sp. nov., a novel chitin-degrading bacterium isolated from crawfish pond sediment.

A novel Gram-stain-negative, curved rod-shaped, motile and chitin-degrading strain, designated CD1, was isolated from crawfish pond sediment in Caidian District (30° 58' N 114° 03' E), Wuhan City, Hubei Province, PR China. Growth of this strain was observed at 15-40°C (optimum between 28 and 30 °C), at pH 7.0-9.0 (optimum between pH 7.0 and 8.0) and with 0-1 % (w/v) NaCl (optimum at 0 %). With respect to the 16S rRNA gene sequences, strain CD1 had the highest similarity (96.91-97.25 %) to four type strains of the genera '' and within the family . The phylogenetic trees based on genome sequences and 16S rRNA gene sequences indicated that strain CD1 was close to members of these two genera, in particular to the genus . The genomic DNA G+C content of strain CD1 was 64.8 mol%. The average nucleotide identity and the Genome-to-Genome Distance Calculator results showed low relatedness (below 95 and 70 %, respectively) between strain CD1 and the closely related type strains. Ubiquinone-8 was the predominant quinone. The major cellular fatty acids were C, C, summed feature 3 (C ω7 and/or C ω6) and summed feature 8 (C 7 and/or C 6). The polar lipid profile was composed of a mixture of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, four unidentified lipids, two unidentified phospholipids, two unidentified aminolipids and an unidentified aminoglycolipid. On the basis of the evidences presented in this study, strain CD1 represents a novel species of the genus , for which the name sp. nov. is proposed, with strain CD1 (=CCTCC AB 2022395=KCTC 92850) as the type strain.