Pseudohoeflea coraliihabitans sp. nov., a poly-β-hydroxybutyrate-producing, halotolerant bacterium isolated from coral sediment in the Dapeng peninsula (Guangdong, China).

Abstract

A Gram-stain-negative, strictly aerobic, motile, flagellated, rod-shaped, halotolerant, and poly-β-hydroxyalkanoate-producing bacterium, designated DP4N28-3^T, was isolated from offshore sediment surrounding hard coral in the Dapeng peninsula (Guangdong, PR China). Growth occurred at 15-35 °C (optimal at 30 °C), pH 6.0-9.5 (optimal at 6.0-7.0), and 0.0-30.0 % NaCl concentration (w/v, optimal at 0.0-2.0 %), showing halotolerance. Phylogeny based on 16S rRNA gene sequences, five housekeeping genes, and genome sequences identified Pseudohoeflea suaedae DSM 23348^T (98.1 %, 16S rRNA gene sequence similarity) as the most related species to strain DP4N28-3^T. Average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values between strain DP4N28-3^T and P. suaedae DSM 23348^T were all below the threshold of species demarcation. Major phenotypic differences were the flagella type and the limited sources of single carbon utilization by strain DP4N28-3^T, which only included acetic acid, acetoacetic acid, d-glucuronic acid, and glucuronamide. Strain DP4N28-3^T harboured the class I poly-β-hydroxyalkanoate synthase gene (phaC) and produced poly-β-hydroxybutyrate. The fatty acids were summed feature 8 (C_18 : 1  ω6c and/or C_18 : 1  ω7c, 49.4 %) and C_16 : 0 (13.4 %). The major cellular polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, and sulfoquinovosyl diacylglycerol. The respiratory quinone was Q-10. The results of the phylogenetic, genomic, phenotypic, and chemotaxonomic analysis indicated that the isolated strain represents the type strain of a novel species. Based on these results, strain DP4N28-3^T (=MCCC 1K05639^T=KCTC 82803^T) is proposed as the type strain of the novel species Pseudohoeflea coraliihabitans sp. nov.