Arora Naresh, Sachdev Bindiya, Gupta Rani, Vimala Y, Bhatnagar Raj K
International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India.
PLoS One. 2013 Jun 18;8(6):e66603. doi: 10.1371/journal.pone.0066603. Print 2013.
Strains of Bacillus thuringiensis produce insecticidal proteins. These strains have been isolated from diverse ecological niches, such as soil, phylloplane, insect cadavers and grain dust. To effectively propagate, these strains produce a range of molecules that facilitate its multiplication in a competing environment. In this report, we have examined synthesis of a chitin-binding protein and evaluated its effect on fungi encountered in environment and its interaction with insecticidal proteins synthesized by B. thuringiensis. The gene encoding chitin-binding protein has been cloned and expressed. The purified protein has been demonstrated to interact with Cry insecticidal protein, Cry1Ac by Circular Dichrosim spectroscopy (CD) and in vitro pull down assays. The chitin-binding protein potentiates insecticidal activity of bacillar insecticidal protein, Cry1Ac. Further, chitin-binding protein was fungistatic against several soil fungi. The chitin binding protein is expressed in spore mother cell and deposited along with insecticidal protein, Cry1Ac. It interacts with Cry1Ac to potentiate its insecticidal activity and facilitate propagation of Bacillus strain in environment by inhibiting growth of certain fungi.
苏云金芽孢杆菌菌株可产生杀虫蛋白。这些菌株已从不同的生态位中分离出来，如土壤、叶表面、昆虫尸体和谷物粉尘。为了有效繁殖，这些菌株会产生一系列分子，以促进其在竞争环境中的增殖。在本报告中，我们研究了一种几丁质结合蛋白的合成，并评估了其对环境中所遇到真菌的影响以及它与苏云金芽孢杆菌合成的杀虫蛋白之间的相互作用。编码几丁质结合蛋白的基因已被克隆并表达。通过圆二色光谱（CD）和体外下拉实验已证明纯化后的蛋白可与Cry杀虫蛋白Cry1Ac相互作用。几丁质结合蛋白可增强芽孢杆菌杀虫蛋白Cry1Ac的杀虫活性。此外，几丁质结合蛋白对几种土壤真菌具有抑菌作用。几丁质结合蛋白在孢子母细胞中表达，并与杀虫蛋白Cry1Ac一起沉积。它与Cry1Ac相互作用以增强其杀虫活性，并通过抑制某些真菌的生长来促进芽孢杆菌菌株在环境中的繁殖。
