Unit of Microbiology and Molecular Biology, Vector Control Research Centre, Indian Council of Medical Research (ICMR), Puducherry, 605 006, India.
Biomedical Informatics Centre, Vector Control Research Centre, Indian Council of Medical Research (ICMR), Puducherry, 605 006, India.
World J Microbiol Biotechnol. 2018 Jul 12;34(8):116. doi: 10.1007/s11274-018-2498-4.
A strain of Bacillus amyloliquefaciens (VCRC B483) exhibiting mosquito pupicidal, keratinase and antimicrobial activities was isolated from mangrove forest ecosystem of Andaman and Nicobar Islands. Molecular characterization of the strain showed the presence of lipopeptide encoding bmyC gene. Phylogenetic tree based on protein sequence of this gene exhibited homology with mycosubtilin synthetase of Bacilus atropheus and Iturin synthetase of Bacillus subtilis and B. amyloliquefaciens. This is the first report on the evolutionary conservation of amino acids concerned with the function and structure of bmyC protein of B. amyloliquefaciens. The presence of valine at the 1197th position in our strain was found to be unique and different from the existing strains of B. subtilis and B. amyloliquefaciens. Molecular modelling studies revealed significant changes in the structure of epimerization domain of the bmyC protein with A1197V variation. Crude metabolite of this strain exhibited antifungal activity against Fusarium sp. and Carvularia sp.
从安达曼和尼科巴群岛的红树林生态系统中分离到一株具有杀蚊幼虫、角蛋白酶和抗菌活性的解淀粉芽孢杆菌（VCRC B483）。该菌株的分子特征表明存在编码 bmyC 基因的脂肽。基于该基因的蛋白质序列构建的系统发育树与枯草芽孢杆菌的 mycosubtilin 合成酶和枯草芽孢杆菌和解淀粉芽孢杆菌的iturin 合成酶具有同源性。这是首次报道与解淀粉芽孢杆菌 bmyC 蛋白的功能和结构相关的氨基酸的进化保守性。我们菌株在 1197 位上的缬氨酸的存在是独特的，与现有的枯草芽孢杆菌和解淀粉芽孢杆菌菌株不同。分子建模研究表明，bmyC 蛋白的差向异构酶结构域结构发生了显著变化，A1197V 发生了变异。该菌株的粗代谢产物对镰刀菌属和 Carvularia 属具有抗真菌活性。
