A Gram-stain-positive, non-motile, endospore-forming, rod-shaped and aerobic bacterium was isolated from surface-sterilized branch of Aegiceras corniculatum in Guangxi Zhuang Autonomous Region, China. The isolate, designated strain 165T, grew at 20-45 °C (optimum, 30 °C), pH 6.0-7.0 (optimum, 6.0) and with 0-3 % (w/v) NaCl (optimum, 1 %). The major respiratory quinone was MK-7 and the cell-wall peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and an unidentified glycolipid. The major fatty acids were iso-C15:0, anteiso-C15:0 and iso-C16:0. On the basis of 16 S rRNA gene sequence and multiple genes of conserved core proteins analysis, strain 165T was a member of the genus Ectobacillus. Its closest phylogenetic neighbor was Ectobacillus panaciterrae Gsoil 1517T, with sequence similarity of 97.1 %. The average nucleotide identity value between strain 165T and type strain of Ectobacillus panaciterrae was 73.0 %. The estimated DDH value between strain 165T and type strain of Ectobacillus panaciterrae was 19.7 %. The genome of strain 165T was 3, 545, 051 bp long with a DNA G + C content of 38.2 % and encodes 3459 predicted proteins, 25 rRNAs, 87 tRNAs and 5 ncRNA. The genome of strain 165T comprised gene clusters of type 3 PKS, terpene, betalactone and lanthipeptide-class-ii for secondary metabolites. Phenotypic, chemotaxonomic and phylogenetic analyses supported the strain 165T as a representative of a novel species of the genus Ectobacillus, for which the name Ectobacillus aegiceratis sp. nov. is proposed, with strain 165T (= JCM 33,414T = CGMCC 1.13742T) as the type strain.
Keywords: Bacterium; Ectobacillus aegiceratis; Novel species; Polyphasic approach.
© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.