Mycoplasma capricolum

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A Microbial Biorealm page on the genus Mycoplasma capricolum

Classification

Higher order taxa

Cellular organisms; Bacteria; Firmicutes; Mollicutes; Mycoplasmatales; Mycoplasmataceae; Mycoplasma

Species

Mycoplasma capricolum


NCBI: Taxonomy

Description and significance

Mycoplasma capricolum belongs to the genus Mycoplasma, which is a genus of bacteria that does not have cell wall neither murein. This spherical organism is distinguished from other bacteria by its small size (a characteristic of the genus Mycoplasma) and requirement of cholesterol for growth. However, its DNA structure suggests that Mycoplasma capricolum is derivative of Gram positive bacteria.[8]Though hard to isolate, this microorganism still can be obtained from lungs and pleural fluid of affected animals in necropsy and cultured in cholesterol and serum-containing medium readily[9].

Genome structure

The size the circular genome of Mycoplasma capricolum is 1155.5 kb, and has 25% of GC content, which is relatively low compared to other organisms. This organism has only one chromosome. Though plasmid is unusal among Mycoplasma species, M. capricolum is found to have plamid whose size is around 1.1kb-1.8kb.The extrachromosomal DNA may contribute to antimicrobial resistance since it is found more often in herds that have undergone the use of antimicrobial drugs.[7]

Cell structure and metabolism

M. capricolum has no cell wall but only lipid bilayer membrane, up to 2/3 of unesterified cholesterol is in the outer membrane. It requires cholesterol for growth, but the uptaken fatty acid is not used as substrate for energy production but for phospholipd syntesis. Experiments also suggest that fatty acid incorporation process is influenced by the concentration of glucose and glycerol, temperature and external pH.[10] Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.

Ecology

The natural transmission pathway of M. capricolum is through inhalation of infectious droplets, though infection could be achieved through injecting cell culture experimentally. When inhaled, it is bound by the cell membrane and its surface-exposing lipoproteins induce strong antigenic reactions. However, its sophisticated antigenic variation makes it hard for the host immune system to produce proper antibody to suppress the infection. An extracellular polysaccharide structure may have capsule-like funcion. Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.

Pathology

M capricolum is a causative agents of caprine respiratory diseases, mastitis and severe arthritis, and the infection often leads destructive result in Africa and Asia goat farming industry. Fever is also observed at the end of incubation period. Some subspecies of Mycoplasma capricolum, for example,M. capricolum subsp. mycoides and M. capricolum subsp.capripneumoniae are especially virulent. The morbidity and mortality rate of some subspecies is of 60%-70%. Long-term survival is possible but often accompanied with pleuropneumonia or chronic pleurutis. This bacterium is capable of stimulating macrophage to produce oxygen radicals, TNF-α, IL-6 and nitric oxide. This combination leads the production of peroxynitrite, a very strong oxidant.[4] For the subspcies M. capricolum subsp.capripneumoniae infection, hepatized lesions and necrosis are observed in the lungs. [5] How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Application to Biotechnology

Membrane of M. capricolumcontains factors that are capable of activating cellular macrophage TNFα, which is a tumor necrosis factor. The macrophage could be induced by other bacterial lipopolysaccharide, but this method is limited in application due to the toxicity of bacterial lipopolysaccharide. The relatively stable membrane of M. capricolumis found to be an especially potent and non-lipopolysaccharide activator of macrophage, thus it may have therapeutic value in treating cancer.[11] Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

Various researches of Mycoplasma capricolum are under process. Those projects include antimicrobials effect[6], which is determined by flow cytometry techniques. One of this evaluating experiments is done in Turkey to evaluate the efficacy of danofloxacin (Advocin A180) on goats. The result indicates that this treatment may be able to prevent the spread of Mycoplasma capricolum. [12] Enter summaries of the most recent research here--at least three required Mycoplasma capricolum is also used in experiment of incorporation of nonnatural amino acids into proteins(ie. amber suppression tRNA experiment).Due to the low incorporation efficiency, the application of amber suppression is limited.M. capricolum is proven to be able to contain tRNA with high specificity. [13]

References

[1]Swanepoel R., Efstratiou S, Blackburn NK: "Mycoplasma capricolum associated with arthritis in sheep". 1977 Veternery Record Volume 101,p, 446-447

[2]Rurangirwa, F. R., T. C. Mcguire, N. S. Magnuson, A. Kibor and S. Chema. "Composition of a polysaccharide from mycoplasma (F38) recognized by antibodies from goats with contagious pleuropneumonia Res." The Journal of Veterinary Science 1987 Volume42 p.175-178

[3]Miyata M, Wang L, Fukumura T, "Physical mapping of the Mycoplasma capricolum genome" FEMS microbiology letters, 1991 Apr 15;63(2-3):329-33

[4]Avron and Ruth Gallily;"Mycoplasma stimulates the production of oxidative radicals by murine peritoneal macrophages." Journal of Leukocyte Biology, Vol 57, Issue 2 264-268

[5]E.H. Johnson, D. E. Muirhead and G. J. King;"Ultrastructural Changes in Caprine Lungs Infected with Mycoplasma capricolum Subspecies capripneumonia" Journal of Veterinary Medicine Series B 49 (4), 206–208

[6]Patricia Assunção,Nuno T. Antunes,Ruben S. Rosales,Carlos Poveda,Jose B. Poveda and Hazel M. Davey;"Flow Cytometric Determination of the Effects of Antibacterial Agents on Mycoplasma agalactiae, Mycoplasma putrefaciens,Mycoplasma capricolum subsp. capricolum, and Mycoplasma mycoides subsp. mycoides Large Colony Type ";Antimicrobial Agents and Chemotherapy, August 2006, p. 2845-2849, Vol. 50, No. 8

[7]Elmiro R. Nascimento, Al J. DaMassa, Richard Yamamoto, M. Graça F. Nascimento; "Plasmids in Mycoplasma species isolated from goats and sheeps and their preliminary typing"; Revista de Microbiologia, 1999 30: p.32-36

[8]M Tarshis, M Salman, and S Rottem; "Cholesterol is required for the fusion of single unilamellar vesicles with Mycoplasma capricolum"; Biophysical Journal. 1993 March; 64(3): 709–715

[9]Masaki Q. Fujitaa, Hiroshi Yoshikawab and Naotake Ogasawarab; "Structure of the dnaA and DnaA-box region in the Mycoplasma capricolum chromosome: conservation and variations in the course of evolution";Gene Volume 110, Issue 1, 2 January 1992, p.17-23

[10]Jean Dahl; "Uptake of Fatty Acids by Mycoplasma capricolu"; Journal of Bacteriology, May 1988, p.2022-2026

[11]Steve Caplan, Ruth Gallily, Yechezkel Barenholz;"Characterization and purification of a mycoplasma membrane-derived macrophage-activating factor "; Cancer Immunology, Immunotherapy,Volume 39 p.27-33, Number 1 / January, 1994

[12]U. Ozdemir, G. R. Loria, K. S. Godinho, R. Samson, T. G. Rowan, C. Churchward, R. D. Ayling and R. A. J. Nicholas; "Effect of danofloxacin (Advocin A180) on goats affected with contagious caprine pleuropneumonia";Tropical Animal Health and ProductionVolume 38, Numbers 7-8 / October, 2006 p.533-540

[13]Hikaru Taira, Yohsuke Matsushita, Kenji Kojima and Takahiro Hohsaka ; "Development of amber suppressor tRNAs appropriate for incorporation of nonnatural amino acids "; Nucleic Acids Symposium SeriesNo. 50 Pp. 233-234, 2006