期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1978
卷号:75
期号:6
页码:2579-2583
DOI:10.1073/pnas.75.6.2579
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:By use of the technique of flow dialysis, the membrane potential (deltapsi) and pH gradient (deltapH) have been measured in colicin Ia-treated Escherichia coli K-12 cells and in membrane vesicles prepared from such cells. Although such cells and vesicles are able to generate a transmembrane deltapH at pH 5.5, they do not generate a transmembrane deltapsi. Glucose-6-phospate uptake by cells is shown to be stimulated at pH 5.5 and inhibited at pH 7.5 by colicin Ia treatment. On the other hand, proline uptake is demonstrated to be inhibited progressively at pH 5.5, 6.6, and 7.5 in colicin Ia-treated cells. These data provide strong evidence for a colicin Ia-induced membrane deplorization and indicate that the membrane becomes permeable to ion(s) other than protons after treatment with colicin Ia.