A genomic view of sugar transport in Mycobacterium smegmatis and Mycobacterium tuberculosis.
We present a comprehensive analysis of carbohydrate uptake systems of the soil bacterium Mycobacterium smegmatis and the human pathogen Mycobacterium tuberculosis. Our results show that M. smegmatis has 28 putative carbohydrate transporters. The majority of sugar transport systems (19/28) in M. smegmatis belong to the ATP-binding cassette (ABC) transporter family. In contrast to previous reports, we identified genes encoding all components of the phosphotransferase system (PTS), including permeases for fructose, glucose, and dihydroxyacetone, in M. smegmatis. It is anticipated that the PTS of M. smegmatis plays an important role in the global control of carbon metabolism similar to those of other bacteria. M. smegmatis further possesses one putative glycerol facilitator of the major intrinsic protein family, four sugar permeases of the major facilitator superfamily, one of which was assigned as a glucose transporter, and one galactose permease of the sodium solute superfamily. Our predictions were validated by gene expression, growth, and sugar transport analyses. Strikingly, we detected only five sugar permeases in the slow-growing species M. tuberculosis, two of which occur in M. smegmatis. Genes for a PTS are missing in M. tuberculosis. Our analysis thus brings the diversity of carbohydrate uptake systems of fast- and a slow-growing mycobacteria to light, which reflects the lifestyles of M. smegmatis and M. tuberculosis in their natural habitats, the soil and the human body, respectively.
Titgemeyer
Fritz
F
Lehrstuhl für Mikrobiologie, Friedrich Alexander Universität Erlangen-Nürnberg, Staudtstrasse 5, D-91058 Erlangen, Germany. fritz.titgemeyer@googlemail.com
Amon
Johannes
J
Parche
Stephan
S
Mahfoud
Maysa
M
Bail
Johannes
J
Schlicht
Maximilian
M
Rehm
Nadine
N
Hillmann
Dietmar
D
Stephan
Joachim
J
Walter
Britta
B
Burkovski
Andreas
A
Niederweis
Michael
M
D001692:Biological Transport; D050260:Carbohydrate Metabolism; D002241:Carbohydrates; D015964:Gene Expression Regulation, Bacterial; D026901:Membrane Transport Proteins / Q000378:metabolism*; D020102:Mycobacterium smegmatis / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D009169:Mycobacterium tuberculosis / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000378:metabolism*
D002241:Carbohydrates; D026901:Membrane Transport Proteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System