Jannaschia maritima sp. nov., a novel marine bacterium isolated from the biofilm of concrete breakwater structures.

Marine biofilms were newly revealed as a bank of hidden microbial diversity and functional potential. In this study, a Gram-stain-negative, aerobic, oval and non-motile bacterium, designated LMIT008^T, was isolated from the biofilm of concrete breakwater structures located in the coastal area of Shantou, PR China. Strain LMIT008^T was found to grow at salinities of 1-7% NaCl, at pH 5-8 and at temperatures 10-40 °C. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain LMIT008^T belonged to the genus Jannaschia and was closely related to the type strains Jannaschia aquimarina KCTC23555^T (96.03%) and Jannaschia marina SHC-163^T (95.31%). The draft genome size of the strain LMIT008^T was 3.67 Mbp, and the genomic DNA G+C content was 69.83 mol%. The average nucleotide identity value between strain LMIT008^T and the closely related type strain J. aquimarina KCTC23555^T was 74.82%. The predominant cellular fatty acids were identified as summed feature 8 (C_18 : 1  ω7c/C_18 : 1  ω6c) and C_18 : 0, and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Ubiquinone-10 (Q-10) is the sole respiratory quinone. Further, genomic analysis of strain LMIT008^T showed that the strain harbours abundant genes associated with biofilm formation and environmental adaption, explaining the potential strategies for living on concrete breakwater structures. Based on the morphological, phylogenetic, chemotaxonomic and phenotypic characterization, the strain LMIT008^T was considered to represent a novel species in the genus of Jannaschia, for which the name Jannaschia maritima sp. nov. was proposed, with LMIT008^T (=MCCC 1K08854^T=KCTC 8321^T) as the type strain.