Frateuria defendens sp. nov., bacterium isolated from the yellows grapevine's disease vector Hyalesthes obsoletus

A Dyella-like bacterium was previously isolated from the planthopper Hyalesthes obsoletus (Hemiptera). Based on its 16S rRNA gene sequence, strain DHo^T was assigned to the family Rhodanobacteraceae with Dyella and Frateuria as its closest relatives. The closest 16S rRNA gene sequences were Frateuria aurantia DSM 6220^T (98.2 %), Dyella thiooxydans ATSB10^T (98 %), Dyella terrae JS14-6^T (97.8 %) and Dyella marensis CS5-B2^T (97.8 %). Strain DHo^T is a Gram-negative, aerobic, motile, yellow-pigmented, rod-shaped bacterium. Strain DHo^T cells grew well at 28-30 °C and at pH 6.5-7.5 on a nutrient agar plate. DNA-DNA hybridization showed that the relatedness between strain DHo^T and D. jiangningensis strain SBZ3-12^T, and F. aurantia DSM 6220^T was 42.7 and 42.6 %, respectively. Ubiquinone Q-8 was the predominant respiratory quinone, and the major fatty acids (>10 %) were iso-C15 : 0, iso-C16 : 0 and iso-C17 : 0. In silico analysis based on phylogenetics and sequence identity at the nucleotide and protein levels suggests that Frateuria is the closest known relative of strain DHo^T. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain DHo^T was designated as a novel species of the genus Frateuria, for which the name Frateuria defendens sp. nov. is proposed. The type strain is DHo^T (=NCCB 100648^T; =DLB^T=DSM 106169^T).