Vallitalea guaymasensis gen. nov., sp. nov., isolated from marine sediment

Abstract

A novel obligately anaerobic, non-spore-forming, rod-shaped mesophilic, halophilic, Gram-stain-negative bacterium, was isolated from sediments of Guaymas Basin. The strain, designated Ra1766G1T, grew at 20–40 °C (optimum, 30–35 °C) and at pH 6.0–8.0 (optimum, pH 6.5–7.5). It required 0.5–7.5 % NaCl (optimum, 2–3 %) for growth. Sulfate, thiosulfate, elemental sulfur, sulfite, fumarate, nitrate and nitrite were not used as terminal electron acceptors. Strain Ra1766G1T used cellobiose, glucose, mannose, maltose, arabinose, raffinose, galactose, ribose, sucrose, pyruvate and xylose as electron donors. The main fermentation product from glucose metabolism was acetate. The predominant cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0, anteiso DMA-C15 : 0 and C16 : 0. The main polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, iso-DMA-C15 : 0 glycolipids and phospholipids. The G+C content of the genomic DNA was 31.2 mol%. The closest phylogenetic relatives of strain Ra1766G1T were Natranaerovirga pectinivora AP3T (92.4 % 16S rRNA gene sequence similarity), Natranaerovirga hydrolytica APP2T(90.2 %) and Defluviitalea saccharophila 6LT2T (88.9 %). On the basis of phylogenetic inference and phenotypic properties, strain Ra1766G1T represents a novel species of a new genus for which the name Vallitalea guaymasensis is proposed. The type strain of the type species is Ra1766G1T ( = DSM 24848T = JCM17997T).