Isolation and Characterization of Kingella bonacorsii sp. nov., A Novel Kingella Species Detected in a Stable Periodontitis Subject

Abstract

Members of the genus Kingella are mostly commensals of the oral cavity, but some of them are involved in invasive infections, especially in young children. This study provides new knowledge on the diversity of this genus by describing a novel species of Kingella isolated from a dental plaque sample from a 51-year-old man with a history of periodontitis. Morphological and chemotaxonomic characteristic were investigated using different growth conditions, pH and temperature. Cellular fatty acid methyl ester (FAME) analysis was performed by 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 also performed. Strain Marseille-Q4569T was found to be a facultative aerobic, nonmotile and non-spore-forming rod-shaped bacterium that grows at 28–41.5 °C (optimum 37 °C), pH 5.5–8.5 (optimum pH 7.5) and 5–15 g/L of NaCl. The major fatty acids were Hexadecanoic acid (32.7%), 11-Octadecenoic acid (26.1 %) and 9-Hexadecenoic acid (21.3 %). Despite high 16S rRNA gene sequence similarity (98.72%) between strain Marseille-Q4569T and Kingella oralis strain UB-38T, the degree of OrthoANI was at the limit of the cutoff (95.83%), and the degree of dDDH was lower (63.6%) than thresholds used to delineate prokaryotic species. Therefore, it is proposed that strain Marseille-Q4569T represents a novel species of the genus Kingella, for which the name Kingella bonacorsii sp. nov. is proposed (=CSUR Q4569).

Evolution of longitudinal division in multicellular bacteria of the Neisseriaceae family

“…In the absence of electron microscopy images, species' morphology was defined as rod-shaped based on the reference strain describe in refs. 94 for K. negevensis 95 , for K. bonacorsii 96 , for K. denitrificans 97 , for E. longiqua and E. haliae 98 , for Crenobacter luteus 99 , for C. cavernae 100 , for C. sedimenti 101 , for C. intestine.…”

Phylogenomic analysis of the understudiedNeisseriaceaespecies reveals a poly- and paraphyleticKingellagenus

“…bonacorsii [4]. This isolate was recovered from a gingival sample, and the authors report a 16S rRNA similarity of 98.7%, ANI of 95.83%, and dDDH of 63.6% relative to K. oralis UB-38, as well as non-identification by MALDI-TOF mass-spectrometry [4].…”

“…The ANI scores confirm the majority of the proposed species classifications with one exception. Recently, an unclassified Kingella isolate was proposed to be a new species and was named K. bonacorsii [4]. This isolate was recovered from a gingival sample, and the authors report a 16S rRNA similarity of 98.7%, ANI of 95.83%, and dDDH of 63.6% relative to K. oralis UB-38, as well as non-identification by MALDI-TOF mass-spectrometry [4].…”

“…Recently, an unclassified Kingella isolate was proposed to be a new species and was named K. bonacorsii [4]. This isolate was recovered from a gingival sample, and the authors report a 16S rRNA similarity of 98.7%, ANI of 95.83%, and dDDH of 63.6% relative to K. oralis UB-38, as well as non-identification by MALDI-TOF mass-spectrometry [4]. We replicated each of the genomic calculations reported, as well as additional dDDH calculations using alternative formulae (Tables 1 and 4) [28, 36].…”

“…The Kingella genus includes five taxa: K. potus, K. oralis, K. denitrificans, K. negevensis, and K. kingae (21)(22)(23)(24)(25)(26)(27). Recently, two novel species have been proposed, namely K. bonacorsii and K. pumchi (28,29). All of the Kingella species are typically associated with the oral or oropharyngeal microbiome, a common niche for other Neisseriaceae.…”