InordertodevelopclinicaldiagnostictoolsforrapiddetectionofSARS-CoV(severeacuterespiratorysyndrome-associatedcoronavirus)andtoidentifycandidateproteinsforvaccinedevelopment,theC-terminalportionofthenucleocapsid(NC)genewasamplifiedusingRT-PCRfromtheSARS-CoVgenome,clonedintoayeastexpressionvector(pEGH),andexpressedasaglutathioneS-transferase(GST)andHisx6double-taggedfusionproteinunderthecontrolofaninduciblepromoter.WesternanalysisonthepurifiedproteinconfirmedtheexpressionandpurificationoftheNCfusionproteinsfromyeast.Todetermineitsantigenicity,thefusionproteinwaschallengedwithserumsamplesfromSARSpatientsandnormalcontrols.TheNCfusionproteindemonstratedhighantigenicitywithhighspecificity,andtherefore,itshouldhavegreatpotentialindesigningclinicaldiagnostictoolsandprovideusefulinformationforvaccinedevelopment.