Genome-based reclassification of Sphingopyxis lutea Chhetri et al. 2023 as a later heterotypic synonym of Sphingopyxis jiangsuensis Gao et al. 2023

Abstract

Sphingopyxis lutea DHUNG17T was compared with Sphingopyxis jiangsuensis XHP0097T to examine the taxonomic relationship between the two type strains. The 16S rRNA gene sequence of S. lutea DHUNG17T shared high similarity (99.9 %) to that of S. jiangsuensis XHP0097T. The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the two strains formed a tight cluster within the genus Sphingopyxis. The average amino acid identity, average nucleotide identity and digital DNA–DNA hybridization values between S. lutea DHUNG17T and S. jiangsuensis XHP0097T were below 99.0, 99.1 and 92.2±1.7 %, respectively, all of which were greater than the species delineation threshold for AAI (95.5 %), ANI (95–96 %) and dDDH (70 %), strongly indicating that the two strains represented a single species. Based on the combined phylogenetic, genomic and phenotypic characterization presented here, we propose Sphingopyxis lutea as a later heterotypic synonym of Sphingopyxis jiangsuensis.