The techniques of identification of Corynebacterium non diphtheriae
The proper identification of Corynebacterium non diphtheriae is complicated by their wide species variety, variable biochemical activity, large spectrum of diseases at which they are isolated and also by their presence in normal human micro-flora. The bacteriological methodis a traditional basis for identification ofcorynebacteria though long (7-14 days), produces ambiguous results at cultivation of lipophilic and biochemically variable species. For final identification of nondescript species of Corynebacterium non diphtheriae it is recommended to carry out molecular genetic study using golden standard - sequencing on 16S pRNA (DNA), genes rpoB and PLD.In case of receiving of ambiguous responses of sequencing on 16S pRNA precise identification is achieved by sequencing of secondary gene rpoB that permits discovering unique differences in sequences of genomes in different species of corynebacteria (presence ofgenes of virulence; absence of cluster of genes responsible for production of number of saccharolytic enzymes; presence of genes coding synthesis of particular pigments, etc.). The mass-spectrometric analysis (MALDI-ToF-MS) applied for screening identification of Corynebacterium, is simple in implementation, though requires further development for more accurate differentiation of closely-related species. The poly-phase approach to identification of Corynebacterium non diphtheriae is needed which is to include chemotaxonomic, phenotypic, genotypic information requiredfor reliable description of new clinically significant species of corynebacteria.