Maribacter litopenaei sp. nov., isolated from the intestinal tract of the Pacific white shrimp Litopenaeus vannamei

A Gram- stain-negative, aerobic, rod-shaped bacterial strain, designated HL-LV01T, was isolated from the intestinal tract content of the Pacific white shrimp Litopenaeus vannamei. The 16S rRNA gene sequence of strain HL-LV01T showed that the strain was clearly a member of the genus Maribacter. According to the phylogenetic analyses, strain HL-LV01T was most closely related to the species Maribacter flavus KCTC 42508T with 98.2 % sequence similarity. The average nucleotide identity and digital DNA- DNA hybridization values between strain HL-LV01T and M. flavus KCTC 42508T were 80.6 % and 23.0 %, respectively, indicating different genomic species in the genus Maribacter. Strain HL-LV01T showed optimal growth at 35 & DEG;C, pH 7.0, and 2.5 % (w/v) sea salts. The major cellular fatty acids were iso-C15: 0 (32.5 %), iso-C17: 0 3 -OH (22.3 %), and iso-C15: 1 G (15.5 %). The major res-piratory quinone was menaquinone-6. The polar lipids consisted of phosphatidylethanolamine, three unidentified aminolipids, and seven unidentified lipids. The genomic DNA G+C content of the strain was 39.8 mol%. The comprehensive phylogenetic, genomic, phenotypic, and chemotaxonomic results indicate that strain HL-LV01T is distinct from validly published species of the genus Maribacter. Hence, we propose strain HL-LV01T as a novel species belonging to the genus Maribacter, for which the name Maribacter litopenaei sp. nov. is proposed. The type strain is HL-LV01T (= KCCM 90498T = JCM 35709T).

Automated summary

A gram-negative, aerobic, rod-shaped bacterium called HL-LV01T was isolated from the intestinal tract content of the Pacific white shrimp Litopenaeus vannamei. Based on the 16S rRNA gene sequence analysis, strain HL-LV01T belongs to the genus Maribacter and is most closely related to Maribacter flavus KCTC 42508T. The strain exhibits different genomic characteristics compared to other species in the same genus.