HDTenEightyP/NetNews huggingface dataset:
From: zxmkr08@studserv.zdv.uni-tuebingen.de (Cornelius Krasel)
Subject: Glyoxal electrophoresis for RNA
Organization: Comp. Center (ZDV) U of Tuebingen, FRG
Date: Mon, 23 Nov 1992 08:15:42 GMT

Hello netters,
I have a question concerning glyoxal electrophoresis of RNA.
According to Maniatis, the gels are poured and run in 10 mM sodium
phosphate. IMHO this is rather inconvenient because the capacity
of this buffer is rather weak; you must either attach a pump to
the electrophoresis apparatus or manually mix the buffer reservoirs
every half an hour.
What is the reason that you have to run the gels in such a weak
buffer? Why can one not use e.g. 100 mM sodium phosphate? (We
did this once accidentally, and it worked quite fine, but are
there any theoretical reasons against it?).
Thanks in advance, Cornelius.
--
/* Cornelius Krasel, Department of Physiological Chemistry, U Tuebingen    */ 
/* email: krasel@studserv.zdv.uni-tuebingen.de (Internet)   HAS CHANGED!!  */
/*        NO WIN/X400 MAIL POSSIBLE AT THE MOMENT!                         */
/* "People are DNA's way of making more DNA." (anonymous)                  */
From: wetsel_r@wums.wustl.edu
Newsgroups: bionet.molbio.methds-reagnts
Subject: Immunoprecipitation question
Date: 23 NOV 92 16:01:38 GMT
Organization: MIT PLASMA FUSION CENTER
NNTP-Posting-Host: msnews.wustl.edu

Greetings Netters:

We do immunoprecipitations all the time in our lab, both biosynthetically
labeled and surface labeled, with polyclonal and monoclonal antiobodies,
respectively. 

My question is:  Does anyone have a protocol for doing immunoprecipitations
from biosynthetically labeled cells with monoclonals? 

Our polyclonal protocol works great but uses 0.5 Triton X100, 0.5% DOC, and
1% SDS but as one might expect this wash solution doesn't cut it for
monoclonals, in fact, the SDS blows them away leaving me with a blank gel! 
Decreasing the SDS, so far, only increases the background.  Has anyone
tried various salt combinations? 

Any suggestions?

Thanks in advance,

David L. Haviland
haviland@kids.wustl.edu
From: Carlos.Faerman@BRI.NRC.CA (Carlos Faerman)
Newsgroups: bionet.molbio.methds-reagnts
Subject: (none)
Date: 16 Nov 92 17:42:13 GMT
Distribution: bionet

I would like to pose the following question:
Is there any review article/Book/or Table that summarizes kcat, Km for
each enzyme?
I find it very tedious to look for each enzyme on an individual basis.
Please let me know
Carlos Faerman
 carlos@bri.nrc.ca
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: Live Bgal detection
From: robison1@husc10.harvard.edu (Keith Robison)
Date: 19 Nov 92 15:50:54 GMT


>Hey all! I wonder if anyone can recommend a way of detecting 
>B-galactosidase activity in living eukaryotic tissue or cells
>without having to fix them? Well, if you can't think of one, how
>about a different reporter gene that can be detected in live
>tissue? 

Look in Molecular Bioprobes' catalog -- they have a number of
substrates for a number of enzymes (including lacZ) which can
be used in living tissue.  Luciferases are another option --
either the firefly or bacterial ones (which use different
substrates).



Keith Robison
Harvard University
Department of Cellular & Developmental Biology
Department of Genetics / HHMI

robison@biosun.harvard.edu
From: 76467.702@CompuServe.COM (Alan Gerstein)
Newsgroups: bionet.molbio.methds-reagnts
Subject: RNA from seeds
Date: 18 Nov 92 18:05:31 GMT
Distribution: bionet

he is trying to isolate mRNA from tobacco seeds. he has already tried two
classes of methods: guanidinium and phenol. basically what happens is that
everything turns an ugly kind of brown and is very sticky.
to circumvent this, he has added vitamin C and triton: total RNA looks 
better then.
but he is unable to isolate mRNA with either dynabeads or oligo dT 
cellulose...
both these matrices are attacked by his total RNA mix and partly
destroyed (this could be a pH effect: the Fe++ may dissolve from the
magnetobeads at low pH).
------
Check out Analytical Biochemistry, 162:569-574 (1987).  Not plants, but 
authors found way to obviate problem from carbohydrate rich tissue.

Alan
Pharmacia
From: byrne@soma.UMDNJ.EDU (Bruce Byrne)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: reference manager
Date: 18 Nov 92 13:22:28 GMT
Distribution: bionet

gessler@convex.HRZ.Uni-Marburg.DE (Gessler Manfred Dr.) writes:


>Does anybody know about the advantages/disadvantages of the several reference
>managing programs for DOS systems like Reference Manager, Ref-11, Payrus etc.
>What are the disk space requirements for the growing databases? 
>Any recommendations or comments are welcome!

I'm very happy with Reference Manager, having used two different 
versions over the last three years.  Version 5.03 (recent but latest??)
requires about 1.8 meg on disk.  My 1,900+ references, about half of 
which contain notes or abstracts, require another 1.9 meg.  I have no
experience with the other packages.

Bruce Byrne
From: camdna@ubvmsb.cc.buffalo.edu (Darren Natale)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: Live Bgal detection
Date: 19 Nov 92 15:33:00 GMT
Organization: University at Buffalo
News-Software: VAX/VMS VNEWS 1.41

In article <1992Nov19.041136.18053@news.columbia.edu>, rss19@cunixa.cc.columbia.edu (Richard S Sucgang) writes...
> 
>Hey all! I wonder if anyone can recommend a way of detecting 
>B-galactosidase activity in living eukaryotic tissue or cells
>without having to fix them? Well, if you can't think of one, how
>about a different reporter gene that can be detected in live
>tissue? For that matter, is there a gene that can be selected
>*against* in non-dividing cells, that is, cells carrying the
>gene can be actively killed?
> 
>thanks for the help!
> 
>e-mail if you'd like, and i'll summarize
> 
>-rich
>rs54@cunixf.cc.columbia.edu
>"Working with Dicty? Have you tried the Franke database yet?"

Please clarify--what kind of eukaryotic cells are you using?
Newsgroups: bionet.molbio.methds-reagnts
From: broe@aardvark.ucs.uoknor.edu (Bruce Roe)
Subject: Re: Multi-Pol DNA Sequencing System
Originator: usenet@midway.ecn.uoknor.edu
Date: Fri, 20 Nov 1992 12:58:00 GMT
News-Software: VAX/VMS VNEWS 1.41    
Organization: University of Oklahoma - University Computing Services

In article <1992Nov19.103922.1@kean.ucs.mun.ca>, mulligan@kean.ucs.mun.ca (Martin E. Mulligan) writes...
>Has anyone ever used the Multi-Pol DNA Sequencing System sold by
>Clontech?  Can you recommend it or otherwise?  In particular, how
>does it compare with Sequenase?  By the time we pay for extra dry ice
>and shipping, Sequenase kits become prohibitively expensive here - I'd
>like to find a reliable alternative and would be interested in other
>labs' experiences with other sequencing systems.
> 
>Thanks,
> 
>Martin E. Mulligan
>Dept. of Biochemistry, Memorial University of Newfoundland
> 
>email: mulligan@kean.ucs.mun.ca
> 
Hi,
        We've never tried the Multi-Pol DNA Sequencing System but it
originally was introduced because the two-step reaction used in the
Tabor-Richardson Sequenase paper gave very faint data in the regions
close to the priming site.  I think that problem now has been eliminated
in the present Sequenase protocols.
        As for saving money,  buy one kit, mainly to obtain an "tried and
true" control as well as a copy of the protocol, AND THEN buy the "kit
components" separately and make your own "kit".  This is a very inexpensive
approach if, for example, you will be doing alot of sequencing and take
the time to investigate using a "home made" kit based on the commercial
"kit".  If it saves you money, then make your own kit.
        I'm not a big believer in "kits" but do feel they have their place
in the laboratory, expecially when a new procedure is being tried.
        I'm a little hesitant to send this message as I don't think we
need another "kit-war" but this gives me the opportunity to put a plug
in for the AUTOSEQS@NET.BIO.NET.

  * * * * * * * * * * * *  AUTOSEQS@NET.BIO.NET * * * * * * * * * * * *
  * * * * * a forum which deals with automated DNA sequencing.* * * * *
  * Subscription requests for AUTOSEQS@NET.BIO.NET regardless of your *
  * geographical location should be directed to BIOSCI@NET.BIO.NET as *
  * long as this list remains in its current status.  All messages to *
  * the list should be sent only to autoseqs@net.bio.net.             *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Cheers........bruce
  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 \  Bruce A. Roe               Professor of Chemistry and Biochemistry /
 /  University of Oklahoma     INTERNET: BROE@aardvark.ucs.uoknor.edu  \
  - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  - - -
From: djt2@po.CWRU.Edu (Dennis J. Templeton)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: site-directed mutagenesis
Date: 17 Nov 1992 15:11:04 GMT
Organization: Case Western Reserve University, Cleveland, OH (USA)
Reply-To: djt2@po.CWRU.Edu (Dennis J. Templeton)
NNTP-Posting-Host: thor.ins.cwru.edu


In a previous article, wsun@jeeves.ucsd.edu (Fiberman) says:

>Dear netters,
>
>I am trying to do site-directed mutagenesis using the Bio-rad
>kit.  I am using CJ236 cells and my clone in the Bluescript
>plasmid to make SS DNA with VCM13 helper phage.  Following the
>protocol, I do a negative control where I add everything except
>the mutagenic primer.  However, when I transform XL1-blue cells
>with this negative control DNA, I get colonies on the plate.  In
>addition, when I screened the colonies from my positive plate, I
>don't get any mutants, only wild type.  Can anyone out there
>have had this problem and could offer some
>explanation/solutions?
>
>-fm
> 
>

I think the biggest variable in this reaction (we use the same reagents from
BioRad, since the enzymes in the kit refill are cheaper than by themselves) 
is in the purity of the template SS DNA.  Any contaminating oligonucleotides 
from the prep will prime "randomly" and will result in wild-type background.

Try a couple extra steps of purifying the SS DNA away from any small 
nucleic acids.

Also, double (or triple) check the sequence and orientation of your 
mutagenic oligo. While troubleshooting effots from *other peoples labs* ;=)
we've encountered all too many mistakes of that kind.

good luck,


dennis
From: dahl@sun1.ruf.uni-freiburg.de (Michael Dahl)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: Protein phos assays, TCA and dot blot manifolds
Date: 18 Nov 92 14:16:45 GMT
Organization: Rechenzentrum der Universitaet Freiburg, Deutschland

pcovello@ac.dal.ca writes:

>Speaking of protein phosphorylation assays, I have a 
>question along similar lines. I am looking for a very
>rapid method for TCA precipitation/scintillation 
>counting of nucleic acids. I have read that a vacuum
>manifold can be useful for washing filters and I 
>notice that the "Minifold" on p. 20 of the 1992
>Schleicher and Schuell catalogue is recommended
>for this purpose. Does anyone have any experience
>using a vacuum manifold for this purpose. Can anyone
>recommend a protocol for its use?

>Pat Covello
>Dept. Biochemistry
>Dalhousie University
>Halifax, NS
>Canada

Dear Pat,

I do not have the catalogue from Schleicher and Schuell-anyway, may be
I can help you. I used a very rapid method for the DegS phosphorylation
of Bacillus sublitis for the determination of its Km for ATP. The Method is described in our paper: Dahl et al. 1991, J.Bacteriol. p 2539-2547. You need
nitrocellulose filters (0.05 micrometers of pore size). 
The method as described is really rapid and simple to handle.
If you have more questions feel free ad contact me.
Michael
dahl@sun1.ruf.uni-freiburg.de
-- 

Michael Dahl
Universitaet Freiburg (Biologie III)
Schaenzlestrasse 1
From: bsh@MED.PITT.EDU (Basavaraju Shankarappa)
Newsgroups: bionet.molbio.methds-reagnts
Subject: kits and kits and kits and mutagenesis
Date: 15 Nov 92 18:10:09 GMT
Distribution: bionet

>From: wsun@jeeves.ucsd.edu (Fiberman)
>I am trying to do site-directed mutagenesis using the Bio-rad
<kit.  I am using CJ236 cells and my clone in the Bluescript
>plasmid to make SS DNA with VCM13 helper phage.  Following the
>protocol, I do a negative control where I add everything except
> 	the mutagenic primer.  However, when I transform XL1-blue cells
>with this negative control DNA, I get colonies on the plate.  In
>addition, when I screened the colonies from my positive plate, I
>don't get any mutants, only wild type.  Can anyone out there
>have had this problem and could offer some
>explanation/solutions?

>-fm

One suggestion regarding the above type of questions.  I think it will
be best for both people who read it and for those who post it, if you 
can please explain the method used in any of the above kits.  As you
all know many companies make more than one kind of kit and there are 
so many kits out there it is not possible for anyone to keep track of  
all types of kits.  Although it is very easy for us to think that the
procedure or the kit we are using is the best in the whole wide world
it is highly likely that many people never heard of it.  Also, we may
not have the time or patience to go the company catalog and see what 
the procedure involves.  If you explain the method, may be somebody
who used the method but not the kit will be able to help you.
 
	I think it is this presumption in kit users that infuriate the 
people of Jim Graham types.  I can very easily understand their 
frustration at having to work with pro-kit-robotic people.  As a 
cautious supportor of kits, this is just my opinion.  We need both
Jim Graham and Steve Mosley.  
Raj Shankarappa
bsh@med.pitt.edu
From: bsh@MED.PITT.EDU (Basavaraju Shankarappa)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: dye removal from ABI terminator reactions.
Date: 23 Nov 92 20:44:08 GMT
Distribution: bionet

> and add about 25 ul volume of zirconium glass beads.  Then I pour sephadex
                                ^^^^^^^^^
> G-50 in 0.3M NaAc (5g in 60 ml) to the top of the tube.  Stick the small
> eppendorf inside a 2 ml tube and spin at about 500 rpm for couple of minutes.
> Now the tube is transferred to a new 1.5 ml tube and the sample is added on
> top.  Now I spin at about 1500 rpm for couple of minutes.  
> The eluate is precipitated by atleast 3 volumes of isopropanol washed with
> 70% etoh and resuspended for loading.

>Thanks for the method.  One question: why _zirconium_ glass beads?  
>Wouldn't regular glass work as well?  And what size beads do you use?

>WMELCHIOR@NTET.NCTR.FDA.GOV                  ||       from Grooks, Piet Hein

I guess any bead that settles at the bottom should work.  I was under the 
impression that zirconium might bind less DNA as opposed to the regular
glass since glass is well known for its DNA binding properties.  
Now I have learnt that zirconium is not much different from glass and 
when used in the presence of salt concentrations like 0.3 M NaAc, DNA 
should not be binding through ionic interactions.  Bottom line any matrix
that can withold sephadex should be fine.

I used 0.1-0.15 mm size beads.  The catalog number I supplied was for the 
sizes I used.
I will be very interested to know how it works for those trying it.
Raj Shankarappa
bsh@med.pitt.edu
From: horton@molbio.cbs.umn.edu (Robert Horton)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: Help needed: genomic DNA isolation
Date: 18 Nov 92 02:58:49 GMT
Organization: University of Minnesota
X-Newsreader: Tin 1.1 PL5


        I had a similar problem working with mouse genomic DNA. The trick
was to add the ethanol gradually, without using any more than was necessary
to precipitate the DNA. With high concentrations of high molecular weight
DNA, this may amount to only one volume of EtOH. Presumably, more EtOH
removes more water from the DNA, and makes it more difficult to re-dissolve
after precipitation. It still may take some time to dissolve since you
have to agitate it very carefully to avoid shearing, but by using the
minimum amount of EtOH, it should go in a lot faster.

--
Bob Horton            /\ "Crash programs fail because of the theory that
U. of Minnesota, CBS  || with nine women pregnant you get a baby a month" 
1479 Gortner Ave.    /||\   -Werner von Braun.  Disclaimer:"Bob who?"
St. Paul, MN 55108    ^^   horton@molbio.cbs.umn.edu/(612) 624-3790
From: sl14z@cc.usu.edu
Newsgroups: bionet.molbio.methds-reagnts
Subject: PCR
Date: 23 Nov 92 18:41:08 MDT
Organization: Utah State University

If anyone could possibly help with information pertaining to PCRing a
2000bp sequence, please do so by sending a Vax mail message to this 
address.  I have been attempting to amplify an IGS region from a 
Laccaria bicolor dik. collector Kropp using sequenced primers at
approx. 15 b (depending on the primer).  I have used low annealing
temperatures but have only once achieved a fragmented amplified area.
If anyone has any tips or advice please respond.
					
						Thanks,
						Steve Albee
						Utah State University
Newsgroups: bionet.molbio.methds-reagnts
From: jgraham@bronze.ucs.indiana.edu (the End)
Subject: Origin of MV1190 ????
Organization: Indiana University
Date: Mon, 23 Nov 1992 17:19:41 GMT

Bioneters,

Does anyone have the correct reference for the E. coli strain MV1190 ?
The only printed material I have ever seen that describes it is the 1990
IBI catalouge (Eastman Kodak). It is well described there as a recAD mutant
of JM101 with the mutation (srl-recA)306::Tn10. It also is described as 
having the F plasmid  F'/proAB lac IQ lacZdM13 traD36.  Is the designation
lacZdM13 a typo (lacZdM15) ? If not is anyone framiliar with a M13 lac 
deletion ?

Any references, stories, and anecdotes on this strain, and comparisons with
similar E. coli strain in terms of effiency in standard procedures would 
be greatly appreciated.

Thanks much,

Jim
J. Graham
Biology/Chemistry Depts.
From: LEES@SASK.USASK.CA
Newsgroups: bionet.molbio.methds-reagnts
Subject: Looking for small vector
Date: 20 Nov 92 21:19:59 GMT
Distribution: bionet

Hi, Bionetters!

If does anyone have information about small vector which has 
both ampicillin and kanamycin markers with less than 3Kb,
please let me know.


Thanks in advance.



Sun


e-mail: lees@sask.usask.ca
Newsgroups: bionet.molbio.methds-reagnts
Subject: Result from "Primer" programme
From: biosmd@luxor.latrobe.edu.au (Sean Davidson)
Date: Sun, 22 Nov 1992 03:59:31 GMT
Organization: La Trobe University
Originator: biosmd@luxor.latrobe.edu.au


I have been using the "Primer" programme on the published sequence of a mouse
gene (HSP70.1) and it reports homology in the 3' non-transcribed region, with
the mouse repetitve element B2.
My question is, could this explain why my attempts at using a probe which
is derived from the 3' region of this gene, has failed so far in Southern
blots - all I get is hybridization to apparently all DNA, even when washed
at 65 degrees in 0.1xSSC.
Does anyone know HOW homolgous the sequence has to be before Primer reports
it ?

Any comments appreciated,
Sean
From: hrvoje.fulgosi@olimp.irb.ac.mail.yu (Hrvoje Fulgosi)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: help needed: genomic DNA isolation
Date: 18 Nov 92 14:52:48 GMT
Distribution: bionet
Importance: High
Content-Identifier: 62
Original-To: methods@uk.ac.daresbury
Conversion: Prohibited
Priority: Urgent

Since I've read this: 

>I've been trying to isolate plant genomic DNA from leaf for making a

>genomic library. The procedure I used is quite straight forward: grind

>leaf, extract, collect nuclei by centrifugation, then lyse by 2% CTAB,

>phenol/chloroform extract twice, ethanol precipitate DNA, redissolve

>in 20 mM Tris pH8, 10 mM EDTA overnight at 4C, followed by another

>phenol/chloroform/ethanol ppt. and redissolve in TE.

>............the biggest problem with this method is the difficulty in

>redissolving DNA after ethanol ppt.

and this:

>> I had a similar problem working with mouse genomic DNA. The trick

>>was to add the ethanol gradually, without using any more than was necessary

>>to precipitate the DNA.

>> ....... Presumably, more EtOH removes more water from the DNA, and 

>>makes it more difficult to re-dissolve after precipitation.

and this:

>>>2:0.6x ice-cold isopropanol; pellet in clinical centrifuge.



I've decided to post this to all:

For precipitation try using 1/10 v/v of 3M potassium acetat and 1 v/v of

isopropanol. Precipitate will form on room temp. Pellet by low speed cent.

DNA should dissolve well.



Good luck,

           Harvey



Hrvoje Fulgosi, Ruder Boskovic Institute, Zagreb, Croatia.
From: ca566@cleveland.Freenet.Edu (Michael Holloway)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: sequencing from 300-500 bp
Date: 23 Nov 92 18:13:14 GMT
Reply-To: ca566@cleveland.Freenet.Edu (Michael Holloway)
Organization: Case Western Reserve University, Cleveland, OH (USA)
NNTP-Posting-Host: hela.ins.cwru.edu


In a previous article, mm6y+@andrew.cmu.edu ("Morris F. Manolson") says:

>Dear Netters,  I am sure someone must have asked this before but......
>
>I am trying to sequence off of one reaction 300 to 500 bps using the 
>standard IBI or BRL 44 cm glates.  Without having to resort to ultra-long
>plates (of which I don't have), does anyone have any suggesting on how to
>improve the resolution of the bands in the 300 to 500 bp region.  My reactions
>are fine and I can see bands up to 600 bp from the primer, I just can't
>resolve them well enough to read.  I am using 6% acrylamide wedge gels and run
>them for 24 hours at 900 Volts, this gives me nice sequence on average
>up to 350 bp,  on a great gel I can get 400.  I remember some company trying
>to sell an alternative matrix to acrylamide, (of course I don't remember
>who or where) which they claimed improved resolution, does anyone
>out there know what I am talking about?  Thanks in advance, Morrie 
>

Based on my experience (and I think the other replies to your questions
bear me out in this) the best advice I can give you is not to try.  Bite
the bullet, make or contract out for an oligo and prime from within your
last bit of sequence.  Even if you do manage to get that last little bit of
sequence out of it the quality will be extremely low.  I've been there and
I can honestly say that I wish I hadn't gone.

Mike
-- 
E-mail: mhollowa@ccmail.sunysb.edu (mail to freenet is forwarded)
phone:  (516)444-3612
From: BMA14432@VAX1.UTULSA.EDU
Newsgroups: bionet.molbio.methds-reagnts
Subject: Staining cells with lectins
Date: 17 Nov 92 17:08:19 GMT
Distribution: bionet


Dear Netters,
 	Does anyone out there have experience staining adherant
cells with lectins?
I want to  stain a CHO derivative called CHOP cell with PHA-L and 
would like to get information concerning the correct concentration to
optimize for fluoresence.(The PHA-L is FITC conjugated) Yes I could
do the experiment but it is VERY expensive for a lab our size.
Thanks in advance.
Mark Brudnak
University of Tulsa
Internet: BMA14432@VAX1.UTULSA.EDU
From: skspoidn@reading.ac.uk
Newsgroups: bionet.molbio.methds-reagnts
Subject: PUC119
Date: 21 Nov 92 13:37:48 GMT
Distribution: bionet
Original-To: methods@uk.ac.daresbury

Puc119 is mapped and reasonably well described on page 
1.14 of the Bible (Sambrook, Fritsch and Maniatis)

Mike Poidinger
Dept of Microbiology
University of Reading
From: jgraham@bronze.ucs.indiana.edu (the End)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Re: PCR Mutagenesis
Date: 16 Nov 92 17:29:22 GMT
Organization: Indiana University


Brian,

Ahhh. Now we know what 45 cycles can do. Sounds like a great mutagenesis
procedure. Just think what multiple rounds will do.

PS. I'm still waiting for info on the influence of Mn++ ions.

Jim
From: BMA14432@VAX1.UTULSA.EDU
Newsgroups: bionet.molbio.methds-reagnts
Subject: TEST
Date: 17 Nov 92 21:26:15 GMT
Distribution: bionet

TEST
Newsgroups: bionet.molbio.methds-reagnts