Hodgson D, Shaw P, O'Connell M, Henry S, Shapiro L
J Bacteriol. 1984 Apr;158(1):156-62. doi: 10.1128/jb.158.1.156-162.1984.
A fatty acid auxotroph of Caulobacter crescentus, AE6001, which displays a strict requirement for unsaturated fatty acids to grow on glucose as the carbon source has been isolated. Starvation of AE6001 for unsaturated fatty acids resulted in a block in the cell cycle. Starved cultures accumulated at the predivisional cell stage after a round of DNA replication had been completed and after a flagellum had been assembled at the pole of the cell. Cell division and cell growth failed to occur probably because the mutant was unable to synthesize a membrane. An analysis of double mutants containing the fatB503 allele and other mutations in membrane biogenesis demonstrated that the cell cycle of AE6001 blocked at a homeostatic state. The addition of oleic acid to starved cultures permitted cell division and the initiation of a new round of DNA replication. The coincident block in both the initiation of DNA replication and membrane assembly, exhibited by starved cultures of this mutant, suggests that the fatB503 gene product may be involved in the coordination of these events.
已分离出新月柄杆菌的脂肪酸营养缺陷型菌株AE6001，该菌株在以葡萄糖作为碳源生长时对不饱和脂肪酸有严格需求。使AE6001缺乏不饱和脂肪酸会导致细胞周期阻滞。饥饿培养物在一轮DNA复制完成后以及鞭毛在细胞极组装后，会在细胞分裂前阶段积累。细胞分裂和细胞生长可能无法发生，原因可能是该突变体无法合成细胞膜。对含有fatB503等位基因和膜生物合成中其他突变的双突变体进行分析表明，AE6001的细胞周期在稳态下受阻。向饥饿培养物中添加油酸可使细胞分裂并启动新一轮DNA复制。该突变体饥饿培养物所表现出的DNA复制起始和膜组装同时受阻，表明fatB503基因产物可能参与了这些事件的协调。
