This review provides comprehensive information on the identification of c Coryneform bacteria and outlines recent changes in taxonomy and case reports claiming disease associations of coryneformacteria are critically reviewed.
Clinical relevance, phenotypic and genetic identification methods, matrix-assisted laser desorption ionization–time of flight evaluations, and antimicrobial susceptibility testing involving species in the genus Corynebacterium and other medically relevant Gram-positive rods, collectively called coryneforms are described.
The development of a multilocus sequence typing (MLST) scheme for Corynebacterium diphtheriae, the causative agent of the potentially fatal upper respiratory diseasediphtheria, provides a valuable tool for monitoring and characterizing endemic and epidemic C. diphTheriae strains.
The 16S rRNA gene sequencing data demonstrate that the genera Corynebacterium and Turicella are more closely related to the partially acid-fast bacteria and to the genus Mycobacterium than to the other coryneform organisms covered in the chapter.
The characteristics of 72 strains identified as or most closely resembling 14 of these newer, medically relevant Corynebacterium species or taxa described since 1995 are reported, as well as an isolate of Coryne bovis, a rare pathogen for humans.
Six clinical isolates of a hitherto unknown, strictly anaerobic, Gram-negative rod showing fastidious growth were subjected to a polyphasic taxonomic study, including phenotypic, genomic and phylogenetic feature analyses, finding that the novel strains represent a homogeneous group distant from any recognized species in the candidate phylum 'Synergistetes'.
A retrospective analysis of PFGE data uncovered several clusters that might have represented undetected outbreaks, suggesting that comprehensive prospective PFGE analysis coupled with prompt epidemiological investigations might lead to improved outbreak detection and control.
Chemotaxonomic and molecular genetic investigations revealed that the strains of the second cluster unambiguously belonged to the species C. amycolatum, suggesting that most strains reported in the literature as C. xerosis are probably misidentified and correspond to C. Amycolatum.
An outbreak of Legionnaires' disease at a long-term care facility in Ontario, Canada from September to October 2005 resulted in the death of 23 residents and the illness of 112 other people and molecular methods confirmed the outbreak source as a contaminated air conditioning cooling tower.
It is concluded that these strains represent a novel genus and species within the suborder Corynebacterineae for which the name Lawsonella clevelandensis gen. nov., sp.