SUMMARY: dl-Norvaline inhibits growth of wild-type Bacillus subtilis. A number of mutants resistant to growth inhibition by this analogue were isolated and studied. Cross-feeding experiments and paper chromatography of culture supernatants indicated that the mutants excreted leucine and possibly valine and glutamate. Enzymic analysis indicated that the mutants were derepressed for acetohydroxy-acid synthetase and α-isopropylmalate synthetase; however, no derepression of threonine deaminase, dihydroxyacid dehydrase or transaminase B was observed.
BauerleR. H.,
FreundlichM.,
StörmerF. C.,
UmbargerH. E.1964; Control of isoleucine, valine and leucine biosynthesis. II. Endproduct inhibition by valine of acetohydroxyacid synthetase in Salmonella typhimurium. Biochimica et biophysica acta 92:142–149
CalvoJ. M.,
FreundlichM.,
UmbargerH. E.1969; Regulation of branched-chain amino acid biosynthesis in Salmonella typhimurium: isolation of regulatory mutants. Journal of Bacteriology 97:1272–1282
HatfieldG. W.,
UmbargerH. E.1971; l-Threonine deaminase, biosynthetic (Bacillus subtilis). In Methods in Enzymology17B561–566TaborH.,
TaborC. W.
Edited by New York and London:: Academic Press;
KiritaniK.,
WagnerR. P.1970; α,β-Dihydroxyacid dehydrase (Neurospora crassa and spinach). In Methods in Enzymology17A755–764TaborH.,
TaborC. W.
Edited by New York and London:: Academic Press;
LowryO. H.,
RosebroughN. J.,
FarrA. L.,
RandallR. J.1951; Protein measurement with the Folin phenol reagent. Journal of Biological Chemistry 193:265–275
SzentirmaiA.,
SzentirmaiM.,
UmbargerH. E.1968; Isoleucine and valine metabolism of Escherichia coli. XV. Biochemical properties of mutants resistant to thiaisoleucine. Journal of Bacteriology 95:1672–1679