Research Article Sliding Motility, Biofilm Formation, and Glycopeptidolipid Production in Mycobacterium colombiense Strains

Copyright © 2015 Milena Maya-Hoyos et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mycobacterium colombiense is a novel member of theMycobacterium avium complex, which produces respiratory and disseminated infections in immunosuppressed patients. Currently, the morphological and genetic bases underlying the phenotypic features of M. colombiense strains remain unknown. In the present study, we demonstrated that M. colombiense strains displaying smooth morphology show increased biofilm formation on hydrophobic surfaces and sliding onmotility plates.Thin-layer chromatography experiments showed that M. colombiense strains displaying smooth colonies produce large amounts of glycolipids with a chromatographic behaviour similar to that of the glycopeptidolipids (GPLs) of M. avium. Conversely, we observed a natural rough variant of M. colombiense (57B strain) lacking pigmentation and exhibiting impaired sliding, biofilm formation, and GPL production. Bioinformatics analyses revealed a gene cluster that is likely involved in GPL biosynthesis in M. colombiense CECT 3035. RT-qPCR experiments showed that motile culture conditions activate the transcription of genes possibly involved in key enzymatic activities of GPL biosynthesis. 1