Isolation of Hymenobacter weizhouensis sp. nov. and Hymenobacter latericus sp. nov., two novel species belonging to the genus Hymenobacter, from the soil of Weizhou Island

Two bacterial strains, YIM 151858-1^T and YIM 151500-1^T, were isolated from soil samples collected on Weizhou Island, Beibu Gulf, South China Sea, China. Both strains were aerobic, Gram-negative, non-flagellated and rod-shaped bacteria. Phylogenetic analyses based on the 16S rRNA gene sequences showed that both strains belonged to the genus <i>Hymenobacter</i> of the family <i>Hymenobacteraceae</i>. Strains YIM 151858-1^T and YIM 151500-1^T exhibited 16S rRNA gene sequence similarities of 96.04% and 95.29% to <i>Hymenobacter deserti</i> and <i>Hymenobacter rubripertinctus</i>, respectively. In strain YIM 151858-1^T, the major cellular fatty acids (>10%) were iso-C_{15 : 0}, summed feature 4 (iso-C_{17 : 1} I and/or anteiso-C_{17 : 1} B) and iso-C_{17 : 0} 3-OH, whereas the detected polar lipids included phosphatidylethanolamine (PE), unidentified aminophospholipids (APL), unidentified phospholipids and unidentified lipid (L). In strain YIM 151500-1^T, the major cellular fatty acids (>10%) were iso-C_{15 : 0}, summed feature 4 (iso-C_{17 : 1} I and/or anteiso-C_{17 : 1} B) and anteiso-C_{15 : 0}. The detected polar lipids included unidentified aminolipids, PE, APL and L. The predominant isoprenoid quinone in both strains was MK-7. Based on their genome sequences, the G+C content of both strains YIM 151858-1^T and YIM 151500-1^T was 61.5 mol%. Compared with the most closely related species <i>H. deserti</i> ZLB-3^T and <i>H. rubripertinctus</i> KCTC 62163^T, the strains YIM 151858-1^T and YIM 151500-1^T had 75.4% average nucleotide identity, 68.8% average amino acid identity and 21% digital DNA-DNA hybridization value average, which were below the thresholds for delineation of the two novel species. Based on the results of the polyphasic taxonomy, we propose that strains YIM 151858-1^T and YIM151500-1^T represent novel species, for which we propose the names <i>Hymenobacter latericus</i> sp. nov. (type strain YIM 151858-1^T=MCCC 1K8320=KCTC 92732) and <i>Hymenobacter weizhouensis</i> sp. nov. (type strain YIM 151500-1^T=MCCC 1K08054=KCTC 92531) within the genus <i>Hymenobacter</i>.