RRC ID 88856
著者 Wang Y, You H, Kong YH, Sun C, Wu LH, Kim SG, Lee JS, Xu L, Xu XW.
タイトル Genomic-based taxonomic classification of the order Sphingomonadales.
ジャーナル Int J Syst Evol Microbiol
Abstract The order Sphingomonadales strains are globally distributed in various biomes and are renowned for their biodegradable and biosynthesis capabilities. At present, it consists of 4 families and 49 genera making it the third largest order within the class Alphaproteobacteria. However, their taxonomy remains complex, especially due to polyphyly in the family Sphingomonadaceae. In this study, we collected 429 Sphingomonadales type strain genomes, reconstructed robust phylogenomic relationships, and proposed delineation thresholds at the genus and family levels based on average amino acid identities (AAI) and evolutionary distances (ED). Based on the maximum-likelihood and Bayesian phylogenomic trees reconstructed by two molecular sets determined by orthologous sequence identity and the Genome Taxonomy Database, the consensus degree values were all higher than 90%, revealing that those phylogenomic trees had similar topological structures. By confirming monophyletic taxa and determining stable nodes, we reclassified the order Sphingomonadales into thirteen families including nine novel ones. AAI calculations indicated that the average intra-family AAI values ranged from 0.62 to 0.84, while inter-family ones were 0.51 to 0.60. ED summaries demonstrated that the average and median intra-family ED values were 0.16 to 0.57, and inter-family ones ranged from 0.50 to 1.22. Comparisons of AAI and ED values calculated by using genomic and phylogenetic analyses supported that those 13 families were significantly separated with p values < 2.2×10-16. Thus, it was speculated that the AAI and ED thresholds for distinguishing different families were <0.6 and >0.5, respectively. Additionally, we reclassified 163 species into new genera with their phylogenetic topologies, according to the previous genus AAI and ED boundaries of 0.7 and 0.4. Our study is the first genomic-based study of the order Sphingomonadales and will promote further insights into the evolution of this order.
巻・号 75(5)
公開日 2025-5-1
DOI 10.1099/ijsem.0.006769
PMID 40372931
PMC PMC12210278
MeSH Bayes Theorem DNA, Bacterial / genetics Evolution, Molecular Genome, Bacterial* Genomics Likelihood Functions Phylogeny* RNA, Ribosomal, 16S / genetics Sequence Analysis, DNA Sphingomonadaceae* / classification Sphingomonadaceae* / genetics
リソース情報
一般微生物 JCM18555 JCM18551 JCM18554