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Related to Mycoplasmas: Mycoplasma genitalium


The smallest prokaryotic microorganisms that are able to grow on cell-free artificial media. Their genome size is also among the smallest recorded in prokaryotes, about 5 × 108 to 109 daltons. The mycoplasmas differ from almost all other prokaryotes in lacking a rigid cell wall and in their incapability to synthesize peptidoglycan, an essential component of the bacterial cell wall.

Taxonomically, the mycoplasmas are assigned to a distinct class, the Mollicutes, containing two orders, Mycoplasmatales and Acholeplasmatales. The distinction between the orders is based primarily on differences in nutritional criteria: members of the Mycoplasmatales require cholesterol or other sterols for growth whereas those of the second order do not. The term mycoplasmas is generally used as the vernacular or trivial name for all members of the class Mollicutes, irrespective of the classification in a particular genus.

The mycoplasmas are almost ubiquitous in nature. Several species are important pathogens of humans, animals and plants, while others constitute part of the normal microbial flora of, for example, the upper respiratory and lower urogenital tracts of humans. Mycoplasma pneumoniae was found to be the cause of cold agglutinin-associated primary atypical pneumonia. This disease is particularly frequent in the 5–15-year age group; it is probably endemic almost all over the world and often reaches epidemic proportions at intervals of 4 to 5 years.

Mycoplasmas are generally highly resistant to benzyl penicillin and other antibiotics which act by interfering with the biosynthesis of peptidoglycan. They are usually susceptible to antibiotics that specifically inhibit protein synthesis in prokaryotes, such as tetracyclines and chloramphenicol. Susceptibility to other antibiotics, such as erythromycin and other macrolides, is variable. See Antibiotic, Bacterial physiology and metabolism, Plant pathology, Pneumonia

References in periodicals archive ?
This approach has successfully been developed for Mycoplasmas pneumoniae (Abele-Horn et al.
3,4,8,9) As previously documented, the relative occurrence of different species of known mycoplasmas in pigeons seems to vary according to the investigated geographic region.
Among 20 different species, Mycoplasma gallisepticum (MG) is one of the avian bacterial pathogen responsible for chronic respiratory disease (CRD).
Most of the epidemiological studies on Mycoplasma infection have been conducted in high-risk populations, such as symptomatic and asymptomatic patients attending STI clinics.
However, the parasite-host relationship in individuals with HIV coinfected by mycoplasmas still presents significant gaps.
A7agar incorporates a direct test for urease that allows the differentiation of urea plasma from the other Mycoplasma tales.
Development and clinical application of an InvaderPlus[R] assay for the detection of genital mycoplasmas.
Besides these new services, ABR offers mycoplasma testing to satisfy USDA 9CFR regulations and also provides an extensive list of other testing services for viruses and bacteria.
In this study two primers (forward and reverse) were previously designed by Pourbakhsh [22] and amplify a 163 bp region of 16S rRNA gene of Mycoplasma genus.
A method for determining utilization of glucose by mycoplasmas.
Mixed infection was observed in this study which may be due to the association of Mycoplasma spp, Ureaplasma spp, and C.
Aliquots of pleural fluid and lung tissue were collected and sent to the laboratory for confirmatory diagnosis which was found to be positive for Mycoplasma on culture.