Identification of actinomyces, propionibacteria, lactobacilli and bifidobacteria by amplified 16S rDNA restriction analysis

Amplified 16S rDNA restriction analysis (ARDRA) with HaeIII and HpaII was applied to 37 reference strains, 179 human clinical and four veterinary isolates of Propionibacterium, Lactobacillus and Bifidobacterium and some other anaerobic, non-sporing, Gram-positive bacilli. Results were compared with those obtained by ARDRA for reference strains (26) and clinical isolates (469) of Actinomyces spp. Reference strains were clearly differentiated to species level. Clinical isolates of Propionibacterium and Lactobacillus were identified with confidence to species level. Bifidobacterium spp. were identified in ARDRA with confidence to genus, but anomalies in species level identification of some reference strains and clinical isolates may reflect unreliable identification in conventional tests. Isolates of Arcanobacterium spp., Actinobaculum schaalii, Eggerthella lenta, some Eubacterium spp., Gardnerella vaginalis, Mobiluncus spp., Atopobium vaginae, Abiotrophia defectiva, Streptococcus mutans, Streptococcus intermedius and Clostridium sp. were clearly differentiated in ARDRA. ARDRA is a simple, rapid, and highly discriminatory method for identification of anaerobic, non-sporing, Gram-positive bacilli. (C) 2001 Academic Press.