Phenotypic and phylogenetic characterization of some Gemella‐like organisms from human infections: description of Dolosigranulum pigrum gen. nov., sp. nov.

Abstract

A phylogenetic analysis was performed on two previously uncharacterized Gram-positive, catalase-negative bacteria from clinical sources. 16S rRNA sequencing studies revealed the isolates represent a new line of descent within the lactic acid group of bacteria. On the basis of the phylogenetic findings and phenotypic distinctiveness of the organisms, it is proposed that they be classified in a new genus Dolosigranulum, as Dolosigranulum pigrum sp. nov. The type strain of Dolosigranulum pigrum is NCFB 2975.

Catellicoccus marimammalium gen. nov., sp. nov., a novel Gram-positive, catalase-negative, coccus-shaped bacterium from porpoise and grey seal

“…However, the great majority of newly defined genera containing catalase-negative, coccus-shaped organisms have resulted from improved knowledge of the phylogeny of these organisms due to 16S rRNA gene sequencing and the utility of this molecular tool to search for novel phylogenetic diversity (e.g. Aguirre et al, 1993;Collins et al, 1989Collins et al, , 1992Collins et al, , 1997Collins et al, , 1999. Currently over 20 genera of Gram-positive, facultatively anaerobic, catalase-negative cocci are known and it is evident that much novel diversity remains to be described.…”

Allofustis seminis gen. nov., sp. nov., a novel Gram-positive, catalase-negative, rod-shaped bacterium from pig semen

“…1). In terms of sequence similarities, the unknown organism displayed 88?5 % sequence similarity to Dolosigranulum pigrum NCFB 2975 T , a coccus-shaped organism associated with human clinical sources (Aguirre et al, 1993). A comparable level of sequence similarity (88?4 %) was also displayed between the porcine bacterium and some uncultured bacteria (16S rDNA accession numbers AF124034 and AF124041) associated with sheep scab mites (Hogg & Lehane, 1999).…”

Phlyctenular Keratoconjunctivitis Associated withDolosigranulum pigrum

“…The organism has emerged as a potential pathogen in humans and has been identified in a broad spectrum of diseases, including nosocomial pneumonia and 9 and cystic fibrosis pneumonia. 10 Ocular involvement of D. pigrum has been reported in cases of a neurotrophic cornea, 11 blepharitis, 12 keratitis, 13 and bacterial conjunctivitis.…”

“…It was first described in 1993 by Aguirre et al as a lactic acid, gram-positive, catalase-negative organism arranged in pairs and clusters. 11 It was previously misclassified as part of the Gemella species and closely resembles Streptococci viridans on blood agar cultures. It is phenotypically distinguished from other catalasenegative, gram-positive cocci by positive vancomycin susceptibility, pyrrolidonyl arylamidase and leucine aminopeptidase hydrolysis, growth in 6.5% NaCl broth, and esculin hydrolysis.…”