Bacillus ciccensis sp. nov., isolated from maize (Zea mays L.) seeds

Abstract

Two Gram-stain-positive bacterial strains, designated as 5L6T and 6L6, isolated from seeds of hybrid maize (Zea mays L., Jingke 968) were investigated using a polyphasic taxonomic approach. The cells were aerobic, motile, endospore-forming and rod-shaped. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolates were recognized as a species of the genus Bacillus, to which the five closest neighbours are Bacillus solani FJAT-18043T (99.8% similarity), Bacillus horneckiae DSM 23495T (97.7%), Bacillus eiseniae A1-2T (97.4%), Bacillus kochii WCC 4582T (97.1%) and Bacillus purgationiresistens DS22T (97.0%). The DNA G+C content of strain 5L6T was 37.4 mol%. Its polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant respiratory quinone was MK-7 and the major fatty acids were iso-C15: 0, anteiso-C15: 0, iso-C16: 0, iso-C14: 0, anteiso-C17: 0 and C16: 1 ω7c alcohol. The cell-wall peptidoglycan contained ornithine, serine, aspartic acid, glutamic acid and alanine while diaminopimelic acid could not be detected. Strains 5L6T and 6L6 were clearly distinguished from the type strains of related validly named species using phylogenetic analysis, DNA？DNA hybridization, fatty acid analysis, peptidoglycan analysis and comparison of a range of physiological and biochemical characteristics. The genotypic and phenotypic data show that strains 5L6T and 6L6 represent a novel species of the genus Bacillus, for which the name Bacillus ciccensis sp. nov. is proposed. The type strain is 5L6T (=KCTC 33663T=CICC 23855T=DSM 104513T).