
The six species of
mycoplasmas which belong to the “mycoides group” (M. mycoides ssp
mycoides SC (MmmSC), M. mycoides ssp mycoides LC
(MmmLC), M. mycoides ssp capri (Mmc), M. capricolum ssp
capricolum (Mcc), M. capricolum ssp capripneumonia
(Mccp), M. sp Group 7 of Leach (Mg7) are all pathogens of
ruminants. Two of these (MmmSC and Mccp) are responsible for diseases
from list A and B of the goose, which have been eradicated in most
developed countries. The others are widely distributed in the world,
and they cause diverse syndromes in ruminants characterized by
mammitis, arthritis, keratitis, pneumonia and septicemia.
Large economic losses occur on affected farms, and although
antibiotics may reduce economic losses, they do not eradicate the
infection.
The comparative study of mycoplasmal genomes from
this “mycoides group” will be very interesting from a fundamental
point of view because each species has a specific tropism, either for
a given species (cattle or goat), or for a specific organ (lung for
MmmSC, mammary gland for MmmLC).
Comparative genomics applied to the complete genomes of the ensemble
of the “mycoides group”, will make it possible to better understand
their phylogeny and to identify the genes implicated in their
pathogenic capacities.
Furthermore, this group is phylogenetically very close to
Spiroplasma citri and S. kunkelii, plant pathogens
for which sequencing is in progress, which will enhance the value of
comparative genomic studies, which is the essential basis for the
developoment of diagnostic techniques.