The Mannose Transporter Complex: an Open Door for the Macromolecular Invasion of Bacteria

Abstract

In this issue of the Journal of Bacteriology, Bieler et al. demonstrate (i) that the toxic activity of microcin E492 is independent of the “route of administration,” viz. whether it is added from the outside (as in nature) or expressed endogenously in the cytoplasm, and (ii) that microcin E492 requires the transporter for mannose to deploy its ion channel-forming activity. This is the strongest and most direct evidence to date that the mannose transporter is involved in microcin activity in gram-negative enterobacteria.