Parasutterella secunda sp. nov., isolated from human faeces and proposal of Sutterellaceae fam. nov. in the order Burkholderiales

<jats:p>A novel, strictly anaerobic, non-spore-forming, Gram-reaction-negative coccobacillus bacterium, designated strain YIT 12071<jats:sup>T</jats:sup>, was isolated from human faeces. Biochemically, this strain was largely unreactive and asaccharolytic. Growth of this strain in peptone-yeast-extract broth was weak, producing no visible turbidity, and no short-chain fatty acids were detected as an end product of metabolism. Following 16S rRNA gene sequence analysis, strain YIT 12071<jats:sup>T</jats:sup>was found to be most closely related to<jats:italic>Parasutterella excrementihominis</jats:italic>(90 % sequence similarity) and phylogenetically distinct from other known genera belonging to the order<jats:italic>Burkholderiales</jats:italic>. Biochemical data supported the affiliation of this strain with the genus<jats:italic>Parasutterella</jats:italic>. Strain YIT 12071<jats:sup>T</jats:sup>, therefore, represents a novel species of the genus<jats:italic>Parasutterella</jats:italic>, for which the name<jats:italic>Parasutterella secunda</jats:italic>sp. nov. is proposed. The type strain is YIT 12071<jats:sup>T</jats:sup>(=DSM 22575<jats:sup>T</jats:sup>=JCM 16078<jats:sup>T</jats:sup>). On the basis of 16S rRNA gene sequence analysis, species of the genera<jats:italic>Sutterella</jats:italic>and<jats:italic>Parasutterella</jats:italic>form a distinct and deep evolutionary lineage of descent in the order<jats:italic>Burkholderiales</jats:italic>. This lineage could not be associated with any of the four known families of the order<jats:italic>Burkholderiales</jats:italic>. The distinct phylogenetic position and the unusual combination of chemotaxonomic characteristics shared by these genera, such as the predominant quinones and cellular fatty acid compositions, suggest that they constitute a novel family in the order<jats:italic>Burkholderiales</jats:italic>, for which the name<jats:italic>Sutterellaceae</jats:italic>fam. nov. is proposed to accommodate the genera<jats:italic>Sutterella</jats:italic>and<jats:italic>Parasutterella</jats:italic>.</jats:p>