title: Genetic and genomic diversity of NheABC locus from Bacillus strains.
abstract: Non-hemolytic enterotoxin (NHE), a tri-partite, proteinaceous toxin encoded by contiguous nheA, nheB and nheC genes of Bacillus cereus sensu lato (B. cereus s.l.), is considered to be associated with the foodborne diarrheic syndrome. However, B. cereus s.l. includes a number of closely related strains, and the occurrence of NHE among them, and other members of Bacillus is unclear. Consequently, we aimed to determine the distribution and evolution of NHE within Bacillus by confirming the presence of the nheA, B and C sequences and variation within them using published data, and to analyze the genomic and genetic diversity. The phylogenetic tree of NHE proteins (NheA, NheB and NheC) from 81 different B. cereus s.l. strains was constructed. And on the genetic determinants of the NHE toxin did not bring any obvious link between the nheABC genes sequence of a strain and its virulence in the diarrhoeal pathogenesis. Analysis of the genomic diversity of the nheA, B and C loci revealed that their upstream regions were more conserved than the downstream sequences. Multilocus sequence typing schemes (MLST) based on seven concatenated housekeeping genes and nheA, B and C genes of the 75 strains were developed. The neighbor joining phylogenetic tree based on seven housekeeping genes together with nheA, B and C genes was similiar to published Bacillus phylogenetic trees. And on the genetic determinants of the NHE toxin did not bring any obvious link between the nheABC genes sequence of a strain and its virulence in the diarrhoeal pathogenesis.The results indicate that nheA, B and C genes do not affect the diversity of housekeeping genes, and this specific NHE protein does not participate in the diarrheic syndrome.
authors.affiliation: School of Food Science and Technology, Changzhou University, No.1# Gehu Middle Road, Changzhou, 213164, Jiangsu, People's Republic of China.
authors.forename: Yan
authors.identifier: http://orcid.org/0000-0003-1014-1547
authors.initials: Y
authors.lastname: Cai
authors.affiliation: School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, People's Republic of China.
authors.forename: Tingxuan
authors.initials: T
authors.lastname: Huang
authors.affiliation: College of Life Science, Anhui Normal University, No.1# Beijing East Road, Wuhu, 241002, Anhui, People's Republic of China.
authors.forename: Yuekang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, 430023, People's Republic of China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Zhou
authors.affiliation: School of Food Science and Technology, Changzhou University, No.1# Gehu Middle Road, Changzhou, 213164, Jiangsu, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Zou
authors.affiliation: School of Food Science and Technology, Changzhou University, No.1# Gehu Middle Road, Changzhou, 213164, Jiangsu, People's Republic of China.
authors.forename: Guifeng
authors.initials: G
authors.lastname: Zeng
authors.affiliation: College of Life Science, Anhui Normal University, No.1# Beijing East Road, Wuhu, 241002, Anhui, People's Republic of China. liuxiaojin3@foxmail.com.
authors.forename: Xiaojin
authors.initials: X
authors.lastname: Liu
mesh_terms: D001409:Bacillus cereus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics*; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics*; D004768:Enterotoxins / Q000096:biosynthesis / Q000235:genetics*; D005517:Foodborne Diseases / Q000382:microbiology; D006801:Humans; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D037521:Virulence Factors / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004768:Enterotoxins; C000589183:NheA protein, Bacillus cereus; D037521:Virulence Factors
keywords: Bacillus; Genetic diversity; MLST; NheABC