关键词: BS2, 生物信息学分析, 转基因烟草, 黄萎病抗性

Abstract: BS2 protein is derived from Bacillus subtilis B111 with strong resistance to Verticillium wilt. It can inhibit the spore germination of Verticillium dahliae and destroy its mycelial growth. The full length of BS2 gene is 1 566 bp, and it has 522 codons. Because of the difference of preferred codons,  if it is directly introduced into plants without optimization it will result in low or no expression of genes. The BS2 was optimized according to plant optimal synthesis, and 332 codons were optimized. The bioinformatics analysis showed that 1～28 amino acids composed a N-terminal signal peptide ; the mature BS2 protein was composed of amino acids 224～521 and was a neutral zinc metal peptidase. The subcellular localization maped the BS2 protein to the cell membrane. By Oxford Cup method,  the crude protein extract of transgenic tobacco lines showed strong antibacterial activity. It was founded that the  control group without infestation of Verticillium dahliae, the growth of the wild type and transgenic plants was basically the same, the phenotype was not significantly different, while under infection group of Verticillium dahliae V991, the phenotypic traits of transgenic tobacco were significantly better than wild type, the activity of SOD, CAT and content of SA, ABA in transgenic tobacco were higher than those in wild type tobacco. So, the BS2 gene could significantly improve the resistance of transgenic tobacco to Verticillium wilt.

Key words: BS2, bioinformatics analysis, transgenic tobacco, resistance to Verticillium wilt