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4852

A Gram-stain-negative, elongated rod-shaped, motile by gliding, green-pigmented, aerobic bacterial strain, designated LY03T, was isolated from lake water in Xiamen, Fujian Province, China. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the isolate was a member of the genus Chitinimonas , which belongs to the family Burkholderiaceae . Strain LY03T was most closely related to Chitinimonas taiwanensis LMG 22011T (96.02 % 16S rRNA gene sequence similarity), followed by Chitinimonas koreensis KACC 11467T (94.85 %), and the three strains formed a distinct lineage from other strains in the phylogenetic analyses. Optimum conditions for growth were 37 °C, pH 7–9 and without NaCl. The major fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and C10 : 0 3-OH. The DNA G+C content of strain LY03T was 63.6 mol% and the major respiratory quinone was ubiquinone-8 (Q-8). The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unknown polar lipids and unidentified phospholipids. Differential phenotypic properties and phylogenetic distinctiveness distinguished strain LY03T from all other members of the genus Chitinimonas . On the basis of its morphology, physiology, fatty acid composition and 16S rRNA gene sequence data, strain LY03T represents a novel species of the genus Chitinimonas , for which the name Chitinimonas prasina sp. nov. is proposed. The type strain is LY03T ( = MCCC 1F01209T = KCTC 32574T).

Summary In an acetate‐fed anaerobic–aerobic membrane bioreactor with deteriorated enhanced biological phosphorus removal ( EBPR ), D efluviicoccus ‐related tetrad‐forming organisms ( DTFO ) were observed to predominate in the microbial community. Using metagenomics, a partial genome of the predominant DTFO , ‘ C andidatus   D efluviicoccus tetraformis strain TFO 71’, was successfully constructed and characterized. Examining the genome confirmed the presence of genes related to the synthesis and degradation of glycogen and polyhydroxyalkanoate ( PHA ), which function as energy and carbon storage compounds. TFO 71 and ‘ C andidatus   A ccumulibacter phosphatis’ ( CAP ) UW ‐1 and CAP UW ‐2, representative polyphosphate‐accumulating organisms ( PAO ), have PHA metabolism‐related genes with high homology, but TFO 71 has unique genes for PHA synthesis, gene regulation and granule management. We further discovered genes encoding DTFO polyphosphate ( polyP ) synthesis, suggesting that TFO 71 may synthesize polyP under untested conditions. However, TFO 71 may not activate these genes under EBPR conditions because the retrieved genome does not contain all inorganic phosphate transporters that are characteristic of PAOs ( CAP UW ‐1, CAP UW ‐2, M icrolunatus phosphovorus   NM ‐1 and T etrasphaera species). As a first step in characterizing EBPR ‐associated DTFO metabolism, this study identifies important differences between DTFO and PAO that may contribute to EBPR community competition and deterioration.