Mycoplasma hominis adaptation mechanisms to new niches

Mycoplasma hominis is a bacterium belonging to the class Mollicutes. It causes acute and chronic infections of the urogenital tract. The main features of this bacterium are an absence of cell wall and a reduced genome size. Previously, we isolated morphologically unknown M. hominis colonies called micro-colonies (MCs) from serum of patients with inflammatory urogenital tract infection. The diameter of MCs cells was 25 times smaller than that of classic (typical) colonies (CCs). We assume that MC cells preferably utilized deoxyribonucleosides, particularly thymidine, as energy source rather than arginine or ribonucleosides. Thymidine phosphorylase DeoA is one of the key enzymes of deoxyribonucleosides utilization. We obtained a DeoA overexpressing mutant that exhibited a phenotype similar to that of MCs, which confirmed our hypothesis.