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

Abstract

A Gram-negative, non-motile, non-spore-forming bacterial strain, PR1[superscript T], was isolated from a mud core sample containing colonial choanoflagellates near Hog Island, Virginia, USA. Strain PR1[superscript T] grew optimally at 30 °C and with 3 % (w/v) NaCl. Strain PR1[superscript 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-C15 : 0 (29.4 %), iso-C17 : 1ω9c (18.5 %) and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c; 11.3 %). The major polar lipids detected in strain PR1[superscript 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[superscript T] fell within the cluster comprising the genus Algoriphagus and was most closely related to Algoriphagus halophilus JC 2051[superscript T] (95.4 % sequence similarity) and Algoriphagus lutimaris S1-3[superscript T] (95.3 % sequence similarity). The 16S rRNA gene sequence similarity between strain PR1[superscript 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[superscript 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[superscript 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[superscript T] ( = ATCC BAA-2233[superscript T] = DSM 24695[superscript T]).