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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Mesomycoplasma hyopneumoniae
Etymology: Genus name: between other mycoplasmas (fungus shaped).
Species epithet: from pneumonia of a pig.
Significance:  [Very important]   
Alternative Species Name(s):Mycoplasma hyopneumoniae
Type Strain: J = ATCC 25934 = NCTC 10110.
Macromorphology (smell):
Forms small and atypical colonies, which lack a clearly defined nipple (no "fried egg appearance") and should be observed in a microscope.
Micromorphology: Non-motile, very small small and pleomorphic
Gram +/Gram -:G-, but is normally not gram stained because the cells will then be fragmented.
Metabolism: Facultatively anaerobic. M. hyopneumoniae is a glucose fermenter, which lowers the pH in the growth medium.
Spec. Char.: Lacks a cell wall.
Disease:Porcine enzootic pneumonia or enzootic pneumonia in pigs (EPP) or swine enzootic pneumonia (SEP).
HostsDiseaseClinical picture
PigPorcine enzootic pneumonia or enzootic pneumonia in pigs (EPP) or swine enzootic pneumonia (SEP).Coughing, poor growth rate and sometimes respiratory distress.
Genome Sequence:
Acc-noStrainSize (bp)Genome
NC_007295 0 897 405 1c + 0 

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AE017243 JT 1 537 

About 15 species have been described within the genus Mesomycoplasma. Mesomycoplasma hyopneumoniae is closely related to M. ovipneumoniae, M. dispar as well as M. flocculare.

Note that the letter M in the phylogenetic tree (Fig. 230:1) can mean Mycoplasma, Mesomycoplasma, Metamycoplasma, Mycoplasmoides or Mycoplasmopsis.

Comment:Based on whole genome sequencing, the taxonomy of mycoplasmas has recently undergone a comprehensive revision. The new taxonomy has now been introduced in VetBact, but it will still be possible to search for the alternative species names. Read more about the revised taxonomy of the mollicutes under the Term list of VetBact and see reference 164 below.
Reference(s): No. 52, 164, 170


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