MatrixInnermembraneOutermembraneIntermembranespaceFigure14-8part2of3.MolecularBiologyoftheCell,4thEdition.100nmFigure14-8part1of3.MolecularBiologyoftheCell,4thEdition.Textbook EM and cartoons of mitochondria. Mitochondria havetwo membrane--inner and outer, and two compartments--matrixandinnermembranespace11
Textbook EM and cartoons of mitochondria. Mitochondria have two membrane-inner and outer, and two compartments-matrix and inner membrane space. 11
ATPsynthaseOuter membrane(F.F.)Outer membrane.Because it contains a large channel-forming protein (calledporin),theoutermembraneispermeabletoallmoleculesof5ooodaltonsorless.Otherproteins in this membraneinclude enzymes involved inmitochondrial lipidsynthe-sisand enzymesthatconvert lipidsubstratesintoformsthataresubsequentlymetabolizedinthematrix.Innermembrane.Theinnermembrane(red)isfoldedintonumerouscristae,greatlyincreasingitstotalsurfacearea.Itcontainsproteinswiththreetypesoffunctions:(1)thosethatcarryoutthe oxidationreactionsoftheelectron-transportchain,(2)theATPsynthasethatmakesATPinthematrix,and(3)transportproteinsthatallowthepassageofmetabolitesintoandoutofthematrix.Anelectrochemicagradient of Ht,which drives theATP synthase,is established across this membrane,sothemembranemustbeimpermeabletoionsandmostsmall chargedmolecules.MatrixMatrix.This large internal space contains a highly concentrated mixture ofhundreds ofenzymes,includingthose requiredfortheoxidationofpyruvate andfattyacidsandforthecitricacidcycle.ThematrixalsocontainsseveralidenticalcopiesofthemitochondrialDNAgenome,special mitochondrialribosomes,tRNAsandvariousenzvmesreauiredforexpressionofthemitochondrialaenes.Intermembrane space.This space (white)contains several enzymes thatusetheATPpassingoutofthematrixtophosphorylateothernucleotides.Figure14-8part3of3.MolecularBiologyoftheCell,4thEdition.·ATP,ADP,P,Mg+,Ca2,K12.Many.solublemetabolicintermediates
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earlyanaerobicprocaryoticcellWhere did we get mitos?DNAFORMATIONOFNUCLEUSMSS.We inherit mitos from ouraerobicanaerobicprocaryoteeucaryoticmothers.cell lackingmitochondria.Our early evolutionary cells areEUCARYOTICCELLENGULFSAEROBICPROCARYOTICCELLBYENDOCYTOSISthought to have incorporatedeucaryoticprokaryotic cells capable of公cell carrying25aerobicperforming cellular respiration--aprocaryoticendosymbiontharmonious symbioticTRANSFEROFGENESFROMPROCARYOTErelationship between earlyTONUCLEUSpresent-dayeukaryote and prokaryote iseucaryoticcellthought to have produced ourpresent-daycells through symbiosismitochondrionnucleusanaerobiceucaryotic cellFigure14-56.MolecularBiologyoftheCell,4thEdition.13
•We inherit mitos from our mothers. •Our early evolutionary cells are thought to have incorporated prokaryotic cells capable of performing cellular respiration-a harmonious symbiotic relationship between early eukaryote and prokaryote is thought to have produced our cells through symbiosis. Where did we get mitos? 13
THEGENETICSYSTEMSOFMITOCHONDRIA-containtheir own genomes,aswell as their own biosynthetic machineryformakingRNAandorganelleproteinsRed:nucleargenomeBrightyellowspots:mitochondrialgenomeGreen:mitochondrialmatrixspace1425μm
THE GENETIC SYSTEMS OF MITOCHONDRIA -contain their own genomes, as well as their own biosynthetic machinery for making RNA and organelle proteins. Red: nuclear genome Bright yellow spots: mitochondrial genome Green: mitochondrial matrix space 14
Electron Transport chainMany of the genes encode the transport chainGenesCategory125TRNACytbNADHAMT-ND1,MT-ND2,MT-ND3,MTPT0/16,569V165dehydrogenaND4,MT-ND4LMT-ND5,MT-ND6ND6rRNAALHONse(15,257)(complex I)OComplexl福Complex IlICoenzymeQMT-CYBLHONComplexIVND1ND5(3,460)-cytochromeATPsynthaseLHONTransferRNAQ(4,160)CRibosomal RNA杭MOControlregionofDNAreductase/CyHND2LHONtochrome b(11,778)(complex II)ND4MERRFcytochromecMT-CO1,MT-CO2,MT-CO3(8,344)RND4LGoxidaseATPasesSDCOIWD3K(complex /V)COIICOII15ATPase6ATPsynthaseMT-ATP6,MT-ATP8
Electron Transport chain Many of the genes encode the transport chain Category Genes NADH dehydrogena se (complex I) MT-ND1, MT-ND2, MT-ND3, MTND4, MT-ND4L, MT-ND5, MT-ND6 Coenzyme Q - cytochrome c reductase/Cy tochrome b (complex III) MT-CYB cytochrome c oxidase (complex IV) MT-CO1, MT-CO2, MT-CO3 ATP synthase MT-ATP6, MT-ATP8 15