Kribbella amoyensis sp. nov., isolated from rhizosphere soil of a pharmaceutical plant, Typhonium giganteum Engl.

An actinomycete, designated XMU 198(T), was isolated from the rhizosphere soil of a pharmaceutical plant, Typhonium giganteum Engl., collected in Xiamen City, China. 16S rRNA gene sequence analysis showed that the isolate exhibited highest sequence similarities with Kribbella flavida KACC 20148(T), K. karoonensis Q41(T) and K. alba YIM 31975(T) (98.7, 98.4 and 98.2 %, respectively). The chemotaxonomic characteristics further supported the assignment of strain XMU 198(T) to the genus Kribbella: ll-diaminopimelic acid in the cell-wall peptidoglycan; glucose and galactose with minor amounts of ribose as the whole-cell sugars; polar lipids comprising phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, phosphatidylinositol and unidentified phospholipids; a fatty acid profile characterized by the predominance of iso-C(16 : 0), iso-C(14 : 0) and anteiso-C(15 : 0); and MK-9(H(4)) as the main menaquinone. Gyrase subunit B gene (gyrB) sequence analysis showed that the genetic distances between strain XMU 198(T) and all other members of the genus Kribbella were greater than 0.014, the value used as the threshold for species delineation within this genus. A wide range of genotypic and phenotypic characteristics, as well as DNA-DNA relatedness between strain XMU 198(T) and K. flavida DSM 17836(T) (41.18 %), K. karoonensis Q41(T) (38.02 %) and K. alba DSM 15500(T) (50.58 %), distinguished the isolate from its closest phylogenetic neighbours. On the basis of the above data, a novel species of the genus Kribbella, Kribbella amoyensis sp. nov., is proposed. The type strain is XMU 198(T) ( = DSM 24683(T) = NBRC 107914(T)).