Prediction of the three-dimensional structure of serine/threonine protein kinase pto of Solanum lycopersicum by homology modelling

The resistant gene Pto of Solanum lycopersicum interacts with the avr Pto gene product of the bacterial pathogen Pseudomonas syringae pv tomato to launch a cascade of molecular events that triggers the hypersensitive disease-resistance response in tamato. The paper describes attempts to predict the structure of Pto encoding a serine/threonine protein kinase to understand the mechanism and function. A three-dimensional model based on the crystal structure of effect protein Avr ptob complexed with Kinase Pto and bacterial effector protein Avrpto was generated using Modeller9v7. We adopted different modelling approaches for our study, Intialy, we generated a model based on a single template protein and then a model based on multiple templates. The models generated through these approaches were further assessed with ANOLEA energy assessment, Ram Page server and PROCHECK for stereochemistry and geometry check. Comparative analysis suggested that the model generated was better than the templates. This study paves the way for generating computer molecular models for proteins whose crystal structures are not available and which would aid in studying protein-protein interactions.