Bruguierivorax albus gen. nov. sp. nov. Isolated from Mangrove Sediment and Proposal of Bruguierivoracaceae fam. nov

Abstract

A novel Gram-negative, motile, aerobic rod-shaped bacterium designated BGMRC 2031T was isolated from mangrove sediment collected from Guangxi Province, China. Optimal growth occurred at 28 °C and pH 7.0–8.0 in the presence of 1% (w/v) NaCl. Alignment based on 16S rRNA gene sequences indicated that strain BGMRC 2031T is most closely related to Sodalis praecaptivus HS1T (95.6%, sequence similarity), followed by Biostraticola tofi DSM 19580T (95.5%), Sodalis glossinidius DSM 16929T (95.4%), and Brenneria goodwinii FRB141T (94.9%) sequence similarity. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain BGMRC 2031T formed a distinct branch in a robust cluster and revealed that strain BGMRC 2031T, genera Biostraticola and Sodalis, formed a novel family-level clade in the order Enterobacterales. The novel strain showed an average nucleotide similarity of 74.7%, 74.2%, and 73.1% for S. praecaptivus HS1T, S. glossinidius DSM 16929T, and B. tofi DSM 19580T, respectively. The genomes of the BGMRC 2031T shared the presence of a riboflavin synthesis gene cluster. The menaquinones of strain BGMRC 2031T were MK-8 and Q-8, which were similar to those of genus Biostraticola. The major fatty acids (> 10%) were C16:0 (19.9%), summed feature 2 (iso-C16:1 and/or C14:0 3-OH, 18.10%), summed feature 3 (C16:1ω7c and/or C16:1ω6c, 15.3%), C12:0 (13.9%), C17:0 cyclo (11.4%), and C14:0 (10.4%). The main polar lipids were phosphatidyl methylethanolamine, phosphatidyl glycerol, diphosphatidyl glycerol, phosphatidyl inositol, one unidentified phospholipid, and one unknown polar lipid. The G+C content of strain BGMRC 2031T was 55.4%. Strain BGMRC 2031T could extend the mean lifespan and maximum lifespan of Caenorhabditis elegans by 4.5% and 12.5%, respectively. Overall, the results of this study indicate that BGMRC 2031T is a novel species in a new genus, for which the name Bruguierivorax albus gen. nov. sp. nov. is proposed, and the type of strain is designated as BGMRC 2031T (= NBRC 111907T = KCTC 52119T). In addition, a novel family, Bruguierivoracaceae fam. nov., is proposed to accommodate the genera Bruguierivorax, Biostraticola, and Sodalis.