Description of Ancylobacter oerskovii sp nov and two additional strains of Ancylobacter polymorphus

Abstract

A Gram-negative, pleomorphic, rod-shaped, non-spore-forming bacterium, designated strain NS05(T), was isolated from soil after enrichment with oxalate. On the basis of 16S rRNA gene sequence similarity, strain NS05(T) was shown to be phylogenetically related to the genera Ancylobacter, Starkeya and Angulomicrobium (96.3-98.1 % sequence similarity), class Alphaproteobacteria. Strain NS05(T) was most closely related to Ancylobacter rudongensis AS 1.1761(T) (98.1 % sequence similarity). The whole-cell fatty acid pattern of strain NS05(T) was typical of those found in members of the genus Ancylobacter. Its main components were C-18:1 omega 7c (60.4 %), C-19: 0 omega 8c cyclo (28.3 %) and C-16:0 (7.4 %) and hydroxylated compounds were absent. The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain NS05(T) with respect to the four Ancylobacter species with validly published names. Therefore, it is concluded that NS05(T) represents a novel species of the genus Ancylobacter, for which the name Ancylobacter oerskovii sp. nov. is proposed. The type strain is NS05(T) (=DSM 18746(T) =CCM 7435(T)). Two other oxalate-utilizing strains, NS03 and NS04, isolated from paper-mill effluents, were shown by 16S rRNA gene sequence analysis to be affiliated to the species Ancylobacter polymorphus. The study of their physiological properties extends the knowledge of the physiological variability within this species.