Starkeya koreensis sp nov., isolated from rice straw

Abstract

A facultatively chemolithoautotrophic, Gram-negative, aerobic, highly curved rod-shaped, nonmotile, non-spore-forming bacterium, strain Jip08(T), was isolated from rice straw in Daejeon, South Korea. Strain Jip08(T) produced colourless colonies (1.0-1.5 mm) on R2A medium after 3 days. On the basis of 16S rRNA gene sequence similarity, strain Jip08(T) was shown to belong to the alpha-2 subclass of the Proteobacteria, and was most closely related to Starkeya novella IAM 12100(T) (98.6%), Angulomicrobium tetraedale DSM 5895(T) (98.1%), Angulomicrobium amanitiforme NCIMB 1785(T) (98.0%), Ancylobacter aquaticus ATCC 25396(T) (96.6%) and Methylorhabdus multivorans DM13(T) (95.8%), all of which belong to the family Hyphomicrobiaceae. The genomic DNA G + C content of strain Jip08(T) was 69 mol%. Chemotaxonomic data [major ubiquinone, Q-10; major fatty acids, C-18:1 isomer (summed feature of C-18:1 omega 7c/omega 9t/omega 12t), C-19:0 cyclo omega 8c and C-16:0], 16S rRNA gene sequence analyses and some morphological and physiological features supported the affiliation of strain Jip08(T) to the genus Starkeya. However, DNA-DNA hybridization data and some phenotypic properties showed that strain Jip08(T) could be distinguished from the single known Starkeya species and represented a novel species, for which the name Starkeya koreensis sp. nov. is proposed. The type strain is Jip08(T) (= KCTC 12212(T) = NBRC 100963(T) = IAM 15215(T)).