Isolation and Characterization of Capnocytophaga bilenii sp. nov., a Novel Capnocytophaga Species Detected in a Gingivitis Subject

Abstract

Capnocytophaga species are commensal gliding bacteria that are found in human and animal oral microbiota and are involved in several inflammatory diseases, both in immunocompromised and immunocompetent subjects. This study contributes to increased knowledge of this genus by characterizing a novel species isolated from a dental plaque sample in a male with gingivitis. We investigated morphological and chemotaxonomic characteristics using different growth conditions, temperature, and pH. Cellular fatty acid methyl ester (FAME) analysis was employed with gas chromatography/mass spectrometry (GC/MS). Phylogenetic analysis based on 16S rRNA, orthologous average nucleotide identity (OrthoANI), and digital DNA–DNA hybridization (dDDH) relatedness were performed. The Marseille-Q4570T strain was found to be a facultative aerobic, Gram-negative, elongated, round-tipped bacterium that grew at 25–56 °C and tolerated a pH of 5.5 to 8.5 and an NaCl content ranging from 5 to 15 g/L. The most abundant fatty acid was the branched structure 13-methyl-tetradecanoic acid (76%), followed by hexadecanoic acid (6%) and 3-hydroxy-15-methyl-hexadecanoic acid (4%). A 16S rDNA-based similarity analysis showed that the Marseille-Q4570T strain was closely related to Capnocytophaga leadbetteri strain AHN8855T (97.24% sequence identity). The OrthoANI and dDDH values between these two strains were, respectively, 76.81% and 25.6%. Therefore, we conclude that the Marseille-Q4570T strain represents a novel species of the genus Capnocytophaga, for which the name Capnocytophaga bilenii sp. nov. is proposed (=CSUR Q4570).

Microbiological profile of peri‐implantitis: Analyses of peri‐implant microbiome

“…17,46,47 Capnocytophaga is a commensal Gramnegative facultative taxa detected in the oral cavity, and it has been linked to periodontal diseases. [48][49][50] Capnocytophaga leadbetteri was also identified in higher abundance in periimplant pockets of peri-implantitis in agreement with the finding of this study. 42 Another new Gram-negative species that was identified in a high abundance and was related to periodontitis is Treponema maltophilum.…”

“…All the presented above periimplantitis studies used a clustering approach, which assigns taxa based on similarity (mostly threshold of 97%) into operating taxonomic units (OTUs). [39][40][41][42][43][44][45][46][47][48][49][50][51] This clustering method could introduce sequencing error and increase the microbial community's diversity and richness. 60 To overcome the sequencing error, this study used a denoising algorithm (DADA2) that generates amplicon sequence variants (ASVs) to increase the accuracy of the results, especially for lowabundance sequencing.…”

“…Another species detected in high abundance in peri‐implant pockets of peri‐implantitis is Lactococcus lactis which was previously linked with the inner implant surface of peri‐implantitis, endodontic infections and apical granulomas 17,46,47 . Capnocytophaga is a commensal Gram‐negative facultative taxa detected in the oral cavity, and it has been linked to periodontal diseases 48‐50 . Capnocytophaga leadbetteri was also identified in higher abundance in peri‐implant pockets of peri‐implantitis in agreement with the finding of this study 42 .…”

Capnocytophaga catalasegens sp. nov., isolated from feline oral cavities

“…The dDDH value between C. catalasegens sp. nov. strain KC07084 T and C. stomatis strain H2177 was 23.7 % [29], and that between strain KC07084 T and C. bilenii strain CSUR Q4570 was 21.8 % [28]. We will further investigate the classification of the Capnocytophaga species that inhabit canine and feline oral cavities.…”

“…Recently, provisional novel species of the genus Capnocytophaga , C. stomatis and C. bilenii , were also reported [27, 28]. The dDDH value between C. catalasegens sp.…”