BOARD OF TRUSTEES EXECUTIVE COMMITTEE

CARL LAMANNA, R. E. BUCHANAN CARL LAMANNA, CHAIRMAN
SOCIETY OF AMERICAN BACTERIOLOGISTS R. E. BUCHANAN

H. H. McKINNEY Bbini@iieis H. HH. MCKINNEY
ee ee eee ee GHULTZ AMERICAN TYPE CULTURE COLLECTION

NOE.
AMERICAN ASSOCIATION OF 2029 M STREET, N. W. REE OR iss
PATHOLOGISTS AND BACTERIOLOGISTS WASHINGTON 6, D. C. .
CE, R. P. HALL
AMERICAN SOCIETY OF ZOOLOGISTS ASSISTANT CURATOR
R. W. DAVIDSON R. LLOYD PHILLIPS

MYCOLOGICAL SOCIETY OF AMERICA
ISABELLA S. BOULDIN, BACTERIOLOGIST

N. R. SMITH RUTH D. DAVIS, BACTERIOLOGIST
AMERICAN INSTITUTE OF BIOLOGICAL SCIENCES

R. D. COGHILL, G. W. IRVING, JR.
NATIONAL RESEARCH COUNCIL

SECRETARY-MANAGER
KATHERINE ALVORD

June 10, 1953

Dr. Joshua Lederberg
Depertment of Genetics

The University of Wisconsin
Medison 6, Wisconsin

Dear Doctor Lederberg:

Thank you for providing a clue to strain 550-460 of E. coli,
It proved to be one of Dr, Roepke's mutants, a uracil-requiring
strain, not mentioned as yet in literature,

We have not done as much with the silica gel method of preserving
cultures as I had hoped, but have by no means lost interest in it, Onr
one staff member whose duties allowed him any tine for research re-
fused to even try this method in comparison with other preservation
techniques, Others of us have set up a few tests on three species of
bacteria and six molds, All have survived for three months or more
but we have no quantitative data on survival,

We have submitted an application to the National Science Foundation
for a grant that would enable us to take up this study comprehensively,
T am especially interested in the possibility of using this method to
preserve becteriophazses, In a paper soon to appear in Applied Microbiology,
C. C. Prouty of Washington State College, reports the use of dried filter
paper strips in preserving a phage of Streptococeus lactis for five or
six years without vacuum seal or temperature control. This process re=
quires artificial drying of the strips after soaking in the phage suspension,
Your method would obviate such drying, I am trying to persuade him to
try the silica gel method on his phage,

With cordial rezards,
Sincerely,

Frcenvas Aa. ee,

Freeman A. Weiss
Curator

FAW/ap