Structure-based Drug Design Targeting Enterovirus 71 3C^proand Coxsackievirus B3 3D^pol

The structure-based design of inhibitors in this thesis is comprised of two parts targeting 1)3C protease from enterovirus 71,and 2)3D polymerase from Coxsachivirus B3.1)Hand-foot-mouth disease(HFMD)is a global infectious diseases caused by enteroviruses.In recent years,its morbidity in China has increased significantly.Among the causative agents of HFMD,enterovirus 71(EV71)is the main one.This virus can lead to serious neurological complications,and even lead to death.It is of great importance to find treatment for HFMD.3C protease plays a key role in the maturation of EV71 proteins.3C protease can also act on a variety of transcription factors and cytokines in host cells,inhibit the expression of host protein and interfere with the immune mechanisms of the host.In addition,3C protease is with RNA binding activity and play a role in virus replication.3C protease is a significant target for the design and development of therapeutics.In this project,we screened a drug library with 3C protease as the target.The complex structures of 3C protease and small molecule fragments were analyzed by X-ray crystallography and a compound bound to the RNA binding region of 3C protease was identified,which laid the foundation for the fragment-based drug design.2)Viral myocarditis is caused by viruses that can damage myocardium.Currently,domestic VMC mortality rates were on the rise.Among the enterovirus,Coxsackievirus B3 is an important pathogen in viral myocarditis.CVB3 can also induce the injury or death of human pancreatic islet ?-cells,and it is thought to be associated with type I adolescent diabetes or insulin-independent diabetes mellitus.3Dpol is an RNA-dependent RNA polymerase(RdRP)and vital to the life cycle of the RNA virus.3Dpol is responsible for the initial negative and subsequent positive strand RNA synthesis,and is important to the viral replication and viability.The 3Dpol inhibitors can inhibit the viral genome and viral replication and is a significant target for the development of antiviral drugs.To establish a system for structure-based drug design and development,we used technologies of molecular cloning,protein expression and purification to obtain the proteins and the crystals of 3Dpol were made.However,only a small portion of the crystals diffracted X-ray to high resolution.Further optimization was needed to crystallize 3Dpol in a consistent fashion for the drug design and development.