A newly discovered facultative anaerobic strain, designated as LXY-3T, was obtained from a soil sample collected at an industrial site in Guangxi, China, known for heavy metal processing. An investigation including phenotypic, chemotaxonomic, and genomic traits was conducted. Phylogenetic analysis based on 16S rRNA showed that LXY-3T belonged to the genus Paenibacillus. The closest phylogenetic relative of this strain was Paenibacillus anaericanus MH21T with the similarity of 97.03%. Iso-C15:0, antéiso-C15:0, and C16:1 ω7c alcohol were the major cellular fatty acids. The predominant polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), unidentified phospholipids (PL1-PL8), unidentified resistant material (RM1–RM4), and lipids (L1–L3). For genome sequencing, the genomic DNA G+C content of the strain is 51.2 mol%. Comparative genomic analysis revealed that the average nucleotide identity (ANI) values between strain LXY-3T and its closest phylogenetic relatives within the genus Paenibacillus (represented by type strains) were consistently below the 95% species demarcation threshold. Nitrogen fixation gene cluster (nifB, nifE, nifK, nifN, nifV, nifX, nifD, and nifH) was conserved in the strain. Correspondingly, digital DNA–DNA hybridization (dDDH) values remained below the 70% cutoff for species delineation. These genomic metrics provide compelling evidence that strain LXY-3T represents a novel species within the genus Paenibacillus. The type strain LXY-3T (=CGMCC 1.64949T = JCM 37600T) is proposed.
Wu et al. (Tue,) studied this question.