khypothesizedthatDNAreplicatesitselfby"unzipping"alongthehydrogenbondsjoiningAtoTandCtoG.plementarystrands.Thismodelofsemiconservativereplicationconservativebecauseeachnewmoleculehasonehalfoftheformerparentmolecule-waslaterconfirmedbytheworkofDNA进行复制是以拉链方式自我复制,产生的两个二分体分别为模板生成互补链,即半保留复制。并由Meselson和Stahl验证。InE.coliDNAreplicationbeginswiththeformationofabubblelikestructureonthecircularchromosomethatisproducedbyreplicationforks.StudiesofbacterialDNAreplicationhaveshownthatagrowingDNAchainlengthensonlyinthe5'to3'direction(fromthe5'carbonofonesugartothe3'carbonofthenext).Theleadingstrandissynthesizedcontinuously,whilethelaggingstrandissynthesizedinshortstretchesknownasOkazakifragments.TheenzymeDNApolymeraselinksfreenucleotidesastheylineuponthetemplateformedbytheoriginalstrandoftheparentmolecule.
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