Magnetovirga frankeli gen. Nov., sp. nov., a magnetotactic bacterium isolated from the Salton Sea, California, that represents a novel lineage in the Gammaprotoeobacteria

Abstract

A magnetotactic bacterium, designated strain SS-5^T, was isolated from the Salton Sea, a highly saline lake in California, USA, and cultivated in axenic culture. The Gram-negative cells of strain SS-5^T are relatively small and rod-shaped and possess a single polar flagellum (monotrichous). This strain is a magnetotactic bacterium producing magnetite nanocrystals aligned in one chain per cell. Strain SS-5^T is a microaerophile that grows chemolithoautotrophically while reducing oxygen as a terminal electron acceptor. Optimal growth occurred at pH 7.0–7.3 and 28–36 °C with thiosulfate used as an electron donor and sodium bicarbonate as a carbon source. Based on its genome sequence, the G + C content is 61.6 %. Phylogenomic and phylogenetic analyses indicate that strain SS-5^T belongs to the Sedimenticolaceae family within the Gammaproteobacteria class. Based on average amino acid identity, strain SS-5^T can be considered as a novel species of a new genus, for which the name Magnetovirga frankeli is proposed. The type strain of M. frankeli is SS-5^T (=DSM 116211^T = JCM 39467^T).