Identification of a Glucose Permease from Mycobacterium smegmatis mc(2) 155

Abstract

We report here the molecular identification of a glucose permease from Mycobacterium smegmatis, a model organism for our understanding of the life patterns of the major pathogens Mycobacterium tuberculosis and Mycobacterium leprae. A computer-based search of the available genome of M. smegmatis mc(2) 155 with the sequences of well-characterized glucose transporters revealed the gene msmeg4187 as a possible candidate. The deduced protein belongs to the major facilitator superfamily of proton symporters and facilitators and exhibits up to 53% of amino acid identity to other members of this family. Heterologous expression of msmeg4187 in an Escherichia coli glucose-negative mutant led to the restoration of growth on glucose. The determination of the biochemical features characterize MSMEG4187 (GlcP) as a high affinity (K m of 19 mu M), glucose-specific permease. The results represent the first molecular characterization of a sugar permease in mycobacteria, and thus supply fundamental data for further in-depth analysis on the nutritional lifestyle of these bacteria. Copyright (C) 2008 S. Karger AG, Basel