Cloning and characterization of a unique cytotoxic protein parasporin-5 produced by Bacillus thuringiensis A1100 strain.
Cloning and characterization of a unique cytotoxic protein parasporin-5 produced by Bacillus thuringiensis A1100 strain.
复制标题
DOI：
10.3390/toxins6061882
复制
发表时间：
2014-06-18
期刊：
影响因子：
4.2
通讯作者：
Mizuki E
中科院分区：
文献类型：
--
作者：
Ekino K;Okumura S;Ishikawa T;Kitada S;Saitoh H;Akao T;Oka T;Nomura Y;Ohba M;Shin T;Mizuki E
副孢蛋白是存在于非杀虫苏云金芽孢杆菌菌株的伴孢内含物中的杀细胞蛋白，其不具有溶血活性，但具有杀细胞活性，优先杀死癌细胞。在这项研究中，我们表征了属于这一类的杀细胞蛋白，将其命名为副孔蛋白-5（PS5）。从B纯化PS5。苏云金杆菌东北血清变种菌株A1100，基于其对人白血病T细胞（MOLT-4）的杀细胞活性。PS5对MOLT-4细胞的半数有效浓度（EC 50）约为0.075 μg/mL。PS5被表达为一个33.8 kDa的无活性前体蛋白，只有当蛋白酶在C-末端降解成29.8 kDa的小分子时才表现出杀细胞活性。虽然PS5与其他已知的副孢子蛋白没有显着的同源性，位置特异性迭代-基本局部比对搜索工具（PSI-BLAST）搜索显示，该蛋白质显示出轻微的同源性，而不仅仅是一些B。苏云金杆菌Cry毒素，而且气溶素型β-孔形成毒素（β-PFT）。重组PS5蛋白只有在前体中表达，然后用蛋白酶K处理，才能以活性蛋白的形式获得。评价了蛋白质对各种哺乳动物细胞系的细胞毒活性。PS5对18种哺乳动物细胞系中的7种表现出较强的细胞杀伤活性，对其他细胞系的细胞毒性较低或无细胞毒性。
Parasporin is the cytocidal protein present in the parasporal inclusion of the non-insecticidal Bacillus thuringiensis strains, which has no hemolytic activity but has cytocidal activities, preferentially killing cancer cells. In this study, we characterized a cytocidal protein that belongs to this category, which was designated parasporin-5 (PS5). PS5 was purified from B. thuringiensis serovar tohokuensis strain A1100 based on its cytocidal activity against human leukemic T cells (MOLT-4). The 50% effective concentration (EC50) of PS5 to MOLT-4 cells was approximately 0.075 μg/mL. PS5 was expressed as a 33.8-kDa inactive precursor protein and exhibited cytocidal activity only when degraded by protease at the C-terminal into smaller molecules of 29.8 kDa. Although PS5 showed no significant homology with other known parasporins, a Position Specific Iterative-Basic Local Alignment Search Tool (PSI-BLAST) search revealed that the protein showed slight homology to, not only some B. thuringiensis Cry toxins, but also to aerolysin-type β-pore-forming toxins (β-PFTs). The recombinant PS5 protein could be obtained as an active protein only when it was expressed in a precursor followed by processing with proteinase K. The cytotoxic activities of the protein against various mammalian cell lines were evaluated. PS5 showed strong cytocidal activity to seven of 18 mammalian cell lines tested, and low to no cytotoxicity to the others.
登录
查看更多内容
影响因子：
2.7
作者：
Abe, Yuichi;Shimada, Hiroyasu;Kitada, Sakae
通讯作者：
Kitada, Sakae
DOI：
10.1128/cdli.7.4.625-634.2000
发表时间：
2000-07-01
期刊：
CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY
影响因子：
--
作者：
Mizuki, E;Park, YS;Ohba, M
通讯作者：
Ohba, M
影响因子：
4.8
作者：
Ito, A;Sasaguri, Y;Ohba, M
通讯作者：
Ohba, M
影响因子：
3.8
作者：
Hang'ombe, MB;Mukamoto, M;Kozaki, S
通讯作者：
Kozaki, S
影响因子：
2.9
作者：
Nagahama, M;Hara, H;Sakurai, J
通讯作者：
Sakurai, J