Evaluation of isoenzyme patterns for identification of pathogenic poultry Mycoplasmas

Electrophoretic analysis of isoenzymes in 8 enzymatic systems were used for differentiation of 4 isolates of chicken Mycoplasmas including two strains of M. gallisepticum, one strain of M. gallinarum and one unknown isolate in comparison with a vaccinal strain of M. agalactiae that basically is a pathogen in small ruminants. The enzymatic systems were lactate dehydrogenase (LDH), glucose dehydrogenase (GlDH), glucose 6 phosphate dehydrogenase (G6PD), galactose dehydrogenase (GalDH), 6 phosphogluconate dehydrogenase (6PGDH), malic enzyme (ME), glucose phosphate isomerase (GPI) and alkaline phosphatase (AP). The number of isoenzyme patterns obtained for LDH, GlDH, G6PD, GalDH, 6PGDH, ME, GPI and AP enzymatic systems were 2, 3, 2, 4, 2, 3, 3 and 0, respectively. Except AP enzyme system which is not active in Mycoplasma species, it is concluded that isoenzyme pattern of 7 other studied enzymatic systems, could differentiate between chicken Mycoplasmas and the small ruminant’s strain. Based on the isoenzyme patterns of GalDH system, 2 strains of M. gallisepticum were differentiated from M. gallinarum and the unknown isolate. Isoenzyme patterns of ME system was able to differentiate M. gallinarum from the other chicken isolates. The isoenzyme patterns of GPI system were different for the two strains of M. gallisepticum. The isoenzyme patterns of GalDH, GPI and ME systems, showed that the unknown strain of chicken Mycoplasma is a strain of M. gallisepticum and it is closely related to one of the known M. gallisepticum isolates.