Mycoplasma incognitus
A Microbial Biorealm page on the genus Mycoplasma incognitus
Classification
Higher order taxa
Bacteria; Tenericutes; Mollicutes; Mycoplasmatales; Mycoplasmataceae; Mycoplasma
Species
M. incognitus
Description and significance
Mycoplasma incognitus is a human cell invasive mycoplasma associated with several human diseases including AIDS and Rheumatoid Arthritis. M. incognitus is an immunomodulatory agent, which means it can alter the immune response by reducing the ability of the immune system to produce antibodies. This mycoplasma is highly pathogenic and can be passed from person to person via bodily fluids.
Genome structure
Mycoplasma incognitus acts as a parasite and gains most of its nutrients from its host. Due to this parasitic mode of life, M. incognitus has a very small genome consisting of only the genes essential for life. It is estimated that this microbe has less than 500 genes and could have a genome as small as 600 kb. Evolution and adaptation has allowed this microbe to lose the genes necessary for many assimilative processes.
Cell and Colony Structure
There have been frequent unsuccessful attempts at isolating a culture of M. incognitus, but it is known that the most frequently colonized sites are epithelial cell surfaces.
Metabolism
M. incognitus can utilize glucose both aerobically and anaerobically, and can metabolize arginine.
M. incohnitus is an obligate pathogen and cannot survive unless it is inside a host.
Pathology
M. incognitus is able to control a person's immune response and can either stimulate or suppress lymphocytes. It can also modulate the activities of monocytes, macrophages, and NK cells. Mycoplasma-mediated secretion of proinflammatory cytokines by macrophages, and up-regulating cytokines by lymphocytes, plays a major role in the inflammatory response.
References
Molecular Biology and Pathogenicity of Mycoplasmas. Shmuel Razin, David Yogev, Yehudith Naot. Microbial Mol Biol Rev. 1998 December; 62(4): 1094-1156.
Genotypic Characterization of Seven Strains of Mycoplasma fermentans Isolated from Synovial Fluids of Patients With Arthritis. Thierry Schaeverbeke et al. J Clin Microbiol. 1998 May: 36(5): 1226-1231; www.ncbi.nlm.nih.gov/pmc/articles/PMC104804/
Genotypic and Phenotypic Analysis of Mycoplasma fermentans Strains Isolated From Different Host Tissues. Laura Campo, Patrick Larocque, Tiziana La Malfa et al. J Clin Microbiol. 1998 May; 36(5): 1371-1377; www. ncbi.nlm.nih.gov/pmc/articles/PMC104831/
Edited by Keisha Picknell of Dr. Lisa R. Moore, University of Southern Maine, Department of Biological Sciences, http://www.usm.maine.edu/bio
