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3427Biochemical and chemotaxonomical studies were performed on some streptococci from frozen peas and bovine mastitis in an attempt to clarify their taxonomy. The results of the present and earlier studies indicate the pea and mastitis isolates represent two new species of the genus Streptococcus. The isolates from frozen peas are named Streptococcus plantarum sp. nov. and those from mastitis, Streptococcus garvieae sp. nov. The type strains are NCDO 1869 and NCDO 21 55, respectively.

The phylogenetic interrelationships of members of the genus Carnobacterium and some atypical lactobacilli isolated from diseased salmonid fish were investigated by using reverse transcriptase sequencing of 16s rRNA. The four species Carnobacterium piscicola, Carnobacterium divergens, Carnobacterium gallinarum, and Carnobacterium mobile exhibited a high degree of sequence similarity with each other (ca. 96 to 98%) and formed a phylogenetically coherent group that was quite distinct from all other lactic acid bacteria. The sequence data clearly demonstrated that carnobacteria are phylogenetically closer to the genera Enterococcus and Vagococcus than to members of the genus Lactobacillus. The strains from fish were found to be phylogenetically related to the genus Vagococcus and represent a new species, Vagococcus salmoninarum. The type strain of Vagococcus salmoninarum is strain NCFB 2777.The genus Carnobacterium was proposed by Collins et al. (4) to accommodate the species Lactobacillus piscicola (17) and Lactobacillus divergens (18) and some so-called atypical lactobacilli isolated from poultry meat (24). Currently, four species, Carnobacterium piscicola (type species), Carnobacterium divergens, Carnobacterium gallinarum, and Carnobacterium mobile are recognized in this genus (4). Although these four species form a phenotypically coherent group (4, 9), the separateness of the genus Carnobacterium (in particular its relationship to the genus Lactobacillus) remains unclear. Members of the genus Carnobacterium differ from Lactobacillus species by their inability to grow on acetate medium (4, 9) and by their synthesis of oleic acid (c18:1A9,10) instead of cis-vaccenic acid (c18:1A11,12), which is produced by lactobacilli (4). At present these are the only criteria which distinguish the two genera.Sequencing of 16s rRNA by reverse transcriptase (20, 21) is currently the most rapid and powerful technique for elucidating the natural relationships of microorganisms (26). This method produces long stretches of sequence (ca. 95% of the total sequence), which enables precise phylogenetic relationships to be determined (26). In this study we determined 16s rRNA primary structures for members of the genus Carnobacterium by using reverse transcription in an attempt to clarify the relationship of these organisms to the genus Lactobacillus and other lactic acid bacteria. In addition, the phylogenetic position of two representative strains belonging to a group of atypical lactobacilli isolated from salmonid fish was also determined. MATERIALS AND METHODSCultures and cultivation. The test strains which we used are shown in Table 1. Strains of carnobacteria, enterococci, lactococci, leuconostocs, pediococci, and streptococci and fish isolates OS1-68T (T = type strain) and Rangen 128-81 were grown in YGPB broth (12) at 30°C. Strains OS1-68T and Rangen 128-81 were isolated by R.A. Holt, Oregon Department of Fish and Wildlife; strain OS1-68T was isolated in 1968 from an adult rainbow trout at the Oak Spring Hatchery * Corresponding...

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Carboxyphilic strains which had characteristics commonly attributed to the group D streptococci and especially to Streptococcus bovis were isolated from the ceca of chickens. However, these strains differed from S. bovis in being positive for ribose, melezitose, P-glucuronidase, and alkaline phosphatase, and negative for group D reactions and growth enhancement by C02. These differences were confirmed by deoxyribonucleic acid-deoxyribonucleic acid hybridization tests. The strains form a new species, for which the name Streptococcus c'ecorum is proposed. Strain A60 (=NCDO 2674) is the type strain of this species.During an investigation of the susceptibilities of intestinal bacteria isolated from chickens to antimicrobial agents used in farm animals (G. N . Dutta, D. Vet. Sci. thesis, University of Gent, Gent, Belgium, 1983), a group of carboxyphilic streptococci was found which could not be identified as any known streptococcal species. The strains in this group were able to grow at 45°C and in the presence of 40% bile, two characteristics which are commonly attributed only to the enterococci or group D streptococci. After the tests advocated by Facklam (6) and Sharpe (21) for the separation of fecal streptococci from other streptococci (growth at pH 9.6, in 6.5% NaC1, and at 10 and 45°C) were performed, the strains were tentatively identified as Streptococcus bovis. However, three reactions were in discordance with this identification; the strains failed to react with the Streptococcus group D antisera used, they were able to grow to a limited extent at pH 9.6, and their growth was definitely better in an atmosphere containing 5% C02 than in air.A subsequent biochemical and genetic study showed that these strains should be designated a new species, which is described here. MATERIALS AND METHODSStrains. Strains A2a, A16, A29, A37 through A40, and A60T (T = type strain) were isolated from the ceca of eight chickens from eight farms in Belgium by using Islam medium (12) supplemented with 30 Fg of neomycin per ml and 15 pg of nalidixic acid per ml. The plates were incubated for 48 h in 5% COz in air. S . bovis CCM 5616 was obtained from the Czechoslovak Collection of Microorganisms, Brno. Other reference strains were obtained from the National Collection of Dairy Organisms (NCDO), Shinfield, Reading, England. _____Media and culture incubation. Media were obtained from Oxoid Ltd., Basingstoke, England, unless otherwise stated. Cultures were normally incubated at 37°C.Growth characteristics. Growth on sheep bloodColumbia agar plates was compared after incubation aerobically and in a 5% C 0 2 atmosphere for 16 and 48 h. All of the other tests except the API tests were performed in a 5 to 10% C 0 2 atmosphere.Biochemical reactions. Dextran and levan formation was tested on heart infusion agar supplemented with 5% (wthol) sucrose. Acid production was tested in phenol red broth base (GIBCO, Paisley, Scotland) containing 1% (wthol) carbohydrate. Glycerol fermentation was tested anaerobically on the solidified medium descri...

Lactobacillus pentosus (Fred, Peterson, and Anderson)

Summary The small subunit rRNA sequences of 55 species of the genus Lactobacillus were determined by reverse transcription in an attempt to elucidate their natural interrelationships. Comparative analysis of the sequence data revealed the presence of 3 phylogenetically distinct clusters. Cluster 1 (designated) the L. delbrueckii group) included L. delbrueckii the type species of the genus and 11 other obligately homofermentative species. Cluster 2 (designated the L. casei group) comprised 32 Lactobacillus species and 5 Pediococcus species (including P. damnosus, the type species of the genus). With the exception of 5 obligately homofermentative species (L. animalis, L. ruminis, L. salivarius, L. sharpeae, L. yamanashiensis) most members of cluster 2 were heterofermentative. Cluster 3 (designated the Leuconostoc paramesenteroides group) included the atypical heterofermentative lactobacilli, L. confusus L. kandleri, L. minor, L. viridescens and Leu. paramesenteroides. The sequence data clearly demonstrate that the genus Lactobacillus as presently constituted is phylogenetically very heterogeneous. Further, the rRNA groups identified in the present study do not correspond to the classical division of Lactobacillus into the subgenera Thermobacterium, Streptobacterium and Betabacterium established on the basis of phenotype.