CALIFORNIA INSTITUTE OF TECHNOLOGY

         PASADENA, CALIFORNIA

DIVISIOh- OF BIOLOGY

June 11, 1956

Dr. Joshua Lederbsrg
Genetics Dept.
University of Wsconsin
Madison 6

Dear Josh,

   I had forgotten that Rowley tested our temperature mutants. I did keep them
around for a couple of years, thinking somebody might want to use them, but they finally
got thrown out.  Sorry I can't help you--you should have written 3 years ago!

   Are you, by any chance, getting one of the free trips to Japan?  If so, maybe
we could travel part of the way poeether and have a seminar on gene-enzyme problems.

   I don't&ink you are quite right in saying that the older Neurospora papers
contain wild statments about genes making enzymes.  In glancing through the papers
you cited, I was pleased to find that they are carefully worded and say no more than
was intended.  You find phrases such as "genes control enzyme production", or "determine
enzyme specificitytl or "act somehow as a template", which may be vague, but certainly
not idiotic.  I think that people have read into these statements more than was intended.
Perhaps we should have been explicit inx spelling out what was not meant, but one likes
to assume a common semantic background when addressing fellow s=ntists, and this may
not be justified.  I criticize the older papers for not having made clear that when
enzyme specificity was being talked about it wa s not just substrate specificity, as
some oeonle now seem to think, but all aspects of enzyme specificity. I also criticize
them for having placed the "one enzyme per gene" and the "one gene per enzyme" hypotheses
on an equal footing.

   With regard to your !&I.-Lp example, if you will tell me ahat the chemical basis of
virus resistance ie, I yill undertake to exolain the pleiotropism. For all I knov,
resistsnce to lambda may be as complicated as the ability to compose a sonata.  Your
case is no more surprising than the threonine-methionine pleiotropism was when we first
discovered it; they only become simple when you work them out.

   Anyway, I am glad that we agree as much as we do on these matters. Personally,
I believe that,considered as a purely empirical finding, the one-to-one relation is
the most important thing that has been found out about mutations in the last 20 years.
It seems odd that other int,elPigent people don't always agree with me about this.

Norman Horowitz


ADVAIGES IN MICROBIAL PEULOLOC-Y

B. H. Horowitz

California Institute of Technology, Pasadena

   I was etartled to read in the September 5. 1952 issue of Science, under

the heading %eactions of the Porpoise to Ultrasonic Frequencies" by W. E31. Rel-

logg and X. Kohler, the following: "Projection of these frequencies into the

water was accomplished by a USRL transducer...."  On looking up transducer in

Webster's lpew International Dictionary I found this definition: "A device ac-

tivated by power from one system and supplying power in the same or any other

form to a second system.  For example, a telephone receiver...."
  Out of idle curiosity I thumbed through the dictionary (a 1936 edition)

looking for others of the new words of microbial genetics. I found two more;

namely, prototrophic and srntrophic.  The latter is defined in a way which is

consonent with its current usage in microbial genetics and need concern us no

further .  Prototrophic, however, is defined as follows: "Deriving nutriment, or

the energy of anabolism, from uncombined elements, as the nitrogen-fixing bacteria

and sulfur bacteria."  There is no sign that this usage is obsolete.  In fact,

it can be found in recent bacteriology textbooks, such as Tanner 5% Tanner, and

Frobi sher .  (J'robisher incorrectly makes it synonymous with autotrophic).

   The::e discoveries undoubtedly prove the utility of articles on porpoise

Phssioloey, even for microbial geneticists.  In addition, they raise questions

concerning the status of the words transducer and prototronhic.  On the principle

that one -should never court confusion when it can be easily avoided, it would

seem to follow that these wards should no longer be used with the deaatafions

they have recently acquired in microbial genetics.

  These findings also bring up the question of how much philological reseerch

may be expected of an author who desires to launch a neologfsm, and beyond this

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2.

the more -mental problem of deciding in each instance whether or not the

coining of a neologism is justified.  In connection with the latter problem I

should like to suggest that one must avoid the temptation to fabricate neologisms

merely as a matter of convenience.  Convenience by itself does not proride suf-

ficient justificatioc for a neologism.  There must also be a need for the US

term.  Otherwise we shall soon have a jargon which is intelligible only to a

prfestly class of ititiates and which hinders rather than facilitates communication.