Description of Fervidibacillus gen. nov. in the family Fervidibacillaceae fam. nov. with two species, Fervidibacillus albus sp nov., and Fervidibacillus halotolerans sp nov., isolated from tidal flat

Abstract

Two Gram-stain-positive, motile, endospore-forming, facultatively anaerobic strains, designated MEBiC13591T and MEBiC13594T, were isolated from tidal flat sediment of the Incheon City, West seaside of Korea. 16S rRNA gene sequence analysis revealed that the novel strains were affiliated to the genus Bacillus, a member of the Fervidibacillaceae, showing sequence similarities of 96.1-96.3% with the type strain of Bacillus kwashiorkori. Growth was observed at pH 5–9 (optimum, pH 7.5) for strain MEBiC13591T, and pH 5–9 (pH 7) for strain MEBiC13594 T. Both strains displayed growth in 0–8 % NaCl with an optimum at 2% for strain MEBiC13591T and 3 % for strain MEBiC13594T. Strains MEBiC13591T and MEBiC13594T grew optimally at 49.8 °C, (37.5-56.1 °C) and 43.8 °C (20.7-50.7 °C), respectively. The main cellular fatty acids of strain MEBiC13591T were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, iso-C17 : 0 and anteiso-C17 : 0, while those of strain MEBiC13594T were C14 : 0, iso-C14 : 0, iso-C15 : 0, anteiso-C15 : 0 and C16 : 0. In Both cases, the major isoprenoid was MK-7. DNA G+C contents were 35.4 and 36.5 mol% for MEBiC13591T and MEBiC13594T, respectively. Based on the phenotypic, genomic and biochemical data, strains MEBiC13591T and MEBiC13594T represent two novel species in the genus Bacillus for which the names Fervidibacillus albus sp. nov. [MEBiC13591T (=KCCM 43317 T =JCM 33662 T)], and Fervidibacillus halotolerans sp. nov. [MEBiC13594T (=KCTC 43182T =MCCC 1K06222T)] are proposed. [Supported grants from KIOST & MBRB].