Listeria monocytogenes Scott A Transports Glucose by High-Affinity and Low-Affinity Glucose Transport Systems

Authors

Corinne Parker, University of Nebraska-Lincoln
Robert W. Hutkins, University of Nebraska-LincolnFollow

Date of this Version

February 1997

Comments

Published in APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Feb. 1997, p. 543–546 Vol. 63, No. 2. Copyright 1997, American Society for Microbiology. Used by permission.

Abstract

Listeria monocytogenes transported glucose by a high-affinity phosphoenolpyruvate-dependent phosphotransferase system and a low-affinity proton motive force-mediated system. The low-affinity system (K_m = 2.9 mM) was inhibited by 2-deoxyglucose and 6-deoxyglucose, whereas the high-affinity system (K_m= 0.11 mM) was inhibited by 2-deoxyglucose and mannose but not 6-deoxyglucose. Cells and vesicles artificially energized with valinomycin transported glucose or 2-deoxyglucose at rates greater than those of de-energized cells, indicating that a membrane potential could drive uptake by the low-affinity system.