Aequorivita vitellina sp. nov. and Aequorivita xiaoshiensis sp. nov., isolated from marine sediment

Two Gram- stain-negative, strictly aerobic, chemoheterotrophic, short- rod-shaped and non-motile strains, forming yellow colonies and designated F47161T and F64183T, were isolated from marine sediment of Xiaoshi Island, Wei Hai, PR China. Strain F47161T grew at 15-37 & DEG;C (optimally at 30 & DEG;C) and pH 6.0-9.0 (optimally at pH 7.5) and in the presence of 1-9 % (w/v) NaCl (optimally at 3 %). Strain F64183T grew at 10-37 & DEG;C (optimally at 30 & DEG;C) and pH 6.0-8.5 (optimally at pH 7.0) and in the presence of 1-8 % (w/v) NaCl (optimally at 3 %). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that F47161T and F64183T were related to members of the genus Aequorivita. The strains shared 97.4 % 16S rRNA gene sequence similarity to each other. F47161T and F64183T shared highest 16S rRNA gene sequence similarity to Aequorivita sinensis JCM 19789T, and the values were 97.5 % and 98.4 %, respectively. The predominant cellular fatty acids of both F64183T and F47161T were iso-C15: 0 and iso- C17: 0 3 -OH, but the predominant fatty acids of F47161T also included anteiso-C15:0. The sole respiratory quinone of F47161T and F64183T was menaquinone 6 (MK -6), consistent with that observed for all related strains. Between F47161T and F64183T, the average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values were 75.8 % and 20.5 %, respectively, and between the novel isolates (F47161T and F64183T) and A. sinensis JCM 19789T they were 76.0 % and 94.2 % and 20.6 % and 57.1 %, respectively. The genomic DNA G+C contents of F47161T and F64183T was 37.3 % and 34.5 %, respectively. The polar lipid profiles of F47161T and F64183T contained phosphatidylethanolamine, two aminolipids, one glycolipid, one phosphoglycolipid and two unidentified polar lipids. Differential phenotypic and genotypic characteristics of the two strains indicated that the two strains should be classified as representing two novel species of the genus Aequorivita, for which the names Aequorivita vitellina sp. nov. and Aequorivita xiaoshiensis sp. nov. are proposed. The type strains are F47161T (=MCCC 1H00509T=KCTC 92017T) and F64183T (=MCCC 1H00507T=KCTC 92016T), respectively.

Automated summary

Two novel species of the genus Aequorivita, named as Aequorivita vitellina sp. nov. and Aequorivita xiaoshiensis sp. nov., were isolated from marine sediment of Xiaoshi Island, Wei Hai, PR China. These strains showed distinct phenotypic and genotypic characteristics, supporting their classification as novel species.