A bacterium with the species name genitalium is sure to drive fear into the hearts of all sexually reproducing organisms. And indeed, there is reason to fear. M. genitalium is parasite that makes its home in the ciliated epithelial cells of primate genital and respiratory tracts (Mycoplasma genitalium wikipedia). It is rumored to cause non-gonococcal urethritis. Nevertheless, this is hardly a deadly bacterium.
Its genus name reveals more aspects about its nature. Myco-, meaning fungi-like, reveals its method of attaching itself to host cells. Adhesin protein is produced and a fungi-like filamentous network is constructed to adhere this parasite to its host. This is one of its most useful adaptations because with it, it can keep close to environments that are conducive to survival and growth. Indeed, this bacteria’s optimal growing temperature is 37C. It even requires that cholesterol be present in its environment for its survival. This is a most odd adaptation in general but a quite usual one for a parasite.
When M. genitalium’s whole genome was sequenced by Fraser in 1995 (Fraser, et. al., 1995), it became known as the smallest genome around. It had lost so much cellular machinery through evolving inside a particular host that it was now the smallest known self-replicating, free-living organism. They have a total of 580 kpb and around 470 genes. In addition to losing its ability to survive without cholesterol (or produce it itself), it has lost its cell wall. Nevertheless, it still stains Gram positive.
Since M. genitalium was originally isolated from urethral specimens of patients with non-gonococcal urethritis, it has been studied for its simplicity. Although it can sometimes be a pest when it infects cell cultures because of its tiny size (0.2um) or certain primates’ urinary tracts, it is a blessing in disguise. As is the case in all sciences, the simplest cases usually get studied first. M. genitalium has aided science by providing a simple genome to be sequenced, analyzed, studied and understood.
References:
Fraser, C. M., J. D. Gocayne, O. White, M. D. Adams, R. A. Clayton, R. D. Fleischmann, C. J. Bult, A. R. Kerlavage, G. Sutton, J. M. Kelley, and a. et. 1995. The minimal gene complement of Mycoplasma genitalium. Science 270:397-403.
Mycoplasma. Retrieved Feb 13, 2006, from http://en.wikipedia.org/wiki/Mycoplasma
Mycoplasma genitalium. Retrieved Feb 13, 2006, from http://en.wikipedia.org/wiki/Mycoplasma_genitalium
What is ‘myco?’ Retrieved Feb 13, 2006, from http://www.ratlovers.org/articles/Myco.html
*Disclaimer - This report was written by a student participaring in a microbiology course at the Missouri University of Science and Technology. The accuracy of the contents of this report is not guaranteed and it is recommended that you seek additional sources of information to verify the contents.
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