EXPRESSION OF THE CYTA TOXIN OF BTI IN A CYANOBACTERIUM

蚊子可能是人类已知的最重要的疾病媒介；因此，人们正致力于阐明控制蚊子的新的、有效和安全的方法。这一点尤其重要，因为蚊子污渍的出现对许多常用杀虫剂的抗药性越来越强。苏云金芽孢杆菌亚种杀蚊毒素的应用。以色列杀虫(Bti)是一种极具吸引力的手段，可以显著增加现有的防治药剂，特别是在与其他防治策略结合使用时。BTI毒素对环境是安全的，许多研究表明，它对非目标无脊椎动物和脊椎动物几乎没有毒性。此外，这些毒素的作用水平非常低，在纳克/毫升(Ppm)范围内。遗憾的是，Bti毒素制剂的价格比化学农药高得多，而且在田间的半衰期相对较短，导致应用成本较高。我们建议增加Bti毒素制剂的半衰期，并可能通过在蓝藻细胞中生产毒素来降低生产成本。将利用几种旨在增加蓝藻宿主中毒素表达的方法。此外，我们认为这项工作将对蓝藻中其他有价值的蛋白的表达具有应用价值。拟议的商业应用：除了在野外生产半衰期延长的杀蚊蓝藻菌株外，这项研究还应适用于蓝藻中其他重组蛋白的生产。

Mosquitoes are perhaps the most important disease vectors known to humankind; hence a great deal of effort is directed towards elucidating novel, efficient and safe means to control them. This is particularly important given the advent of mosquito stains which are increasingly resistant to many commonly used insecticides. The use of mosquitocidal toxins produced by Bacillus thuringiensis subsp. israelensis (Bti) is an attractive means of markedly increasing the available repertoire of control agents, particularly when used in concert with other control strategies. Bti toxins are environmentally saf e, as demonstrated in numerous studies, showing virtually no toxicity to non-target invertebrate as well as vertebrate species. In addition, these toxins act at very low levels, in the nanogram/ml (ppm) range. Unfortunately, Bti toxin preparations are considerably more expensive than chemical pesticides and have a relatively short half-life in the field, resulting in higher applications costs. We propose to increase the half life of Bti toxin formulations and possibly lower production costs by producing the toxins within a cyanobacterial cell. Several approaches aimed at increasing toxin expression in a cyanobacterial host will be utilized. In addition, we feel this work will have applications toward the expression of other valuable proteins in cyanobacteria. PROPOSED COMMERCIAL APPLICATION: Beyond producing a mosquitocidal cyanobacterial strain with increased half life in the field, this research should be applicable to the production of other recombinant proteins in cyanobacteria.