Screening Of Peptides Binding To Foot-and-mouth Disease Virus By Phage Display Technology

Foot-and-mouth disease is a potent infectious disease caused by the food-and-mouth disease virus(FMDV).It is one of the most important pathogens that harm the swine industry.FMDV belongs to the small RNA virus family in the virological classification,and its genetic material is a single strand of positive strand RNA.There are seven serotypes known as O-type,A-type,C-type,SAT1 type,SAT2 type,SAT3 type,and Asia I type.The prevalence of foot-and-mouth disease in various regions is very different.Therefore,a full-scale quarantine inspection must be carried out to prevent epidemics and prevent the inflow of contaminated live animals or livestock products in other areas.Foot-and-mouth disease mainly causes the onset of major meat animals such as cattle,sheep,and pigs.It is highly infectious and poses a great threat to the aquaculture industry in all countries.It not only causes huge economic losses,but also causes adverse political impact.It is not conducive to national friendly trade relations.The Office International Des Epizooties(OIE)lists it as a Class A animal infectious disease and is the first of a class of infectious diseases in China.Due to the low homology between the FMDV serotypes and the rapidity of mutation,it has been raging for many years worldwide,and only a few countries have claimed to be “Foot-and-Foot-Fighting Countries”.The main distribution area of foot-and-mouth disease in China is distributed in the marginal areas of the south.To detect and control the outbreak early,the development of faster and more accurate quarantine methods has always been a goal pursued by researchers.Phage display technology has the advantages of wide range of peptide libraries,simple screening procedures,and rapid screening efficiency,and is particularly suitable for short acting peptides.Phage display technology has achieved good results in the infection of human diseases such as HIV,hepatitis B virus(HBV),and laid a foundation for the study of viral affinity peptides.Screening peptides that can highly bind to viral coat proteins or epitopes provides a theoretical basis for the development of novel detection methods and vaccine preparation.This experiment aims to use purified virions as target molecules and use phage display technology to screen out peptide sequences that can specifically bind to FMDV,laying the foundation for the development of novel detection technologies or peptide drugs.A total of four rounds of screening were conducted during the experiment,and the screening conditions became increasingly stringent,making the resulting phage more binding,a total of 4 differential sequences were obtained.The selected phage were further identified by ELISA,Dot-Blot experiments,and finally 3 high affinity phage clones were obtained.The three phage monoclonal DNAs were rapidly purified and the peptide sequences were obtained by translation.The peptides were uploaded to the APD3 database for prediction of the solubility and static charge of the peptides,which were then sent to the company for chemical synthesis.A peptide T1 specifically bound to FMDV was screened by experiments and it was known that the target protein bound by T1 and FMDV was VP1.High-purity proteins can be obtained,providing experimental basis and theoretical basis for further directed disease evolution,such as the detection and treatment of diseases and the development of vaccines.