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：1981
卷号：78
期号：9
页码：5358-5361
DOI：10.1073/pnas.78.9.5358
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Transport of D-glucose was examined in membrane vesicles from normal and avian sarcoma virus (ASV)-transformed chicken embryo fibroblasts. The initial rates of D-glucose transport were found to be 3- to 5-fold higher for vesicles from glucose-starved normal cells and ASV-transformed cells when compared with transport rates for vesicles from normal cells and serum-starved normal cells. Cytochalasin B, phloretin, and diethylstilbestrol inhibited the initial rate of transport in all types of vesicles, and 2-deoxyglucose, 3-O-methylglucose, and galactose were competitive inhibitors. At D-glucose concentrations between 0.25 and 5 mM, vesicles from normal and ASV-transformed cells displayed saturation kinetics with a Km value of 5 mM for both types of vesicles, with transformed cell vesicles showing a 3-fold increase in Vmax compared with normal cell vesicles. At D-glucose concentrations between 5 and 25 mM the initial rate of D-glucose transport was proportional to D-glucose concentration. The vesicles also showed an inhibitor-sensitive efflux at rates similar to those observed for influx.
