Carty C E, Ingram L O
J Bacteriol. 1981 Jan;145(1):472-8. doi: 10.1128/jb.145.1.472-478.1981.
Lipid synthesis was examined in Escherichia coli cells at different stage of cell division. Exponentially growing cells were pulse-labeled with appropriate isotopes for 0.1 generation time, inactivated, and separated by size on a sucrose gradient. An abrupt increase in the rate of lipid synthesis occurred which was coincident with the initiation of cross walls. In contrast, the rate of protein synthesis during this same interval remained constant, resulting in an increased lipid/protein ratio in dividing cells. No changes in the composition of phospholipid head groups, fatty acids, or phospholipid molecular species were observed in cells at different stages of division. The observed increase in the rate of lipid synthesis may reflect a means by which the activities of membrane-associated enzymes are modulated during cross wall formation.
在大肠杆菌细胞分裂的不同阶段对脂质合成进行了研究。对数生长期的细胞用适当的同位素脉冲标记0.1代时间，使其失活，然后在蔗糖梯度上按大小分离。脂质合成速率突然增加，这与横壁的起始同时发生。相比之下，在同一时间段内蛋白质合成速率保持恒定，导致分裂细胞中脂质/蛋白质比率增加。在细胞分裂的不同阶段，未观察到磷脂头部基团、脂肪酸或磷脂分子种类的组成发生变化。观察到的脂质合成速率增加可能反映了一种在横壁形成过程中调节膜相关酶活性的方式。
