简介：BeijinghasbeenoneoftheepicentersattackedmostseverelybytheSARS-CoV(severeacuterespiratorysyndrome-associatedcoronavirus)sincethefirstpatientwasdiagnosedinoneofthecity'shospitals.WenowreportcompletegenomesequencesoftheBJGroup,includingfourisolates(IsolatesBJ01,BJ02,BJ03,andBJ04)oftheSARS-CoV.ItisremarkablethatallmembersoftheBJGroupshareacommonhaplotype,consistingofsevenlocithatdifferentiatethegroupfromotherisolatespublishedtodate.Among42substitutionsuniquelyidentifledfromtheBJgroup,32arenon-synonymouschangesattheaminoacidlevel.Rootedphylogenetictrees,proposedonthebasisofhaplotypesandothersequencevariationsofSARS-CoVisolatesfromCanada,USA,Singapore,andChina,gaverisetodifferentparadigmsbutpositionedtheBJGroup,togetherwiththenewlydiscoveredGD01(GD-Ins29)inthesameclade,followedbytheH-UGroup(fromHongKongtoUSA)andtheH-TGroup(fromHongKongtoToronto),leavingtheSPGroup(Singapore)moredistant.ThisresultappearstosuggestapossibletransmissionpathfromGuangdongtoBeijing/HongKong,thentoothercountriesandregions.

简介：TheR(replicase)proteinistheuniquelydefinednon-structuralprotein(NSP)responsibleforRNAreplication,mutationrateorfidelity,regulationoftranscrip-tionincoronavirusesandmanyotherssRNAviruses.Basedonourcompletegenomesequencesoffourisolates(BJ01-BJ04)ofSARS-CoVfromBeijing,China,weanalyzedthestructureandpredictedfunctionsoftheRproteinincomparisonwith13otherisolatesofSARS-CoVand6othercoronaviruses.TheentireORF(open-readingframe)encodesfortwomajorenzymeactivities,RNA-dependentRNApolymerase(RdRp)andproteinaseactivities.TheRpolyproteinunder-goesacomplexproteolyticprocesstoproduce15function-relatedpeptides.Ahydrophobicdomain(HOD)andahydrophilicdomain(HID)arenewlyidentifiedwithinNSP1.ThesubstitutionrateoftheRproteinisclosetotheaverageoftheSARS-CoVgenome.ThefunctionaldomainsinallNSPsoftheRproteingivedifferentphylogeneticresultsthatsuggesttheirdifferentmutationrateunderselectivepressure.ElevenhighlyconservedregionsinRdRpandtwelvecleavagesitesby3CLP(chymotrypsin-likeprotein)havebeenidentifiedaspotentialdrugtargets.Findingssuggestthatitispossibletoobtaininformationaboutthephy-logenyofSARS-CoV,aswellaspotentialtoolsfordrugdesign,genotypinganddiagnosticsofSARS.

简介：Purifiedproteinderivative(PPD)skintestsoftenyieldpoorspecificity,sothattodevelopnewserologicalantigensfordistinguishingbetweenMycobacteriumtuberculosisinfectionandBacilleCalmette-Guerin(BCG)vaccinationisapriority,especiallyfordevelopingcountrieslikeChina.Wepredictedtheantigenicityforselectedopenreadingframes(ORFs)basedonthegenomesequencesofM.tuberculosisH37RvandM.bovisBCG,aswellastheirfunctionsanddifferencesofexpressionunderdifferentstimulus.ThecandidateORFswereclonedfromH37RvsequencesandexpressedasrecombinantproteinsinEscherichiacoli.Westudiedtheserodiagnosticpotentialof11purifiedrecombinantsbyusingenzyme-linkedimmunosorbentassay(ELISA)andinvolvingacohortcomposedof58TBpatients(34malesand24females),8healthyvolunteersand50PPD-negativeindividualsbeforeandafterBCGvaccination.Forallthe11antigens,themedianODvaluesfortheserafromTBpatientswerestatisticallysignificantlyhigherthanthoseforPPD-negativeindividualsbeforeorafterBCGvaccination(P<0.01).Theyhadatleast92%specificityinhealthycontrolsandsixseroantigens(Rv0251c,Rv1973,Rv2376c,Rv2537c,Rv2785candRv3873A)wereneverreportedwithseroantigenicitiespreviously.Thustheapproachcombiningcomparativegenomics,bioinformaticsandELISAtechniquescanbeemployedtoidentifynewseroantigensdistinguishingM.tuberculosisinfectionfromBCGvaccination.