Nocardioides palaemonis sp. nov. and Tessaracoccus palaemonis sp. nov., isolated from the gastrointestinal tract of lake prawn

Two novel Gram- stain-positive, non-motile and non- spore-forming bacterial strains, designated J2M5(T) and J1M15(T), were iso-lated from the gastrointestinal tract of a lake prawn Palaemon paucidens. Strain J2M5(T) was an obligately aerobic bacterium that formed milky-coloured colonies and showed a rod-coccus cell cycle, while strain J1M15(T) was a facultatively aerobic bacterium that formed orangish- yellow-coloured colonies and showed rod-shaped cells. Strains J2M5(T) and J1M15(T) showed the highest 16S rRNA gene sequence similarity to Nocardioides ganghwensis JC2055(T) (98.63 %) and Tessaracoccus flaves-cens SST-39T (98.08 %), respectively. The whole-genome sequence of strain J2M5(T) was 4.52 Mbp in size and the genomic G+C content directly calculated from the genome sequence of strain J2M5(T) was 72.5 mol%. The whole-genome sequence of strain J1M15(T) was 3.20 Mbp in size and the genomic G+C content directly calculated from the genome sequence of strain J1M15(T) was 69.6mol %. Strains J2M5(T) and J1M15(T) showed high OrthoANI similarity to N. ganghwensis JC2055(T) (83.6 %) and T. flaves-cens (77.2 %), respectively. We analysed the genome sequences of strains J2M5(T) and J1M15(T) in terms of carbohydrate-active enzymes, antibiotic resistance genes and virulence factor genes. Strains J2M5(T) and J1M15(T) contained MK -8 (H4) and MK -9 (H4) as the predominant respiratory quinones, respectively. The major polar lipids of both strains were phosphatidylglycerol and diphosphatidylglycerol. Additionally, strain J2M5(T) possessed phosphatidylcholine, phosphatidylserine and phosphatidy-lethanolamine. The cellular sugar components of strain J2M5(T) were ribose, mannose, glucose and galactose, and its cellular amino acid components were l-alanine and l -lysine. The cellular sugar components of strain J1M15(T) were rhamnose, ribose, mannose and glucose, and its cellular amino acid component was l-alanine. The major cellular fatty acids of strains J2M5(T) and J1M15(T) were iso- C16: 0 and anteiso-C15:0, respectively. The multiple taxonomic analyses indicated that strains J2M5(T) and J1M15(T) represent novel species of the genus Nocardioides and Tessaracoccus, respectively. We propose the names Nocardioides palae-monis sp. nov. and Tessaracoccus palaemonis sp. nov. for strain J2M5(T) (=KCTC 49461(T)=CCUG 74767(T)) and strain J1M15(T) (=KCTC 49462(T)=CCUG 74766(T)), respectively.

Automated summary

Two novel bacterial strains isolated from the gastrointestinal tract of a lake prawn were characterized and named as Nocardioides palae-monis sp. nov. and Tessaracoccus palaemonis sp. nov. The strains showed distinct characteristics, genomic sequences, and major chemical components.