Genetic studies on the inability of beta-galactosidase to be translocated across the Escherichia coli cytoplasmic membrane
Genetic studies on the inability of beta-galactosidase to be translocated across the Escherichia coli cytoplasmic membrane
复制标题
β-半乳糖苷酶不能穿过大肠杆菌细胞质膜的遗传学研究
DOI：
10.1128/jb.171.9.4609-4616.1989
复制
发表时间：
1989
影响因子：
3.2
通讯作者：
J. Beckwith
中科院分区：
文献类型：
--
作者：
Catherine A. Lee;Ping Li;H. Inouye;E. Brickman;J. Beckwith
When a signal sequence is attached to beta-galactosidase, the normally cytoplasmic protein is unable to fully traverse the cytoplasmic membrane. We used a genetic approach to study those features of beta-galactosidase responsible for the block in translocation. By using both in vivo and in vitro techniques, fragments of beta-galactosidase were interposed between a signal sequence and alkaline phosphatase. The alkaline phosphatase acts as a sensor for any blocking effects of beta-galactosidase on export. From these studies, we show that multiple regions of beta-galactosidase contribute to its failure to be translocated. These results are most easily interpreted if the folding of beta-galactosidase or of domains of it is responsible for the block in export. In addition, in certain constructs, positively charged amino acids directly following the signal sequence interfered with export.
