DIFFERENTIAL-EFFECTS OF ETHANOL AND HEXANOL ON THE ESCHERICHIA-COLI CELL-ENVELOPE
DIFFERENTIAL-EFFECTS OF ETHANOL AND HEXANOL ON THE ESCHERICHIA-COLI CELL-ENVELOPE
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DOI：
10.1128/jb.144.2.481-488.1980
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发表时间：
1980-01-01
影响因子：
3.2
通讯作者：
VREELAND, NS
中科院分区：
文献类型：
--
作者：
INGRAM, LO;VREELAND, NS
乙醇和己醇均能抑制大肠杆菌的生长，但对细胞包膜组织和组成的影响有很大差异。己醇(7.8倍。10-3 mM)增加了膜的流动性，而乙醇（0.67 M）影响不大。在乙醇存在下的生长过程中，不饱和脂肪酸的比例增加。己醇则引起相反的变化。与己醇不同的是，在乙醇存在下的生长导致产生未交联的肽聚糖，随后进行裂解。盐（0.3 M）保护细胞免受乙醇诱导的裂解，但增强了己醇对生长的抑制作用。对乙醇诱导裂解产生抗性的突变体在乙醇存在下的生长过程中合成了交联肽聚糖，但对己醇仍然敏感。提出了一个一般的假设来解释乙醇和己醇的不同作用。所有醇都被认为是相似的，因为它们都具有能够与疏水环境相互作用的极性链和能够形成氢键的羟基功能。短链醇的差异效应可能是由于环境中具有极性的氢键基团的高摩尔浓度造成的。在某些情况下，这些水可以代替结合水。对于像己醇这样的长链醇，酰基链的作用将占主导地位，而溶解度和细胞完整性的限制将掩盖这些羟基的作用。
Both ethanol and hexanol inhibited the growth of E. coli, but their effects on the organization and composition of the cell envelope were quite different. Hexanol (7.8 .times. 10-3 mM) increased membrane fluidity, whereas ethanol (0.67 M) had little effect. During growth in the presence of ethanol, the proportion of unsaturated fatty acids increased. The opposite change was induced by hexanol. Unlike hexanol, growth in the presence of ethanol resulted in the production of un-cross-linked peptidoglycan with subsequent lysis. Salt (0.3 M) protected cells against ethanol-induced lysis but potentiated growth inhibition by hexanol. Mutants isolated for resistance to ethanol-induced lysis synthesized cross-linked peptidoglycan during growth in the presence of ethanol but remained sensitive to hexanol. A general hypothesis was presented to explain the differential effects of ethanol and hexanol. All alcohols are viewed as similar in having both an apolar chain capable of interacting with hydrophobic environments and a hydroxyl function capable of H bonding. The differential effects of short-chain alcohols may represent effects due to the high molar concentrations of H bonding groups with an apolar end within the environment. These may replace bound water in some cases. With longer-chain alcohols such as hexanol, the effects of the acyl chain would dominate, and limitations of solubility and cellular integrity would mask these hydroxyl effects.