Kusser W C, Ishiguro E E
Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada.
Antimicrob Agents Chemother. 1988 Aug;32(8):1247-50. doi: 10.1128/AAC.32.8.1247.
The effects of aminoglycosides and spectinomycin on lipopolysaccharide (LPS) synthesis and release by Escherichia coli were studied. LPS synthesis was previously reported to be regulated by the stringent control mechanism. In agreement with this, the control of LPS synthesis in amino acid-deprived relA+ cells was relaxed by spectinomycin, a proven stringent control antagonist, but not by kanamycin, an agent which is ineffective as a stringent control antagonist. The other stringent control antagonists tested (gentamicin, tobramycin, and, to a lesser extent, amikacin) unexpectedly failed to relax the control of LPS synthesis, and this was subsequently shown to be due to their inhibitory action on LPS synthesis. The release of LPS by nongrowing (amino acid-deprived and antibiotic-treated) bacteria was stimulated only under conditions in which the control of LPS synthesis was relaxed.
研究了氨基糖苷类药物和壮观霉素对大肠杆菌脂多糖(LPS)合成及释放的影响。此前有报道称LPS合成受严谨控制机制调控。与此相符的是,在氨基酸缺乏的relA+细胞中,作为已证实的严谨控制拮抗剂的壮观霉素可使LPS合成的控制得到松弛,但作为严谨控制拮抗剂无效的卡那霉素则不能。所测试的其他严谨控制拮抗剂(庆大霉素、妥布霉素以及程度较轻的阿米卡星)意外地未能使LPS合成的控制得到松弛,随后发现这是由于它们对LPS合成具有抑制作用。仅在LPS合成的控制得到松弛的条件下,非生长状态(氨基酸缺乏且经抗生素处理)细菌释放LPS的过程才会受到刺激。