2-Amino-5-methyl-5-hexenoic acid, a methionine analog produced by Streptomyces sp. MF374-C4.
作者:MIEKO TAKEUCHI、HIRONOBU IINUMA、TOMIO TAKEUCHI、HAMAO UMEZAWA、KAYOKO SUZUKAKE、MAKOTO HORI
DOI:10.7164/antibiotics.32.1118
日期:——
2-Amino-5-methyl-5-hexenoic acid (AMHA), a new methionine analog, was isolated from a fermentation broth of Streptomyces sp. MF374-C4 based on its reversal of the effect of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in a test system that determines the size of growth zones of revertants (His+) of Salmonella typhimurium TA 1535. AMHA also inhibited growth of the tester strain in a synthetic medium. These AMHA activities were abolished by methionine. The incidence of spontaneous streptomycin-resistant mutations of Escherichia coli K12 was not decreased by AMHA at concentrations where cell growth was partially inhibited. AMHA inhibited protein synthesis but not DNA or RNA synthesis in S. typhimurium TA1535 and E. coli K-12. The analog inhibited formation of methionyl-tRNA but not of valyl-tRNA in a cell-free system of E. coli, and supported ATP-PPi exchange in the cell-free system. At concentrations where it inhibited cell growth, AMHA decreased the number of foci, induced by ROUS sarcoma virus, on cultured sheets of chick-embryo fibroblasts. The effects of AMHA on focus formation and on the cell growth were overcome by methionine.
2-Amino-5-methyl-5-hexenoic acid(AMHA)是一种新的蛋氨酸类似物,它是从链霉菌 MF374-C4 的发酵液中分离出来的,其依据是在确定鼠伤寒沙门氏菌 TA 1535 的逆转菌(His+)生长区大小的测试系统中,AMHA 可逆转 N-甲基-N'-硝基-N-亚硝基胍(MNNG)的作用。AMHA 还能抑制试验菌株在合成培养基中的生长。蛋氨酸可抑制 AMHA 的这些活性。在部分抑制细胞生长的浓度下,AMHA 不会降低大肠杆菌 K12 的自发链霉素抗性突变的发生率。AMHA 可抑制伤寒杆菌 TA1535 和大肠杆菌 K-12 的蛋白质合成,但不能抑制 DNA 或 RNA 合成。在大肠杆菌的无细胞系统中,该类似物抑制蛋氨酰-tRNA 的形成,但不抑制缬氨酰-tRNA 的形成,并支持无细胞系统中的 ATP-PPi 交换。在抑制细胞生长的浓度下,AMHA 可减少由 ROUS 肉瘤病毒诱导的小鼠胚胎成纤维细胞培养片上的病灶数量。蛋氨酸可以克服 AMHA 对病灶形成和细胞生长的影响。