Chapter 7 Enzymes-Mechanism of Action

《Chapter 7 Enzymes-Mechanism of Action》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、Harper'sIllustratedBiochemistry,30e>CHAPTER7:Enzymes:MechanismofActionPeterJ.Kennelly;VictorW.RodwellINTRODUCTIONOBJECTIVESAfterstudyingthischapter,youshouldbeableto:AppreciateanddescribethestructuralrelationshipsbetweenspecificBvitaminsandcertaincoenzymes.Outlinethef

2、ourprincipalmechanismsbywhichenzymesachievecatalysisandhowthesemechanismscombinetofacilitatecatalysis.Describetheconceptofan“inducedfit”andhowitfacilitatescatalysis.Outlinetheunderlyingprinciplesofenzyme-linkedimmunoassays.Describehowcouplinganenzymetotheactivityofade

3、hydrogenasecansimplifyassayoftheactivityofagivenenzyme.Identifyenzymesandproteinswhoseplasmalevelsareusedforthediagnosisandprognosisofamyocardialinfarction.Describetheapplicationofrestrictionendonucleasesandofrestrictionfragmentlengthpolymorphismsinthedetectionofgenet

4、icdiseases.Illustratetheutilityofsite-directedmutagenesisfortheidentificationofaminoacylresiduesthatareinvolvedintherecognitionofsubstratesorallostericeffectors,orinthemechanismofcatalysis.Describehowtheadditionoffusedaffinity“tags”viarecombinantDNAtechnologycanfacili

5、tatepurificationofaproteinexpressedfromitsclonedgene.Indicatethefunctionofspecificproteasesinthepurificationofaffinity-taggedenzymes.DiscusstheeventsthatledtothediscoverythatRNAscanactasenzymes,andbrieflydescribetheevolutionaryconceptofan“RNAworld.”BIOMEDICALIMPORTANC

6、EEnzymes,whichcatalyzethechemicalreactionsthatmakelifeontheearthpossible,participateinthebreakdownofnutrientstosupplyenergyandchemicalbuildingblocks;theassemblyofthosebuildingblocksintoproteins,DNA,membranes,cells,andtissues;andtheharnessingofenergytopowercellmotility

7、,neuralfunction,andmusclecontraction.Thevastmajorityofenzymesareproteins.NotableexceptionsincluderibosomalRNAsandahandfulofRNAmoleculesimbuedwithendonucleaseornucleotideligaseactivityknowncollectivelyasribozymes.Theabilitytodetectandtoquantifytheactivityofspecificenzy

8、mesinblood,othertissuefluids,orcellextractsprovidesinformationthatcomplementsthephysician’sabilitytodiagnoseandpredictthepro