Martelella alba sp. nov., isolated from mangrove rhizosphere soil within the Beibu Gulf

Strain BGMRC 2036^T was isolated from rhizosphere soil of Bruguiear gymnorrhiza collected from the Beibu Gulf of China. Optimum growth occurred at 28 °C, pH 7.0, and under the conditions of 3-5% (w/v) NaCl. The phylogenetic comparisons of 16S rRNA gene sequences displayed that strain BGMRC 2036^T was closely related to Martelella limonii NBRC109441^T (96.6% sequence similarity), M. mediterranea CGMCC 1.12224^T (96.5%), M. lutilitoris GH2-6^T (96.5%), M. radicis BM5-7^T (96.2%), and M. mangrove BM9-1^T (95.9%), M. suaedae NBRC109440^T (95.8%). The phylogenomic tree based on the up-to-date bacterial core gene set indicated that the strain BGMRC 2036^T form a clade formed with members of the genera Martelella. The major polar lipids include phosphatidylmethylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphotidylinositol, two unidentified phospholipids, and three unidentified ninhydrin positive phospholipids. The major respiratory quinone is Q-10, which is similar to those of genera Martelella. The main cellular fatty acids are C_18:1 ω7c, C_16:0, and C_12:0 aldehyde. Genome sequencing revealed a genome size of 4.99 Mbp and a G + C content of 62.3 mol%. Pairwise comparison of the genomes of the new strain BGMRC 2036^T and the three reference strains M. endophytica YC 6887^T, M. mediterranea CGMCC 1.12224^T, and M. mangrovi USBA-857 indicated that gANI value was lower than 81% and a digital DNA-DNA hybridization value was lower than 27%. The strain BGMRC 2036^T possessed genes putatively encoding riboflavin synthesis and flavodoxin A polyphasic taxonomic study suggested that strain BGMRC 2036^T represented a novel species belonging to the genus Martelella, and it was named Martelella alba sp. nov. The type strain is BGMRC 2036^T (=KCTC 52121^T =NBRC 111908^T).