Flaviaesturariibacter Luteus Sp Nov., Isolated From An Agricultural Floodplain Soil, And Emended Description Of The Genus Flaviaesturariibacter

A novel slow-growing bacterial strain designated as AW305(T) was isolated from an agricultural floodplain soil located in Mashare, Kavango region, Namibia. Cells stained Gram-negative, were non-motile, non-spore-forming, coccoid to rod-shaped and did not form a capsule. Colonies were yellow-pigmented, but flexirubin-type pigments were not detected. AW305(T) had an aerobic chemo-organoheterotrophic metabolism, using a narrow spectrum of carbon sources for growth, with preference for complex protein substrates, organic acids and amino acids. AW305(T) was able to grow at 15-40 degrees C, pH 5.3-8.3 and in the presence of up to 0.25% (w/v) NaCl. 16S rRNA gene sequence comparison showed that AW305(T) belonged to the genus Flaviaesturariibacter (family Chitinophagaceae). Its closest relatives were Flaviaesturariibacter amylovorans GCR0105T (97.0 %), Flavisolibacter ginsengiterrae Gsoil 492(T) (93.6 %) and Flavisolibacter ginsengisoli Gsoil 643(T) (93.2 %). DNA-DNA hybridization experiments corroborated that AW305(T) represents an independent genomospecies. The genomic DNA G+C content was 57.6 mol%. Major fatty acids were iso-C-15 : 1 G, iso-C-15 : 0, C-16 : (1)omega 5c, iso-C-17 : 0 3-OH and summed feature 3 (C-16 : (1)omega 7c and/or iso-C-15 : 0 2-OH). The predominant respiratory quinone was MK-7, albeit minor amounts of MK-6 were also detected. The polar lipids comprised major amounts of phosphatidylethanolamine and minor amounts of two unidentified lipids, an unidentified phospholipid, an unidentified glycolipid and an unidentified aminoglycophospholipid. On the basis of the polyphasic characterization, strain AW305(T) represents a novel species of the genus Flaviaesturariibacter for which the name Flaviaesturariibacter luteus sp. nov. is proposed, with the type strain AW305(T) (= DSM 100282(T) = LMG 29416(T)).