Masahiko Kisumi

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Proline-producing strains of Serratia marcescens were more osmotolerant than wild-type strains. Growth inhibition by proline analogs was significantly enhanced by increasing the osmotic stress of the medium. Mutants resistant to azetidine-2-carboxylate were derived from a proline-producing strain, SP126, under a high osmotic condition. One of the mutants,(More)
2-Methylhistidine (2MH) and 1,2,4-triazole-3-alanine (TRA) inhibited the growth of Serratia marcescens. These inhibitory effects were counteracted by L-histidine. Enzymatic studies showed that 2MH acts as a false feedback inhibitor and TRA acts as both a false feedback inhibitor and a repressor. Mutants resistant to each analog were isolated from a(More)
L-Arginine biosynthesis in Serratia marcescens Sr41 was found to be controlled by (a) feedback inhibition of N-acetylglutamate synthetase and (b) repression of some L-arginine biosynthetic enzymes, and an L-arginine-degrading system was found to exist. Accordingly, an L-arginine-producing mutant (aru argR argA) of S. marcescens Sr41 was constructed as(More)
l-Arginine hydroxamate inhibited the growth of various bacteria, and the inhibition was readily reversed by arginine. l-Arginine hydroxamate (10(-3)m) completely inhibited the growth of Bacillus subtilis. This inhibitory effect was prevented by 2.5 x 10(-4)ml-arginine, which was the most effective of all the natural amino acids in reversing the inhibition.(More)
Several alpha-aminobutyric acid-resistant (Abu-r) mutants of Serratia marcescens were found to be superior to the parent strain in converting d-threonine to l-isoleucine. One of them accumulated 1.5 times more l-isoleucine that the parent strain. The level of acetohydroxy acid (AHA) synthetase in this mutant increased twofold above that of the parent(More)
A decrease in histidine productivity was observed during subculture of a histidine-producing strain of Serratia marcescens. The decrease was accompanied by an increase in the number of wild-type revertants. Adenine accelerated the growth of producing strain HT-2892 to nearly equal that of revertants, and histidine production was stable because the depletion(More)
Arginine productivity of an arginine-producing mutant of Serratia marcescens decreased during successive batch culturing. The mutant grew more slowly than the parent strains in a minimal medium, and spontaneously produced derivatives that grew more rapidly than the mutant. A large majority of the derivatives required N-acetylglutamate or arginine for(More)
In Serratia marcescens, the mutation responsible for triazolealanine (TRA) resistance was transferred from a TRA-resistant mutant to a urocanase-less mutant by PS20-mediated transduction. The two crosses were performed using as donors two TRA-resistant mutants, whose phenotypes included increased levels of histidine-biosynthetic enzymes and(More)
The biosynthetic pathways of norvaline homoisoleucine were examined using regulatory mutants of leucine biosynthesis in Serratia marcescens. alpha-Isopropylmalate synthetase [EC 4.1.3.12], the first enzyme of leucine biosynthesis, catalyzed the condensations of acetyl-CoA with pyruvate, alpha-ketobutyrate, alpha-ketovalerate, or(More)