A preliminary report on characterization and identification of non tuberculous mycobacteria (NTM) on the basis of biochemical tests and protein / isoenzyme electrophoretic patterns.

ABSTRACT

PURPOSE: To assess the usefulness of protein electrophorograms and protein zymodemes in the identification and characterization of non tuberculous mycobacteria (NTM). METHODS: Cell free extracts (CFEs) from 22 mycobacterial isolates belonging to slow growing and other clinically relevant species were included in the study. The strains isolated from the environment were identified on the basis of their standard biochemical tests; pigmentation and growth characters. The CFEs were electrophoresed and stained for proteins and esterases. RESULTS: Most of the isolates identified on the basis of biochemical tests exhibited characteristic protein and esterase pattern for M.scrofulaceum, M.avium and M.xenopi. Others showed variations in their proteins and esterase pattern though they were identified as M.scrofulaceum, M.avium and M.xenopi. CONCLUSIONS: Based on these studies it appears that because of variability in the protein and isoenzyme patterns of NTM, it may be advisable to use them along with biochemical tests and other tests for identifying and characterizing the different mycobacterial species belonging to slow growers.