Biochemical and serological characterization of mycoplasma strains isolated from the genital tracts of humans in Nigeria

Abstract

Fifty-five (55) Mycoplasma strains isolated from the genital tracts of humans were biochemically characterized using various biochemical tests and also serologically identified by growth inhibition technique using 5 mycoplasma antisera namely M. hominis PG21; M. genitalium G37; M. penetrans GTU54 and 2 strains of M. fermentans PG18 (HRC 6-62-S-170 and M B713-501 -069). Biochemically, 43 (78.2%) strains were identified as Mycoplasma hominis, 8 (14. 5 %) strains as M. fermentans and 4 (7.3%) as M. penetrans. The M. hominis strains hydrolyzed only arginine while the M. fermentans and M. penetrans strains in addition to arginine hydrolysis also broke down glucose fermentatively and oxidatively. The M. fermentans strains showed varying reactions to phosphatase activity and to the reduction of tetrazolium chloride. Serologically, 4 (7.3%) mycoplasma strains were confirmed as M. penetrans GTU54 and of the 8 M.fermentans strains, 4 (7.3%) were identified as M. fermentans PG18 serotype HRC 6-62-S-170 and the other 4 (7.3%) as M. fermentans PG18 serotype MB 713-501-069. Only 13 (30.2%) of the 43 M.hominis strains were identified as M hominis serotype PG21. None was identified as M.genitalium. The heterogeneity of the mycoplasma strains especially M. hominis was observed in this study and the need for the use of multiple antisera in growth inhibition test is hereby supported.