Characterization of a novel Gram-positive, catalase-negative coccus from horses: description of Eremococcus coleocola gen. nov. sp. nov.

Abstract

Two strains of an unknown Gram-positive, catalase-negative, facultatively anaerobic coccus originating from the reproductive tract of horses were characterized by phenotypic and molecular taxonomic methods. Comparative 165 rRNA gene sequencing studies demonstrated that the two strains constitute a new subline within the lactic-acid group of bacteria, close to, but distinct from, Abiotrophia defectiva, Globicatella sanguinis and close relatives. The unknown bacterium was readily distinguished from other described Grampositive, catalase-negative cocci by biochemical tests and electrophoretic analysis of whole-cell proteins. On the basis of phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as €remococcus coleocola gen. nov., sp. nov. The type strain of Eremococcus coleocola is CCUG 38207T.Keywords: Eremococcus coleocola gen. nov., sp. nov., taxonomy, phylogeny, 16srRNA, horseThe Gram-positive, catalase-negative cocci constitute a phenotypically heterogeneous group of organisms within the Clostridium subphylum of the Grampositive bacteria. In the 1986 edition of Bergey's Manual of Systematic Bacteriology, only six genera of Gram-positive, catalase-negative cocci were listed (Sneath et al., 1986). During the past decade, the number of described genera and species of Grampositive, catalase-negative cocci has increased considerably. Some of these new taxa have resulted from the taxonomic reorganization of existing genera, such as Enterococcus and Lactococcus from the genus Streptococcus; Oenococcus and Weissella from the genus Leuconostoc ; and Tetragenococcus from the genus Pediococcus (Collins et al., 1990(Collins et al., ,1993b; Dicks et their recognition has been largely facilitated by the availability of much-improved taxonomic frameworks, which in turn have stemmed from the use of phenotypic and molecular genetic methodologies in concert. Despite this rapid expansion in the number of described taxa, there is a growing awareness that many other genera and species of Gram-positive, catalasenegative cocci remain to be discovered, particularly from human and animal sources. In this study we describe the characteristics of an unknown a-haemolytic coccus isolated from the reproductive tract of two horses. On the basis of the results of a polyphasic taxonomic study, we describe yet another new taxon, Eremococcus coleocola gen. nov., sp. nov., within the Gram-positive, catalase-negative cocci.

Impacts of Seasonal Housing and Teat Preparation on Raw Milk Microbiota: a High-Throughput Sequencing Study

“…While relatively little is known about the uncultured Corynebacteriales, the cultured equivalent contains species known to cause mastitis (19), as well as other species that are found on the surfaces of surface-ripened cheese (20). Similarly, the other genus noted, Eremococcus, has not been well characterized, although a typed strain does exist, having been isolated from the vaginal discharge of a thoroughbred horse (21). The proportions of the Gram-negative genus Prevotella, which is typically gut associated, were also higher in indoor samples, while, for the outdoor samples, the Gram-negative genera Pseudomonas and Acinetobacter, as well as the Gram-positive genus Lactococcus, were among the more dominant organisms.…”

Globicatella sulfidifaciens sp. nov., isolated from purulent infections in domestic animals.

“…Other characteristics differentiating the two Globicatella species are listed in Table 2. The differential scheme given by Collins et al (1999) can be useful for differentiating the Globicatella strains from other recently described phylogenetically related genera. The reactions listed in this table, which may be of use with respect to G. sanguinis, are not, however, entirely applicable to G. sulfidifaciens.…”

“…sulfidifaciens G. sanguinis* H # S production (Kligler's iron agar) This table is based on the results of Collins et al (1999) and our results obtained with the four collection strains used in this study for comparative purposes.…”

“…Phenotypically, the strains showed some similarity to Streptococcus uberis and the ' bovis ' and ' viridans ' streptococcal groups, as well as the aerococci. Later studies demonstrated that the genus is phylogenetically most closely related to the recently described Emerococcus genus, to Ignavigranum, Facklamia and Abiotrophia, and to the well-established genus Aerococcus (Collins et al, 1999).…”

Bacterial infections of the equine genital tract

“…Individual confirmations of fastidious bacteria such as Eremococcus coleocola in the equine genital tract support the fact that our present-day knowledge on the equine genital flora is limited indeed to the bacteria easily accessible in clinical bacteriology. (Collins et al 1999, Rota et al 2011. A detailed analysis of the equine genital microbiome may enhance our understanding of the normal composition of the genital flora as well as dysbiotic shifts during the pathogenesis of bacterial endometritis.…”