Heterologous expression and in-silico characterization of Pathogenesis related protein1 (CsPR1) gene from Camellia sinensis.

Pathogenesis related protein1 gene induced after pathogen infection in plants have been frequently used as marker gene for systemic acquired resistance. We have carried out isolation, annotation and expression of CsPR1, a potential disease resistance gene. The full length cDNA consist of 671 bp in length containing 162 amino acids with a signal peptide of 22 amino acids and 17.92 kDa predicted molecular weight. Recombinant CsPR1 was successfully expressed in BL21(DE3)pLysS cells using pET 43.1 EK LIC vector system and was purified. Three dimensional models were generated using Phyre2 and I-TASSER and built a compact structure consisting beta sheets surrounded by alpha helixes. The models were validated by MolProbity and RAMPAGE servers. Validation of modelled structures based on Ramachandran plot, revealed I-TASSER produce better quality and reliable 3D model. Purified recombinant CsPR1 and in silico generated 3D models from this study provide foundation for comprehensive functional and structural characterization of CsPR1 protein.