Proposal of Bacillus ciccensis Liu et al. as a Later Heterotypic Synonym of Cytobacillus solani (Liu et al.) Patel and Gupta Using Comparative Genomic Analysis.

Bacillus ciccensis and Cytobacillus solani were reported to belong to separate genomic species based on a polyphasic taxonomic approach. However, we found that type strains of B. ciccensis and C. solani should belong to the same genomic species based on the clustering patterns resulting from genome phylogenetic analysis. The average nucleotide identity and digital DNA-DNA hybridization values between the genomes of two type strains were 99.6% and 96.9%, respectively, much higher than 95 ~ 96% and 70% cut-off point proposed and generally accepted species boundary. This result was also supported by a comprehensive comparison of phenotypic characteristics between the two type strains. These results suggested that B. ciccensis and C. solani had the same taxonomic position. Consequently, we propose that B. ciccensis is a later heterotypic synonym of C. solani.