Yu C, Lee A M, Roseman S
McCollum-Pratt Institute, Johns Hopkins University, Baltimore, Maryland 21218.
Biochem Biophys Res Commun. 1987 Nov 30;149(1):86-92. doi: 10.1016/0006-291x(87)91608-1.
Our earlier studies on cell adhesion to immobilized carbohydrates are extended here to a marine bacterium, Vibrio furnissii. Apparently one lectin mediates the binding of these cells to glycosides of N-acetylglucosamine, mannose, and glucose covalently linked to Agarose beads. Kinetic studies show that protein synthesis is required for initiating and for maintaining adhesion to the glycosides. Furthermore, a pro- mutant binds to GlcNAc-beads at Pro concentrations insufficient to support cell growth. Expression of the functional lectin therefore predominates under conditions of limiting protein synthesis. Thus, cells adhere to the sugars in an environment compatible with protein synthesis, and deadhere when depleted of any required nutrient, presumably to migrate to a more favorable locale. The adhesion-deadhesion apparatus thereby permits constant monitoring of the surrounding environment, comprising a "nutrient sensorium".
我们早期关于细胞与固定化碳水化合物黏附的研究在此扩展至一种海洋细菌——弗氏弧菌。显然,一种凝集素介导了这些细胞与共价连接到琼脂糖珠上的N - 乙酰葡糖胺、甘露糖和葡萄糖的糖苷的结合。动力学研究表明,蛋白质合成对于启动和维持与糖苷的黏附是必需的。此外,一个脯氨酸突变体在脯氨酸浓度不足以支持细胞生长时仍能与GlcNAc - 珠结合。因此,在蛋白质合成受限的条件下,功能性凝集素的表达占主导。这样,细胞在与蛋白质合成兼容的环境中黏附于糖类,而当耗尽任何所需营养时则脱黏附,大概是为了迁移到更有利的场所。这种黏附 - 脱黏附机制从而允许对周围环境进行持续监测,构成了一个“营养感受器”。