GENETICS AND PHYSIOLOGY OF COLICIN-TOLERANT MUTANTS OF ESCHERICHIA COLI
GENETICS AND PHYSIOLOGY OF COLICIN-TOLERANT MUTANTS OF ESCHERICHIA COLI
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DOI：
10.1128/jb.94.4.1112-1123.1967
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发表时间：
1967-01-01
影响因子：
3.2
通讯作者：
LURIA, SE
中科院分区：
文献类型：
--
作者：
DEZWAIG, RN;LURIA, SE
从大肠杆菌K-12中分离到一系列能吸附大肠杆菌素而不被其杀死的大肠杆菌素耐受突变株，并对其进行了遗传和生理学研究。发现了三种主要的突变体：tol II，耐受大肠杆菌素A，E1，E2，E3和K;tol III，耐受A，E2，E3和K;和tol VIII，仅耐受E1。tol II和tol III突变位点定位在galregion附近（基因顺序：tol-gal-bio），并与galby P1共转导。在杂合二倍体中，tol+为显性，tol Ⅱ和tol Ⅲ为完全互补。所有在gal附近定位的thetol突变使细菌在生长过程中更加脆弱，对脱氧胆酸盐和乙二胺四乙酸超敏感。第八个突变定位于股间。这些突变体对脱氧胆酸盐极其敏感，对亚甲蓝、吖啶和各种其他化合物也非常敏感。敏感性归因于由于渗透性屏障的选择性改变而增加的摄取。大肠杆菌素耐受性突变被解释为影响细胞质膜的某些组分，这些组分在吸附的大肠杆菌素分子和它们在细菌细胞中的生化作用的靶位点之间介导。
A series of colicin-tolerant (tol) mutants ofEscherichia coliK-12, which adsorbed colicins but were not killed by them, were isolated and studied genetically and physiologically. Three major classes of mutants were found:tol II, tolerant to colicins A, E1, E2, E3, and K;tol III, tolerant to A, E2, E3, and K; andtol VIII, tolerant to E1 only. The sites oftol IIandtol IIImutations mapped near thegalregion (gene order:tol-gal-bio) and were cotransduced withgalby P1. In heterozygous diploids,tol+was dominant overtol;tol IIandtol IIIgave full complementation. All thetolmutations that mapped neargalrendered the bacteria more fragile during growth and hypersensitive to deoxycholate and to ethylenediaminetetraacetic acid. Thetol VIIImutation mapped betweenstrandhis. These mutants were extremely sensitive to deoxycholate and were also hypersensitive to methylene blue, acridines, and various other compounds. The sensitivity is attributed to increased uptake due to selective alteration of the permeability barrier. The colicin-tolerant mutations are interpreted as affecting some components of the cytoplasmic membrane which mediate between the adsorbed colicin molecules and the target sites of their biochemical effects in the bacterial cell.