RELEASE OF OUTER MEMBRANE FRAGMENTS FROM NORMALLY GROWING ESCHERICHIA-COLI
RELEASE OF OUTER MEMBRANE FRAGMENTS FROM NORMALLY GROWING ESCHERICHIA-COLI
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DOI：
10.1016/0005-2736(76)90058-4
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发表时间：
1976-01-01
期刊：
影响因子：
--
通讯作者：
WITHOLT, B
中科院分区：
文献类型：
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作者：
HOEKSTRA, D;VANDERLAAN, JW;WITHOLT, B
含有脂多糖、磷脂和蛋白质的复合物被E.大肠杆菌正常生长。它可以通过Sephadex G-200上的凝胶过滤或通过离心从培养基中分离。EM显示，该物质以囊泡和膜碎片的形式释放。为了确定这些片段的起源，他们进行了比较，外和细胞质膜相对于酮-脱氧辛酮糖酸，磷脂，蛋白质含量，磷脂成分，脂肪酸成分，蛋白质分布在十二烷基硫酸钠-聚丙烯酰胺凝胶，浮力密度，和几种膜标记酶的含量。比较结果表明，正常生长的大肠杆菌培养上清中的膜碎片与正常生长的大肠杆菌培养上清中的膜碎片不同。大肠杆菌由几乎未修饰的外膜组成。外膜碎片的释放及其与细胞分裂的关系的原因的可能机制进行了讨论。
A complex containing lipopolysaccharides, phospholipids and proteins is released into the culture medium by E. coli during normal growth. It can be separated from the medium by gel filtration on Sephadex G-200 or by centrifugation. EM revealed that this material is released as vesicles and membrane fragments. To determine the origin of these fragments, they were compared to outer and cytoplasmic membranes with respect to keto-deoxyoctulosonic acid, phospholipid, and protein content, phospholipid composition, fatty acid composition, protein distribution on sodium dodecyl sulfate-polyacrylamide gels, buoyant density, and content of several membrane marker enzymes. The results of this comparison indicate that the membrane fragments found in the culture supernatant of normally growing E. coli consist of practically unmodified outer membrane. Possible mechanisms as to the cause of the release of outer membrane fragments and its relationship to cell-division are discussed.