April. 15, 1949.
Dear Jacques,

Thanks very mach for the Bacillus megatherium cultures which were
received in good condition. I am sorry that you did not have the Lisbonne-
Carrisre strain, but I have sent out further inquiries for it.

_I hope that you did not propose very seriously that the lysogenic
phaga is a spermitozcoid. I have been afraid to talk about it to sons
bacteriologists for fear of raising confusion with recombination, The
two processes are juite independant, and recombination occurs quite well
with non-lysogenic cultures.

I reguet very mich that I have very small supplies of the galactosides,
and would have to curtail inportant experiments if I gave up what I had.
However, I hope to have the opportunity to send you cells of K-12 or
other strains (notably Lac,-) which have been grown on galactosides for

these experiments.A amall quantity of such dried cella would make sufficient
extract for your needs; to break up the galactoaide supply would make it
difficult to handle the snall quantities of adapted cells separately obtained.
The galectosides ara not too difficult to make by a trained chenist, and

I wonder whether you could not make such arrangements. The standard methods
fathe literature aro juite suitable,

Ags you de have Lactcbicnate, I would suggest that it aight be worthwhile
to check on my statement that this compound will evoke galactosidase in
Kel2 ulthough I have been ables to find no evidenca for its combination with
the anzvne.

I hope you will pardon my hasty statements, some of shich will have to
we revoked. It haa been my feeling that since we were aorking along parallel
lines, and could check on each other's results, that wa could do each other
& great service by checking and verifying even premitare conclusions, not
to speak of discussing theg.

Lately I have been looking at the galactosidases produced by some suppressor
genotypes, but have found no reiaarkuble deviations from the "standard" enzyme.
This again alight support the notion that the locus operandi of the gene is
not usually on the specificity of the enzyme but on different componente
of the adaptive process.

Yours sincerely,

Joshua Lederberg