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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Mesomycoplasma dispar
Etymology: Genus name: between other mycoplasmas (fungus shaped).
Species epithet: different.
Significance:  [Of minor importance]   
Alternative Species Name(s):Mycoplasma dispar
Type Strain: 462/2 = ATCC 27140 = NTCC 10125
Macromorphology (smell): Forms small and atypical colonies, which are not umbonated (no "fried egg appearance") and should be observed in a microscope.
Micromorphology: The small cells are coccoid or short filamentous.
Gram +/Gram -:G-, but is normally not gram stained because the cells will then be fragmented.
Metabolism: Facultatively anaerobic. M. dispar is a glucose fermenter, which lowers the pH in the growth medium.
Spec. Char.:
Disease:Pneumonia and sometimes mastitis.
HostsDiseaseClinical picture
Cattle (calves)Pneumonia (calf pneumonia)Peribronchiolar lymphoid hyperplasia and purulent bronchiolitis
CattleMastitisReduced milk production
Virulence Factors: Can produce hydrogen peroxide (H2O2) and biofilm.
Genome Sequence:
Acc-noStrainSize (bp)GenomeRef.
CP024161 GS01 1 090 351  Nr 169

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AF412979 462/2T 1475  

About 15 species have been described within the genus Mesomycoplasma. Mesomycoplasma dispar is closely related to M. ovipneumoniae, M. hyopneumoniae 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 also reference 164 below.
Reference(s): No. 164, 168


New names of taxa within the classification category phylum

During October 2021, an article was published by A. Oren och G.M. Garrity, in which new names are proposed for a number of taxa within the classification category phylum. This has resulted in many discussions in social media about whether it was really necessary to make these changes, which have created confusion among microbiologists and other professionals who come into contact with bacteriology.

Published 2022-09-28. Read more...

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