Algoriphagus machipongonensis sp. nov., co-isolated with a colonial choanoflagellate

A Gram-negative, non-motile, non-spore-forming bacterial strain, PR1^T, was isolated from a mud core sample containing colonial choanoflagellates near Hog Island, Virginia, USA. Strain PR1^T grew optimally at 30 °C and with 3% (w/v) NaCl. Strain PR1^T contained MK-7 as the major menaquinone as well as carotenoids but lacked pigments of the flexirubin-type. The predominant fatty acids were iso-C_{15: 0} (29.4%), iso-C_{17: 1}ω9c (18.5%) and summed feature 3 (C_{16: 1}ω6c and/or C_{16: 1}ω7c; 11.3%). The major polar lipids detected in strain PR1^T were phosphatidylethanolamine, an unknown phospholipid, an aminophospholipid, an aminolipid and two lipids of unknown character. The DNA G+C content was 38.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain PR1^T fell within the cluster comprising the genus Algoriphagus and was most closely related to Algoriphagus halophilus JC 2051^T (95.4% sequence similarity) and Algoriphagus lutimaris S1-3^T (95.3% sequence similarity). The 16S rRNA gene sequence similarity between strain PR1^T and the type strains of other species of the genus Algoriphagus were in the range 91-95%. Differential phenotypic properties and phylogenetic and genetic distinctiveness of strain PR1^T demonstrated that this strain was distinct from other members of the genus Algoriphagus, including its closest relative, A. halophilus. Based on phenotypic, chemotaxonomic, phylogenetic and genomic data, strain PR1^T should be placed in the genus Algoriphagus as a representative of a novel species, for which the name Algoriphagus machipongonensis sp. nov. is proposed. The type strain is PR1^T (5ATCC BAA-2233^T 5DSM 24695^T).