Parasporin-2Ab, a newly isolated cytotoxic crystal protein from Bacillus thuringiensis
Parasporin-2Ab, a newly isolated cytotoxic crystal protein from Bacillus thuringiensis
复制标题
DOI：
10.1007/s00284-006-0351-8
复制
发表时间：
2007-10-01
影响因子：
2.6
通讯作者：
Sakai, Hiroshi
中科院分区：
文献类型：
--
作者：
Hayakawa, Tohru;Kanagawa, Rie;Sakai, Hiroshi
从苏云金芽孢杆菌TK-E6菌株中克隆了一种新的晶体蛋白，该蛋白对人白血病T细胞具有强的细胞毒性。该蛋白命名为parasporin-2Ab（PS2 Ab），是一种由304个氨基酸残基组成的多肽，预测分子量为33，017。推导的氨基酸序列与来源于B的parasporin-2Aa（PS2 Aa）有84%的同源性。苏云金杆菌A1547菌株。在用蛋白酶K处理PS2 Ab后，产生29 kDa的活性形式。活化的PS2 Ab对MOLT-4和Jurkat细胞显示出强的细胞毒性，并且EC 50值分别估计为0.545和0.745 ng/mL。PS2 Ab的细胞毒性明显高于其他文献报道的PS2 Aa。尽管两种细胞毒素在结构上相关，但认为发现的微小差异是PS2 Ab和PS2 Aa的不同细胞毒性的原因。
A novel crystal protein that exhibited potent cytotoxicity against human leukemic T-cells was cloned from the Bacillus thuringiensis TK-E6 strain. The protein, designated as parasporin-2Ab (PS2Ab), was a polypeptide of 304 amino acid residues with a predicted molecular weight of 33,017. The deduced amino acid sequence of PS2Ab showed significant homology (84% identitiy) to parasporin-2Aa (PS2Aa) from the B. thuringiensis A1547 strain. Upon processing of PS2Ab with proteinase K, the active form of 29 kDa was produced. The activated PS2Ab showed potent cytotoxicity against MOLT-4 and Jurkat cells and the EC50 values were estimated as 0.545 and 0.745 ng/mL, respectively. The cytotoxicity of PS2Ab was significantly higher than that of PS2Aa reported elsewhere. Although both cytotoxins were structurally related, it was thought that the minor differences found were responsible for the different cytotoxicities of PS2Ab and PS2Aa.