Luteococcus sanguinis sp. nov., isolated from human blood.

An unusual catalase-positive, Gram-positive, coccus-shaped bacterium that originated from a human blood specimen was subjected to a polyphasic taxonomic study. Cell-wall murein and lipid composition analyses indicated that the unknown isolate was a member of the genus Luteococcus. The results of comparative 16S rRNA gene sequence analysis were consistent with chemotaxonomic findings and showed that the unidentified bacterium represents a hitherto unknown sublineage within the genus Luteococcus that is closely related to, but distinct from, Luteococcus japonicus. On the basis of both phenotypic and phylogenetic evidence, it is proposed that the unknown bacterium from human blood should be classified as Luteococcus sanguinis sp. nov., with the type strain CCUG 33897(T) (=CIP 107216(T)).

Actinomyces oricola sp. nov., from a human dental abscess.

A previously undescribed Actinomyces-like bacterium was isolated from a human dental abscess. Based on its cellular morphology and the results of biochemical testing the organism was tentatively identified as a member of the genus Actinomyces, but it did not correspond to any currently recognized species of this genus. Comparative 16S rRNA gene sequencing studies showed the bacterium represents a hitherto unknown subline within the genus Actinomyces, clustering within a group of species, which includes Actinomyces bovis, the type species of the genus. Based on biochemical and molecular phylogenetic evidence, it is proposed that the unknown organism recovered from a dental abscess be classified as a new species, Actinomyces oricola sp. nov. The type strain of Actinomyces oricola is R5292(T) (=CCUG 46090(T)=CIP 107639(T)).

Corynebacterium atypicum sp. nov., from a human clinical source, does not contain corynomycolic acids.

An unusual gram-positive, facultatively anaerobic, catalase-positive, diphtheroid-shaped organism originating from an unknown human clinical source was characterized by biochemical, molecular chemical and molecular phylogenetic methods. Based on its morphological and biochemical characteristics and the presence of a murein based on meso-diaminopimelic acid, the unidentified organism was tentatively assigned to the genus Corynebacterium. However, the unknown organism was found to lack the distinctive, short-chain corynomycolic acids that are considered to be characteristic of this genus. Despite the absence of these characteristic lipids, comparative 16S rRNA gene sequencing showed that the unknown bacterium was phylogenetically a member of the genus Corynebacterium and was distinct from all currently known species. Based on both phenotypic and 16S rRNA sequence considerations, it is proposed that the unknown organism be classified as a novel species, Corynebacterium atypicum sp. nov. The type strain of C. atypicum is strain R2070T (=CCUG 45804T=CIP 107431T).

Actinobaculum urinale sp. nov., from human urine.

A hitherto undescribed Actinomyces-like bacterium was isolated from human urine. Based on its biochemical characteristics, the unidentified bacterium did not correspond to any currently described Actinomyces species or related taxa. Comparative 16S rRNA gene sequencing showed that the unknown bacterium exhibits a specific phylogenetic association with the genus Actinobaculum, but a sequence divergence of > 5% from the two currently recognized members of this genus, Actinobaculum schaalii and Actinobaculum suis, demonstrates that it represents a distinct species. Based on both phenotypic and 16S rRNA gene sequence considerations, it is proposed that the unknown bacterium from urine should be classified as a novel species, Actinobaculum urinale sp. nov. The type strain of Actinobaculum urinale is CCUG 46093(T) (= CIP 107424(T)).

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

An unknown Gram-positive, catalase-negative, facultatively anaerobic, non-spore-forming, rod-shaped bacterium originating from semen of a pig was characterized using phenotypic, molecular chemical and molecular phylogenetic methods. Chemical studies revealed the presence of a directly cross-linked cell wall murein based on L-lysine and a DNA G + C content of 39 mol%. Comparative 16S rRNA gene sequencing showed that the unidentified rod-shaped organism formed a hitherto unknown subline related, albeit loosely, to Alkalibacterium olivapovliticus, Alloiococcus otitis, Dolosigranulum pigrum and related organisms, in the low-G + C-content Gram-positive bacteria. However, sequence divergence values of > 11% from these recognized taxa clearly indicated that the novel bacterium represents a separate genus. Based on phenotypic and phylogenetic considerations, it is proposed that the unknown bacterium from pig semen be classified as a new genus and species, Allofustis seminis gen. nov., sp. nov. The type strain is strain 01-570-1(T) (= CCUG 45438(T) = CIP 107425(T)).

Characterization of some actinomyces-like isolates from human clinical sources: description of Varibaculum cambriensis gen nov, sp nov.

Fifteen strains of an anaerobic, catalase-negative, gram-positive diphtheroid-shaped bacterium recovered from human sources were characterized by phenotypic and molecular chemical and molecular genetic methods. The unidentified bacterium showed some resemblance to Actinomyces species and related taxa, but biochemical testing, polyacrylamide gel electrophoresis analysis of whole-cell proteins, and amplified 16S ribosomal DNA restriction analysis indicated the strains were distinct from all currently named Actinomyces species and related taxa. Comparative 16S rRNA gene sequencing studies showed that the bacterium represents a hitherto-unknown phylogenetic line that is related to but distinct from Actinomyces, Actinobaculum, Arcanobacterium, and Mobiluncus: We propose, on the basis of phenotypic and phylogenetic evidence, that the unknown bacterium from human clinical specimens should be classified as a new genus and species, Varibaculum cambriensis gen. nov., sp. nov. The type strain of Varibaculum cambriensis sp. nov. is CCUG 44998(T) = CIP 107344(T).

Streptococcus gallinaceus sp. nov., from chickens.

Three isolates of an unknown Gram-positive, catalase-negative, chain-forming, coccus-shaped organism isolated from an outbreak of septicaemia in a flock of adult broiler parents were characterized by phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing studies demonstrated that the bacterium represents a new subline within the genus Streptococcus, related to, albeit distinct from, Streptococcus acidominimus, Streptococcus ovis, Streptococcus suis and close relatives. The unknown bacterium was readily distinguished from all recognized streptococcal species by biochemical tests. Based on phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium from chickens be classified as Streptococcus gallinaceus sp. nov. The type strain is CCUG 42692T (= CIP 107087T).

Isobaculum melis gen. nov., sp. nov., a Carnobacterium-like organism isolated from the intestine of a badger.

Phenotypic and phylogenetic studies were performed on a hitherto undescribed facultatively anaerobic, catalase-negative, gram-positive rod-shaped organism, strain M577-94T, isolated from the small intestine of a dead badger. It resembled carnobacteria in terms of its long-chain cellular fatty acid composition, but differed markedly from the latter in possessing a cell-wall murein based on L-lysine (type L-Lys-L-Thr-Gly). Comparative 16S rRNA gene sequencing showed that the unknown bacterium represents a new line closely related to, albeit distinct from, the genera Carnobacterium and Desemzia. On the basis of phylogenetic and phenotypic evidence, it is proposed that strain M577-94T be classified as Isobaculum melis gen. nov., sp. nov. The type strain of Isobaculum melis is CCUG 37660T (= DSM 13760T).