Pontibacter oryzae sp. nov., a carotenoid-producing species isolated from a rice paddy field

Abstract

A taxonomic study using a polyphasic approach was performed on a Gram-stain negative, red-pink, aerobic, non-motile, asporogenous, rod-shaped bacterium, designated strain KIRAN(T), isolated from soil collected from a rice paddy field. The 16S rRNA gene sequence analysis showed that strain KIRAN(T) is phylogenetically related to Pontibacter actiniarum KMM 6156(T), Pontibacter korlensis X14-1(T), Pontibacter odishensis JC130(T), Pontibacter litorisediminis YKTF-7(T) and Pontibacter aurantiacus NP1(T) (97.6, 97.5, 97.3, 97.3 and 96.7% sequence similarity, respectively). The major fatty acids of strain KIRAN(T) were identified as iso-C-15:0, iso-C-15:0 3-OH and summed feature 4. The predominant menaquinone was identified as MK-7. The polar lipid profile was found to consist of phosphatidylethanolamine, four unidentified phospholipids, an unidentified glycolipid, an unidentified aminolipid and four unidentified lipids. The genome of strain KIRAN(T) has a G + C content of 48.3 mol%. The in silico DNA-DNA hybridization and average nucleotide identity values between strain KIRAN(T) and the closely related strains P. actiniarum KMM 6156(T) and P. korlensis X14-1(T) were 21.2%/21.8% and 76.4%/75.1%, respectively. On the basis of the data from phenotypic tests and genotypic differences between strain KIRAN(T) and its close phylogenetic relatives, strain KIRAN(T) is concluded to represent a new species belonging to the genus Pontibacter, for which the name Pontibacter oryzae sp. nov. is proposed. The type strain is KIRAN(T) (= KACC 19815(T) = JCM 32880(T)).