udywasbasedontwohbvstraiwithdifferentreplicativeefficiency,whichwereisolatedseparatelyfromtheseraoftwopatientswithchronichepatitis.strategiestogeneratechimericgenomebypolymerasechainreactionandsite-directedmutagenesiswereemployedforcharacterizationofthefunctionaldomainreoiblefordifferentreplicationcompetencebetweenthesetwohbvstrai.resultsshowedthatasingleaminoacidsutitutionfromserinetoprolineinposition652withinthertregionofpolymerasegenewasreoibleforsuchstrikingdifferencebetweenthesetwohbvstrai.mo
reover,threedimeionalanalysisofrtregionofhbvpolymeraseshowedthataminoacidsutitutionfromprolinetoserineinposition652couldimpairthepolymeraseactivity.therefore,the652aminoacidinthepolymeraseproteinisanewlyidentifiedfunctionalsiteaociatedwithenhancedreplication.thisfindingcanbeusedtodevelopnewanti-hbvtherapeuticsdrugs.
inthesecondpartofthisstudy,full-lengthhbvgenomeswerecollectedfromhepatocellularcarcinoma(hcc)tiuestostudytheirreplicativeefficiency.whenisolateswerecollectedfromapatientwhowasanhagpositiveasymptomaticcarrierwhodevelopedhccinfouryears,itwasshowedthatfull-lengthhbvisolatedfromthelivertiuesofhccpatientsexhibitedhigherreplicativecompetencethanthosefromtheserasamples.inaddition,itwasalsoshowedthat2.2kblicingvariantsofhbvinlivertiuescouldenhancetherepliationofitsfull-lengthcounterpart.bothenhancedreplicationoffull-lengthhbvandthe2.2kblicingvariantsmightcontributetothepersistenceofhbvinfectionwhichcouldbeoneofthefactorsinvolvedinthehighincidenceofhepatocellularcarc