Development of nsP2 protease based cell free high throughput screening assay for evaluation of inhibitors against emerging Chikungunya virus

Chikungunya virus has emerged as one of the most important global arboviral threats over the last decade. Inspite of large scale morbidity, with long lasting polyarthralgia, so far no licensed vaccine or antiviral is available. CHIKV nsP2 protease is crucial for processing of viral nonstructural polypeptide precursor to release enzymes required for viral replication, thus making it a promising drug target. In this study, high cell density cultivation (HCDC) of Escherichia coli in batch process was carried out to produce rCHIKV nsP2pro in a cost-effective manner. The purified nsP2pro and fluorogenic peptide substrate have been adapted for fluorescence resonance energy transfer (FRET) based high throughput screening (HTS) assay with Z’ value and CV of 0.67 ± 0.054 and