[ Objective] This study aimed to clone and identify enterocin gene from Enterococcus. [ Method] The genomic DNA of 12 enterocecci was extracted, and separately amplified with specific primers. The amplified fragments ...[ Objective] This study aimed to clone and identify enterocin gene from Enterococcus. [ Method] The genomic DNA of 12 enterocecci was extracted, and separately amplified with specific primers. The amplified fragments were ligated into PGEM-T Easy vector, which was then transformed into DH5α competent cells. The positive clones were sequenced. [Result] Enterocin A gene was 274 bp long. It was obtained from six enterococci, and the amino acids encoded by the enterocin genes cloned from five object enterocecci were the same as that of type IIa reference strains except only one amino acid. The homology among them reached 99.76 - 100%, suggesting that the bacteriocin isolated from the enterococcis belonged to type II. Structure prediction by DNAstar indicated that 22nd - 30th amino acids of enterocin A formed ot region, which had a hydrophilic region at its N-terminal and a hydrophobic region at its C-terminal, a transmembrane helix structure. [ Conclusion] This study will provide basis for the heterologous expression and applications of enterocins. Key words Enterocin gene; Enterocecci; PCR; Sequence analysis展开更多
基金Supported by General Project of Beijing Municipal Education Commissiona grant from the Schoolboard of Beijing,China(KM201110020005)
文摘[ Objective] This study aimed to clone and identify enterocin gene from Enterococcus. [ Method] The genomic DNA of 12 enterocecci was extracted, and separately amplified with specific primers. The amplified fragments were ligated into PGEM-T Easy vector, which was then transformed into DH5α competent cells. The positive clones were sequenced. [Result] Enterocin A gene was 274 bp long. It was obtained from six enterococci, and the amino acids encoded by the enterocin genes cloned from five object enterocecci were the same as that of type IIa reference strains except only one amino acid. The homology among them reached 99.76 - 100%, suggesting that the bacteriocin isolated from the enterococcis belonged to type II. Structure prediction by DNAstar indicated that 22nd - 30th amino acids of enterocin A formed ot region, which had a hydrophilic region at its N-terminal and a hydrophobic region at its C-terminal, a transmembrane helix structure. [ Conclusion] This study will provide basis for the heterologous expression and applications of enterocins. Key words Enterocin gene; Enterocecci; PCR; Sequence analysis
