A novel bacterium, designed strain S38T, was isolated from the deep-sea sediment of Pacmanus hydrothermal field in Manus Basin. The isolate was gram-positive, aerobic, motile, and was defined by endospore-forming rods. Strain S38T grew at 16-38 °C, pH 6-8, and in the presence of 0-7% (w/v) NaCl. Based on 16S rRNA gene sequence, S38T was grouped into the genus Fictibacillus and was most closely related to Fictibacillus phosphorivorans CCM 8426T (97.8%), Fictibacillus nanhaiensis DSM 23009T (97.8%), Fictibacillus halophilus DSM 100124T (97.7%), and Fictibacillus barbaricus DSM 14730T (97.5%). The diagnostic diamino acid of the cell wall was meso-diaminopimelic acid. The major fatty acids were iso-C15:0 and anteiso-C15:0. MK-7 was the predominant respiratory quinone and diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine were the major polar lipids. The genomic DNA G + C content was 46.8 mol%. Phylogenetic analysis, DNA-DNA relatedness, and phenotypic characteristics supported that strain S38T represents a novel species within the genus Fictibacillus, for which the name Fictibacillus iocasae sp. nov. was proposed. The type strain is S38T (= KCTC 33865T = DSM 104298T = CGMCC 1.16031T).
Keywords: Chemotaxonomic characterization; Fictibacillus iocasae; Hydrothermal sediment; Type strain.