Draft Genome Sequences of Two Species of “Difficult-to-Identify” Human-Pathogenic Corynebacteria: Implications for Better Identification Tests

Abstract

Non-diphtheriae Corynebacterium species have been increasingly recognized as the causative agents of infections in humans. Differential identification of these bacteria in the clinical microbiology laboratory by the most commonly used biochemical tests is challenging, and normally requires additional molecular methods. Herein, we present the annotated draft genome sequences of two isolates of “difficult-to-identify” human-pathogenic corynebacterial species: C. xerosis and C. minutissimum. The genome sequences of ca. 2.7 Mbp, with a mean number of 2,580 protein encoding genes, were also compared with the publicly available genome sequences of strains of C. amycolatum and C. striatum. These results will aid the exploration of novel biochemical reactions to improve existing identification tests as well as the development of more accurate molecular identification methods through detection of species-specific target genes for isolate's identification or drug susceptibility profiling.

Whole-Genome Sequence of Corynebacterium xerosis Strain GS1, Isolated from Yak in Gansu Province, China

“…Corynebacterium xerosis is a commensal organism present in the skin and mucous membranes of humans (2). The species C. xerosis is also a frequently reported human pathogen, with isolates being identified in cases that include ear infections, brain abscesses, osteomyelitis, and maternal ventriculoperitoneal shunt infections (3, 4). It has also been isolated in pure culture from normally sterile organs of animal clinical specimens.…”

Efficient differentiation of Corynebacterium striatum , Corynebacterium amycolatum and Corynebacterium xerosis clinical isolates by multiplex PCR using novel species-specific primers

“…Herein, we have developed a multiplex PCR method based on species-distinctive genes for accurate identification at the species level of C. striatum, C. amycolatum and C. xerosis. Speciesspecific target genes were detected by whole-genome comparisons between recently sequenced isolates (Pacheco et al, 2015;Mattos-Guaraldi et al, 2015). In brief, comparative genome analyses were performed through the software platforms EDGAR 2.0 (http://edgar.computational.bio) and SEED Viewer (http://pubseed.theseed.org); hypothetical genes were filtered out and the remaining annotated unique genes for each species were further interrogated using NCBI's BlastN searches for definition of PCR targets.…”