Theoretical 3d modelling of a novel Cry toxin isolated from native Bacillus thuringiensis isolate sk711 Panwar Bhupendra Singh, Narula Rakesh Kumar, Kaur Sarvjeet* ICAR-National Research Centre on Plant Biotechnology, New Delhi, 110012 *Corresponding author Email: dr_sarvjeetkaur@yahoo.com
Online published on 13 March, 2018. Abstract The cry genes synthesized by Bacillus thuringiensis (Bt) during sporulation are a valuable source for the substitution of chemical pesticides. Exploration and evaluation of Bt toxins via novel gene isolation, DNA shuffling and in silico characterization are emerging as promising tools for the development of novel Bt toxins. In the current investigation, we isolated and structurally characterized a new cry gene from Indian Bt isolate, SK711. Furthermore, the theoretical three dimensional structure of a novel delta endotoxin belonging to the three domain Cry toxin family has been investigated through comparative homologous modelling. The refined model was evaluated by RAMPAGE, ERRAT and Verify 3D. Despite of its low sequence identity to the previously reported Cry protein structure, it not only resembles, but also shares five common conserved blocks of amino acid residues. This result is expected to be valuable in protein engineering and will serve as a starting point for the designing of experiment involving mutagenesis and bioassay aimed at the improvement of toxicity. Top Keywords Bacillus thuringiensis, Cry gene, SK711, ip7 gene, isolation, structural characterisation, 3D modelling, low sequence, protein engineering, cloning, sequencing. Top |