Salimicrobium salexigens sp nov., a moderately halophilic bacterium from salted hides

Abstract

Two Gram-positive, moderately halophilic bacteria, designated strains 29CMI(T) and 53CMI, were isolated from salted hides. Both strains were non-motile, strictly aerobic cocci, growing in the presence of 3-25% (w/v) NaCl (optimal growth at 7.5-12.5% [w/v] NaCl), between pH 5.0 and 10.0 (optimal growth at pH 7.5) and at temperatures between 15 and 40 degrees C (optimal growth at 37 degrees C). Phylogenetic analysis based on 16S rRNA gene sequence comparison showed that both strains showed a similarity of 98.7% and were closely related to species of the genus Salimicrobium, within the phylum Firmicutes. Strains 29CMI(T) and 53CMI exhibited 16S rRNA gene sequence similarity values of 97.9-97.6% with Salimicrobium album DSM 20748(T), Salimicrobium halophilum DSM 4771(T), Salimicrobium flavidum ISL-25(T) and Salimicrobium luteum BY-5(T). The DNA G+C content was 50.7 mol% and 51.5 mol% for strains 29CMI(T) and 53CMI, respectively. The DNA-DNA hybridization between both strains was 98%, whereas the values between strain 29CMI(T) and the species S. album CCM 3517(T), S. luteum BY-5(T), S. flavidum ISL-25(T) and S. halophilum CCM 4074(T) were 45%, 28%, 15% and 10%, respectively, showing unequivocally that strains 29CMIT and 53CMI constitute a new genospecies. The major cellular fatty acids were anteiso-C-15:0, anteiso-C-17:0, iso-C-15:0 and iso-C-14:0. The main respiratory isoprenoid quinone was MK-7, although small amounts of MK-6 were also found. The polar lipids of the type strain consist of diphosphatidylglycerol, phosphatidylglycerol, one unidentified phospholipid and one glycolipid. The peptidoglycan type is A1 gamma, with meso-diaminopimelic acid as the diagnostic diamino acid. On the basis of the phylogenetic analysis, and phenotypic, genotypic and chemotaxonomic characteristics, we propose strains 29CMI(T) and 53CMI as a novel species of the genus Salimicrobium, with the name Salimicrobium salexigens sp. nov. The type strain is 29CMI(T) (=CECT 7568(T) = JCM 16414(T) = LMG 25386(T)). (C) 2011 Elsevier GmbH. All rights reserved.