Nesterenkonia aurantiaca sp nov., an alkaliphilic actinobacterium isolated from Antarctica

A Gram-stain-positive, non-endospore-forming, haloalkaliphilic actinobacterium, strain CK5(T), was isolated from a soil sample, collected at Cape King (Antarctica), and its taxonomic position was investigated by using a polyphasic approach. Cells were cocci with orange pigmentation, non-motile and grew optimally at 25 degrees C and pH 9.0-9.5 in the presence of 2 % (w/v) NaCl. Cellular membrane contained MK-7 (72 %) and MK-8 (28 %), and anteiso-C-15 : 0 (64.8 %), iso-C-16 : 0 (13.3 %), n-C17 :0 (9.9 /0), n -C16 :0 (4.0 %), n -C14 :0 (3.7 %) as major cellular fatty acids. The DNA G+C content was 64.8 mol%. Strain CK5T, based on the 16S rRNA gene sequence similarity, was most closely related to Nesterenkonia jeotgali JG-241(T) (99.5 %), Nesterenkonia sandarakina YIM 70009(T) (99.4 %), Nesterenkonia lutea YIM 70081(T) (99.4 %), Nesterenkonia halotolerans YIM 70084(T) (99.3 %), Nesterenkonia xinjiangensis YIM 70097(T) (97.2 %), Nesterenkonia flava CAAS 251T (97.1 %) and Nesterekonia aethiopica CCUG 48939(T) (97.1 %). Strain CK5T revealed 31 % DNA DNA relatedness with respect to N. sandarakina DSM 15664T, 29 % with respect to N. jeotgali DSM 19081(T), 10 % with respect to N. lutea DSM 15666(T) and 1 % with respect to N. halotolerans, DSM 15474(T), N. xinjiangensis DSM 15475(T), N. aethiopica DSM 1 7733T and N. flava DSM 19422(T). On the basis of 16S rRNA gene sequences, DNA DNA hybridization and chemotaxonomic characteristics, strain CK5T represents a novel species of the genus Nesterenkonia, for which the name Nesterenkonia aurantiaca sp. nov. is proposed. The type strain is CK5(T) (=DSM 27373(T)=JCM 19723(T)).