Related Experiment Video
Updated: Jun 10, 2026

Identification of Rare Bacterial Pathogens by 16S rRNA Gene Sequencing and MALDI-TOF MS
Published on: July 11, 2016
Characterization of some bacterial strains isolated from animal clinical materials and identified as Corynebacterium
Lucía Palacios1, Ana Isabel Vela, Kent Molin
1Centro de Vigilancia Sanitaria Veterinaria (VISAVET), Universidad Complutense, 28040 Madrid, Spain.
Abstract:
Eighteen Corynebacterium xerosis strains isolated from different animal clinical specimens were subjected to phenotypic and molecular genetic studies. On the basis of the results of the biochemical characterization, the strains were tentatively identified as C. xerosis. Phylogenetic analysis based on comparative analysis of the sequences of 16S rRNA and rpoB genes revealed that the 18 strains were highly related to C. xerosis, C. amycolatum, C. freneyi, and C. hansenii. There was a good concordance between 16S rRNA and partial rpoB gene sequencing results, although partial rpoB gene sequencing allowed better differentiation of C. xerosis. Alternatively, C. xerosis was also differentiated from C. freneyi and C. amycolatum by restriction fragment length polymorphism analysis of the 16S-23S rRNA gene intergenic spacer region. Phenotypic characterization indicated that besides acid production from D-turanose and 5-ketogluconate, 90% of the strains were able to reduce nitrate. The absence of the fatty acids C(14:0), C(15:0), C(16:1)omega 7c, and C(17:1)omega 8c can also facilitate the differentiation of C. xerosis from closely related species. The results of the present investigation demonstrated that for reliable identification of C. xerosis strains from clinical samples, a combination of phenotypic and molecular-biology-based identification techniques is necessary.
Related Concept Videos
Bacterial Phylum Actinobacteria
Methods of Classification and Identification
Applications of Molecular Taxonomy
Clinical Significance of Antibiotic Resistance
Rapid Identification of Pathogens
Bacterial Phylum Tenericutes

