ROLE OF AMINO ACIDS IN POSTEXPONENTIAL GROWTH.

Toennies, Gerrit (Temple University, and The Institute for Cancer Research, Philadelphia, Pa.). Role of amino acids in postexponential growth. J. Bacteriol. 90:438-442. 1965.-It was shown earlier that depletion of different essential amino acids from the medium of growing Streptococcus faecalis leads to the formation of cell types of different compositions in terms of cytoplasm, wall, and membrane. The findings presented now indicate that these postexponential effects can be induced by very low concentrations of incomplete amino acid complements, that cystine and methionine have major and separate effects, and that these effects may be modulated differentially by the presence of different combinations of other amino acids.