
shall include, in addition to the matters otherwise required to be stated
therein, the matters required to be stated in an officers’ certificate pursuant
to paragraphs (1) and (2) of Section 2(a) of said Article V.


 


Section 5.       That, so
long as any of the New Bonds are outstanding, the Company will not acquire, by
purchase, merger or otherwise, any property subject to a lien or liens which
will on acquisition be an unfunded prior lien or prior liens, except upon
compliance with the provisions of Section 14 of Article IV of the
Original Indenture, nor unless the net earnings of such property available for
interest after property retirement appropriations (determined in the manner
provided in Section 2 of Article V of the Supplemental Indenture of July 1,
1956), for any twelve consecutive calendar months during the period of fifteen
calendar months immediately preceding the first day of the month in which the
first acquisition of property subject to such lien or liens occurs, have been,
in the aggregate, equal to not less than twice the amount of annual interest
charges, on all outstanding indebtedness secured by such lien or liens.  Any officers’ certificate with respect to net
earnings of such property, required to be filed with the Trustee as a condition
precedent to the acquisition of such property, shall include, in addition to
the matters otherwise required to be stated therein, the matters required to be
stated in an officers’ certificate pursuant to Section 2 of said Article V
applicable, however, only to the net earnings of such property and to the
indebtedness secured by such liens to which such property is subject.


 


ARTICLE V




THE TRUSTEE


 


The Trustee hereby
accepts the trusts hereby declared and provided, and agrees to perform the same
upon the terms and conditions in the Original Indenture and in this
Supplemental Indenture set forth, and upon the following terms and conditions:


 


The Trustee shall not be
responsible in any manner whatsoever for or in respect of the validity or
sufficiency of this Supplemental Indenture or the due execution hereof by the
Company or for or in respect of the recitals contained herein, all of which
recitals are made by the Company solely.


 


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ARTICLE VI




MISCELLANEOUS PROVISIONS.


 


Section 1.       Except as
otherwise defined herein, all terms contained in this Supplemental Indenture
shall, for all purposes thereof, have the meanings given to such terms in Article I
of the Original Indenture.


 


Section 2.       This
Supplemental Indenture may be simultaneously executed in any number of
counterparts, each of which when so executed shall be deemed to be an original;
but such counterparts shall together constitute but one and the same
instrument.


 


23

















 


IN WITNESS WHEREOF, said Union Electric Company has caused this Supplemental Indenture to
be executed on its behalf by its Chairman of the Board or President or one of
its Vice Presidents and its corporate seal to be hereto affixed and said seal
and this Supplemental Indenture to be attested by its Secretary or one of its
Assistant Secretaries; and said The Bank of New York, in evidence of its
acceptance of the trust hereby created, has caused this Supplemental Indenture
to be executed on its behalf by its President or one of its Vice Presidents,
and its corporate seal to be hereto affixed and said seal and this Supplemental
Indenture to be attested by its Secretary, or one of its Assistant Secretaries;
all as of the 1st day of June, Two thousand and eight.


 


	
  Attested:

  	
   

  	
  UNION
  ELECTRIC COMPANY, 

  
	
   

  	
   

  	
  1901 Chouteau Avenue 

  St. Louis, Missouri 63103

  
	
   

  	
   

  	
   

  
	
   /s/ G.L. Waters  

  	
   

  	
  By:

  	
  /s/ Jerre E. Birdsong   

  
	
  G.L. Waters

  	
   

  	
  Name:
  

  	
  Jerre
  E. Birdsong

  
	
  Assistant Secretary

  	
   

  	
  Title:
  

  	
  Vice
  President and Treasurer

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Signed,
  sealed and delivered by 

  	
   

  	
   

  
	
  UNION ELECTRIC COMPANY 

  	
   

  	
   

  
	
  in the presence of:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  /s/ Wayne Forbes  

  	
   

  	
   

  
	
  Wayne Forbes

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  /s/ Carol A. Head  

  	
   

  	
   

  
	
  Carol A. Head

  	
   

  	
   

  
	
  As Witnesses

  	
   

  	
   

  
						



 


24

















 


	
  Attested:

  	
   

  	
  THE
  BANK OF NEW YORK,

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   /s/ Steven
  V. Vaccarello  

  	
   

  	
  By:

  	
       /s/
  Pat Santivasci  

  
	
  Steven
  V. Vaccarello  

  	
   

  	
  Name:  Pat
  Santivasci

  
	
  Vice
  President

  	
   

  	
               Vice
  President

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Signed,
  sealed and delivered by 

  	
   

  	
   

  
	
  THE BANK OF NEW YORK 

  	
   

  	
   

  
	
  in the presence of:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   /s/ H.
  William Weber  

  	
   

  	
   

  
	
    H. William Weber

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   /s/ Michael
  Hieb  

  	
   

  	
   

  
	
    Michael Hieb

  	
   

  	
   

  
	
  As Witnesses

  	
   

  	
   

  



 


25

















 


	
  STATE OF MISSOURI,

  	
  }

  	
   

  	
   

  	
   

  
	
   

  	
  }

  	
  SS.:

  	
   

  	
   

  
	
  CITY OF ST. LOUIS,

  	
  }

  	
   

  	
   

  	
   

  



 


On this 12th
day of June, 2008, before me appeared JERRE E. BIRDSONG,
to me personally known, who, being by me duly sworn, did say that he is a Vice
President and Treasurer of UNION ELECTRIC COMPANY,
a corporation, and that the seal affixed to the foregoing instrument is the
corporate seal of said corporation, and that said instrument was signed and
sealed in behalf of said corporation by authority of its Board of Directors,
and said JERRE E. BIRDSONG acknowledged said
instrument to be the free act and deed of said corporation.


 


IN
TESTIMONY WHEREOF, I have hereto set my hand and affixed my
official seal at my office, in the City and State aforesaid, the day and year
last above written.


 


 


	
   

  	
  /s/ Donna S. Bilkey

  
	
   

  	
  Donna
  S. Bilkey – Notary Public

  
	
   

  	
  Notary
  Seal – State of Missouri

  
	
   

  	
  Jefferson
  County

  
	
   

  	
  Commission#06900096

  
	
   

  	
  My
  Commission Expires 6/13/2010

  



 


26

















 


	
  STATE OF NEW YORK,

  	
  }

  	
   

  	
   

  	
   

  
	
   

  	
  }

  	
  SS.:

  	
   

  	
   

  
	
  CITY OF NEW YORK,

  	
  }

  	
   

  	
   

  	
   

  



 


On this 11th
day of June, 2008, before me appeared  PAT SANTIVASCI, to me personally
known, who, being by me duly sworn, did say that he is a Vice President of THE BANK OF NEW YORK, a corporation, and that the seal
affixed to the foregoing instrument is the corporate seal of said corporation,
and that said instrument was signed and sealed in behalf of said corporation,
as the trustee thereunder by authority of its Board of Directors, and said  PAT SANTIVASCI,
acknowledged said instrument to be the free act and deed of said corporation as
the trustee under said instrument.


 


IN
TESTIMONY WHEREOF, I have hereto set my hand and affixed my
official seal at my office, in the City and State aforesaid, the day and year
last above written.


 


	
   

  	
  /s/ Raymond J. Keiser

  	
   

  
	
   

  	
  Raymond J. Keiser

  	
   

  
	
   

  	
  Notary Public, State of New York

  	
   

  
	
   

  	
  No KE6170210

  	
   

  
	
   

  	
  Qualified in New York County

  	
   

  
	
   

  	
  Commission Expires July 2, 2011

  	
   

  



 


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