Aerophototrophica crusticola gen. nov., sp. nov., isolated from desert biocrusts

A pink-pigmented, Gram- stain-negative, rod-shaped, strictly aerobic bacterial strain MIMtkB3(T), was isolated from moss crusts in Hunshandake desert of China. Cells grew at 15?45 degrees C (optimum of 28 degrees C), at pH of 6.0?8.5 (optimum of 7.0) and with 0?1.0 % (w/v) NaCl (optimum of 0 %). The strain could biosynthesize the green-coloured pigment bacteriochlorophyll a (BChl a). The respiratory quinone was ubiquinone Q-10, while C18.1 omega 7c and C-18.1 2OH were the major fatty acids. Phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminophospholipid, one unidentified phospholipid, three unidentified glycolipid and one unidentified lipid were the major polar lipids. Strain MIMtkB3(T) was most closely related to Oleisolibacter albus NAU-10(T), Niveispirillum fermenti CC-LY736(T), and Rhodocista centenaria SW of the family Rhodospirillaceae with 16S rRNA gene similarities of 93.09, 92.02 and 91.73%, respectively. The genomic DNA G+C content calculated on complete genome sequencing was 69.3 mol%. The average nucleotide identity between strain MIMtkB3(T) and its closely related type strains in Rhodospirillaceae was below 77.96 % and digital DNA-DNA hybridization lower than 24.70 %. Full light utilization pathway of aerobic anoxygenic phototrophic bacteria was identified in the genome. Based on phenotypic, chemotaxonomic and phylogenetic characteristics, strain MIMtkB3(T) represents a novel genus of the family Rhodospirillaceae, for which the name Aerophototrophica crusticola gen. nov., sp. nov. is proposed. The type strain is MIMtkB3(T) (=KCTC 42633(T)=MCCC 1K00570(T)).