アミノ酸拮抗物質の研究 (第11報)
微生物におけるイソロイシンとバリンの拮抗およびそれに対するロイシンの影響
1959 年 79 巻 4 号 p. 483-487
詳細
1959 年 79 巻 4 号 p. 483-487
By irradiation of ultraviolet ray on Escherichia coli K 12-W, a double-requiring mutant iv-17, requiring isoleucine and valine, was isolated. The genetic block of this strain is between hydroxy acid to keto acid. Its growth was inhibited by excess of isoleucine and antagonized by valine. Growth inhibition by isoleucine was examined with the iv-17 strain and 11A16, M 42-37, 20A19, 48-62, and 92-21 strains of E. coli, and 16117 and 7110 strains of Neurospora crassa. Of these, 20A19 and 48-62 strains of E. coli and both of N. crassa were inhibited and these strains were characterized by strict requirement of valine. Inhibitory action of isoleucine in E. coli iv-17 was recovered by addition of leucine and this phenomenon was observed in other microörganisms whose growth is inhibited by isoleucine. Ketoleucine was also found to have this action.
