Kineothrix alysoides, gen. nov., sp. nov., a saccharolytic butyrate-producer within the family Lachnospiraceae

An anaerobic, saccharolytic, spore-forming, butyrate-producing bacterium, strain KNHs209T, was isolated from a switchgrass microcosm seeded with forest soil. Cells were highly motile rods, often forming long filamentous chains which were easily observed moving under the microscope. Its closest phylogenetic relative was Eisenbergiella tayi (16S rRNA gene sequence identity 94.2 %), although it was easily distinguishable based on its morphology and physiology. Whole-genome sequencing enabled development of a minimal medium, and also suggested that the organism is capable of fixing nitrogen. Its wide variety of growth substrates was mirrored by a high number of encoded chemotaxis receptors (45, the highest in the family Lachnospiraceae). Strain KNHs209T utilized a wide variety of carbohydrates, but not cellulose or xylan. Fermentation products included formate, acetate and butyrate; sulfur compounds and nitrate were not reduced. Strain KNHs209T grew optimally at 35-40 °C and pH 7. The genomic DNA G+C content was 42.74 mol%; the major membrane fatty acids were C14 : 0 and C16 : 0. Based on phenotypic, genomic, phylogenetic and chemotaxonomic analyses, this organism represents a novel genus and species within the family Lachnospiraceae for which the name Kineothrix alysoides, gen. nov., sp. nov. is proposed. The type strain is KNHs209T (=ATCC TSD-26T=DSM 100556T).