mycoplasma

/muy'koh plaz"meuh/, n.

any of numerous parasitic microorganisms of the class Mollicutes, comprising the smallest self-reproducing prokaryotes, lacking a true cell wall and able to survive without oxygen: a common cause of pneumonia and urinary tract infections.

[1950-55; < NL; see MYCO-, PLASMA]

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Any of the bacteria that make up the genus Mycoplasma.

They are among the smallest of bacterial organisms. The cell varies from a spherical or pear shape to that of a slender branched filament. Mycoplasma species are gram-negative (see gram stain) and do not require oxygen. They are colonial microorganisms that lack cell walls. They are parasites of joints and the mucous membranes lining the respiratory, genital, or digestive tracts of cud-chewing animals, carnivores, rodents, and humans. Toxic by-products excreted by the bacteria accumulate in the host's tissues, causing damage. One species causes a widespread but rarely fatal pneumonia in humans.

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▪ bacterium genus

      any bacterium in the genus Mycoplasma. The name mycoplasma has also been used to denote any species in the class mollicutes or any genus in the order Mycoplasmatales.

      Mycoplasmas are among the smallest of bacterial organisms. The cell varies from a spherical or pear shape (0.3 to 0.8 micrometres [0.0000117 to 0.0000312 inch]) to that of a slender branched filament (up to 150 micrometres [0.00585 inch]). Mycoplasma species are mostly facultatively anaerobic, colonial microorganisms that lack cell walls. Mycoplasma species are parasites of joints and the mucous membranes lining the respiratory, genital, or digestive tracts of ruminants, carnivores, rodents, and humans. Toxic byproducts excreted by the bacterium accumulate in the host's tissues, causing damage. M. pneumoniae causes a widespread but rarely fatal pneumonia in humans. Mycoplasma infection may also trigger a serious immune reaction in the host.

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