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Contribution to the taxonomy of haemolytic corynebacteria
Insights
This study differentiates hemolytic corynebacteria from streptococci using biochemical markers. A distinct subgroup of aerobic hemolytic corynebacteria was identified, differing from human and animal strains.
Area of Science:
- Microbiology
- Bacterial Taxonomy
- Biochemistry
Background:
- Corynebacterium haemolyticum and Corynebacterium pyogenes bovis are hemolytic bacteria with unclear taxonomic relationships.
- Distinguishing these from typical corynebacteria and streptococci is crucial for accurate classification.
Purpose of the Study:
- To assess taxonomic relationships among human and animal hemolytic corynebacteria, typical corynebacteria, and streptococci.
- To identify unique biochemical profiles for bacterial differentiation.
Main Methods:
- Analysis of DNA guanine-plus-cytosine (G+C) content.
- Assessment of the cytochrome system presence.
- Gas chromatography of fatty acid composition in free lipids.
- Identification of carboxylic acids produced during fermentation.
Main Results:
- Streptococci were biochemically distinct from all studied corynebacteria.
- A subgroup of aerobic hemolytic corynebacteria was identified.
- This subgroup possessed a complete cytochrome system, produced propionic acid, and had a unique fatty acid profile.
Conclusions:
- Biochemical analyses effectively differentiate streptococci from corynebacteria.
- Aerobic hemolytic corynebacteria represent a distinct taxonomic group separate from human and animal strains.
Abstract:
In an attempt to assess the taxonomic relationships among human (Corynebacterium haemolyticum), animal (Corynebacterium pyogenes bovis) haemolytic corynebacteria, typical corynebacteria (Corynebacterium diphteriae mitis, C. ovis, C. ulcerans) and group A and G streptococci, a number of biochemical parameters were established: the DNA content of G + C, the presence of the cytochrome system, composition of fatty acids in free lipids and production of carboxylic acids as end products of fermentation. It was found that according to the above criteria, streptococci differed significantly from the corynebacteria studied. In addition, it was possible to differentiate a subgroup of typically aerobic haemolytic corynebacteria (different from both human and animal corynebacteria), possessing a complete cytochrome system, producing propionic acid and having a different composition of fatty acids.