Description of Algoriphagus taiwanensis sp. nov., a xylanolytic bacterium isolated from surface seawater, and emended descriptions of Algoriphagus mannitolivorans, Algoriphagus olei, Algoriphagus aquatilis and Algoriphagus ratkowskyi.

A novel, Gram-stain negative, strictly aerobic, oval or rod-shaped, red-pigmented, non-spore-forming xylanolytic bacterial strain, designated CC-PR-82(T), was isolated from surface seawater of Pingtung coast, Taiwan, and characterized by polyphasic taxonomy. Strain CC-PR-82(T) shared highest pairwise 16S rRNA gene sequence similarity to Algoriphagus mannitolivorans IMSNU 14012(T) (97.0 %) followed by 'A. boseongensis' BS-R1(T) (96.5 %) and A. olei CC-Hsuan-617(T) (95.6 %), whereas other (n = 26) Algoriphapus species shared 95.6-92.6 % sequence similarities. The novel strain further established a distinct phyletic lineage tightly associated with Algoriphagus species. The DNA-DNA hybridization value obtained between CC-PR-82(T) and A. mannitolivorans DSM 15301(T) was 29.0 % (33.4 % reciprocal using A. mannitolivorans DSM 15301(T) probe). The major (>5 % of total) fatty acids were identified as iso-C15:0, C16:1 ω6c and/or C16:1 ω7c, iso-C16:0, iso-C17:1 ω9c and/or C16:0 10-methyl, anteiso-C15:0 and C17:1 ω6c. Polar lipids included major amounts of an unidentified aminolipid and an unidentified lipid; moderate amounts of phosphatidylethanolamine, phosphatidylserine and an unidentified aminolipid; trace amounts of an unidentified phospholipid, an unidentified lipid and an unidentified glycolipid. The DNA G+C content was determined to be 42.3 mol%. Menaquinone-7 was the sole respiratory quinone. Based on the polyphasic characteristics, that are in line with those of Algoriphagus species, in addition to distinguishing phylogenetic and phenotypic features, strain CC-PR-82(T) appears to represent a novel species of the genus Algoriphagus, for which the name Algoriphagus taiwanensis sp. nov. (type strain CC-PR-82(T) = JCM 19755(T) = BCRC 80746(T)) is proposed. In addition, emended descriptions of the species A. mannitolivorans, A. aquatilis, A. olei and A. ratkowskyi are also proposed.