Veillonella nakazawae sp. nov., an anaerobic Gram-negative coccus isolated from the oral cavity of Japanese children

Abstract

Two strains of previously unknown Gram-negative cocci, T1-7T and S6-16, were isolated from the oral cavity of healthy Japanese children. The two strains showed atypical phenotypic characteristics of members of the genus Veillonella , including catalase production. Sequencing of their 16S rRNA genes confirmed that they belong to genus Veillonella . Under anaerobic conditions, the two strains produced acetic acid and propionic acid as metabolic end-products in a trypticase–yeast extract–haemin medium containing 1 % (w/v) glucose, 1 % (w/v) fructose and 1 % (v/v) sodium lactate. Comparative analysis of the 16S rRNA, dnaK, rpoB and gltA gene sequences revealed that the two strains are phylogenetically homogeneous and comprise a distinct, novel lineage within the genus Veillonella . The sequences from the two strains shared the highest similarity, at 99.9, 95.8, 96.9 and 96.7 %, using the partial 16S rRNA, dnaK, rpoB and gltA gene sequences, respectively, with the type strains of the two most closely related species, Veillonella dispar ATCC 17748T and Veillonella infantium JCM 31738T. Furthermore, strain T1-7T shared the highest average nucleotide identity (ANI) value (94.06 %) with type strain of the most closely related species, V. infantium . At the same time, strain T1-7T showed the highest digital DNA–DNA hybridization (dDDH) value (55.5 %) with the type strain of V. infantium . The two strains reported in this study were distinguished from the previously reported species from the genus Veillonella based on catalase production, partial dnaK, rpoB and gltA sequences, average ANI and dDDH values. Based on these observations, the two strains represent a novel species, for which the name Veillonella nakazawae sp. nov. is proposed. The type strain is T1-7T (JCM 33966T=CCUG 74597T).

Complete Genome Sequence of Veillonella nakazawae JCM 33966 T (=CCUG 74597 T ), Isolated from the Oral Cavity of Japanese Children

“…With the addition of the annotated genome sequence of V. nakazawae described here, the genome sequences of 8 species of oral Veillonella are now available to the public. In addition, the results of a genome comparison of V. nakazawae JCM 33966 T (=CCUG 74597 T ) against reported type strains of the genus Veillonella were reported in our recent study ( 5 ). The data obtained will help clarify the anticariogenic mechanisms or functions of Veillonella in future studies.…”

“…At present, 8 species from the genus Veillonella have been isolated from the human oral cavity, and they are called oral Veillonella ( 5 – 11 ). These 8 species have shown lactate consumption ability ( 5 – 11 ). As lactate causes dental caries, it has been suggested that oral Veillonella may be anticariogenic ( 12 ).…”

“…However, the anticariogenic mechanisms or functions of these species have not been clarified. Therefore, to promote the study of the mechanisms underlying the functioning of oral Veillonella , we determined the complete genome sequence of V. nakazawae JCM 33966 T (=CCUG 74597 T ), a V. nakazawae type strain ( 5 ).…”

“…The versions in this paper are the first versions reported. These accession numbers were originally published by Mashima et al ( 5 ).…”

“…Veillonella nakazawae was isolated from the oral cavity of Japanese children and was established as a novel Veillonella species in 2020 (5). At present, 8 species from the genus Veillonella have been isolated from the human oral cavity, and they are called oral Veillonella (5)(6)(7)(8)(9)(10)(11). These 8 species have shown lactate consumption ability (5)(6)(7)(8)(9)(10)(11).…”