Blastomonas quesadae sp nov., isolated from a saline soil by dilution-to-extinction cultivation

We isolated a Gram-stain-negative, aerobic bacterial strain, 912(T), from a soil sample taken from Rambla Salada (Murcia), south-eastern Spain, by using the dilution-to-extinction method. Cells of the strain were motile with a polar flagellum, short rod-shaped, catalase-and oxidase-positive and grew at NaCl concentrations within the range 0-5% (w/v) (optimum 3 %, w/v), at 4-32 degrees C (optimum 30 degrees C) and at pH 6-9 (optimum pH 7); bacteriochlorophyll a was produced. Analysis of the 16S rRNA gene sequence indicated that this strain belonged to the genus Blastomonas in the class Alphaproteobacteria. Its closest relatives were Blastomonas natatoria EY 4220(T), Blastomonas ursincola KR-99 T and Blastomonas aquatica PE 4-5(T), to which the strain showed 16S rRNA gene sequence similarity values of 95.9, 95.8 and 95.1 %, respectively. The DNA G+ C content was 63 mol%. The major fatty acids of strain 912(T) were C-18 : 1 omega 7c/C-18 : 1 omega 6c, C-16 : 1 omega 7c/C-16 : 1 omega 6c, C-16 : 0 and C-17 : 1 omega 6c. The predominant isoprenoid quinone was ubiquinone 10 (Q-10). The polar lipids contained diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, phosphoglycolipid, one unidentified phospholipid and two unidentified polar lipids. Based on the phylogenetic, genotypic, phenotypic and chemotaxonomic data, the strain represents a novel species of the genus Blastomonas, for which the name Blastomonas quesadae sp. nov. is proposed. Strain 912(T) (= CECT 9186(T) = LMG 29921(T)) is the type strain.