Johnson R C, Ferber D M, Ely B
J Bacteriol. 1983 Jun;154(3):1137-44. doi: 10.1128/jb.154.3.1137-1144.1983.
Cultures of wild-type Caulobacter crescentus and strains with fla mutations representing 24 genes were pulse-labeled with 14C-amino acids and analyzed by immunoprecipitation to study the synthesis of flagellar components. Most fla mutants synthesize flagellin proteins at a reduced rate, suggesting the existence of some mechanism to prevent the accumulation of unpolymerized flagellin subunits. Two strains contain deletions that appear to remove a region necessary for this regulation. The hook protein does not seem to be subject to this type of regulation and, in addition, appears to be synthesized as a faster-sedimenting precursor. Mutations in a number of genes result in the appearance of degradation products of either the flagellin or the hook proteins. Mutations in flaA, -X, -Y, or -Z result in the production of filaments (stubs) that contain altered ratios of the flagellin proteins. In some flaA mutants, other flagellin-related proteins were assembled into the stub structures in addition to the flagellins normally present. Taken together, these analyses have begun to provide insight into the roles of individual fla genes in flagellum biogenesis in C. crescentus.
用¹⁴C - 氨基酸对野生型新月柄杆菌以及代表24个基因的fla突变菌株进行脉冲标记，并通过免疫沉淀法进行分析，以研究鞭毛成分的合成。大多数fla突变体以较低的速率合成鞭毛蛋白，这表明存在某种机制来防止未聚合的鞭毛蛋白亚基的积累。有两个菌株存在缺失，这些缺失似乎去除了这种调控所必需的区域。钩蛋白似乎不受这种类型的调控，此外，它似乎是以沉降速度更快的前体形式合成的。许多基因的突变会导致鞭毛蛋白或钩蛋白降解产物的出现。flaA、-X、-Y或-Z基因的突变会导致产生含有改变的鞭毛蛋白比例的细丝（残段）。在一些flaA突变体中，除了正常存在的鞭毛蛋白外，其他与鞭毛蛋白相关的蛋白质也被组装到残段结构中。综合起来，这些分析已经开始为深入了解单个fla基因在新月柄杆菌鞭毛生物合成中的作用提供了线索。
