Haloferula rosicola sp. nov., an endophytic bacterium isolated from the root of a halophyte, Rosa rugosa and emended description of the genus Haloferula

Abstract

A Gram-negative, non-spore forming endophytic bacterial strain YC6886T, was isolated from the root of a halophyte, Rosa rugosa, inhabiting coastal areas of Namhae island, located off southern end of Korea. The Cells were non-motile, obligately aerobic, and rod-shaped and formed colonies that were pale yellow in colour. The strain was able to grow at 4-32 degrees C (optimum at 25-28 degrees C) and at pH 6.5-9.5 (optimum at pH 7.5). It grew optimally in 2-3 % (w/v) NaCl, but NaCl was not an absolute requirement for growth. Strain YC6886T produced yellow carotenoid pigments. Comparison of 16S rRNA gene sequences showed that the strain was a member of the genus Haloferula, a member of phylum Verrucomicrobia, exhibiting highest similarity with Haloferula sargassicola MN1-1037T (97.4 %). Sequence similarities of the strain YC6886T to the other Haloferula type strains were 93.9-94.7 %. The DNA-DNA relatedness values of the strain YC6886T with H. sargassicola KCTC 22202T and H. rosea KCTC 22201T were 27 and 15 %, respectively. The predominant fatty acids were iso-C14:0, C16:0 and C16:1omega9c. The major respiratory quinone was menaquinone-9 and the DNA G+C content was 58.5 mol%. On the basis of phenotypic, chemotaxonomic, DNA-DNA hybridization data and phylogenetic analysis, strain YC6886T represents a novel species in the genus Haloferula, for which the name Haloferula rosicola sp. nov. is proposed. The type strain is YC6886T (= KCTC 22447T = DSM 21608T).