DynamicEnergyBudgettheory動(dòng)態(tài)能量預(yù)算理論

會(huì)計(jì)學(xué)1DynamicEnergyBudgettheory動(dòng)態(tài)能量預(yù)算理論EmpiricalspecialcasesofDEB11.1yearauthormodelyearauthormodel1780Lavoisiermultipleregressionofheatagainstmineralfluxes1950Emersoncuberootgrowthofbacterialcolonies1825GompertzSurvivalprobabilityforaging1951Huggett&Widdasfoetalgrowth1889Arrheniustemperaturedependenceofphysiologicalrates1951Weibullsurvivalprobabilityforaging1891Huxleyallometricgrowthofbodyparts1955Bestdiffusionlimitationofuptake1902HenriMichaelis--Mentenkinetics1957Smithembryonicrespiration1905Blackmanbilinearfunctionalresponse1959Leudeking&Piretmicrobialproductformation1910HillCooperativebinding1959Hollinghyperbolicfunctionalresponse1920PüttervonBertalanffygrowthofindividuals1962Marr&Pirtmaintenanceinyieldsofbiomass1927Pearllogisticpopulationgrowth1973Droopreserve(cellquota)dynamics1928Fisher&TippittWeibullaging1974Rahn&Arwaterlossinbirdeggs1932Kleiberrespirationscaleswithbodyweight3/41975Hungatedigestion1932Mayneordcuberootgrowthoftumours1977Beer&AndersondevelopmentofsalmonidembryosDEBtheoryisaxiomatic,basedonmechanismsnotmeanttoglueempiricalmodelsSincemanyempiricalmodelsturnouttobespecialcasesofDEBtheorythedatabehindthesemodelssupportDEBtheoryThismakesDEBtheoryverywelltestedagainstdata第1頁/共23頁Empiricalpatterns:stylisedfactsFeeding

Duringstarvation,organismsareabletoreproduce,growandsurviveforsometimeAtabundantfood,thefeedingrateisatsomemaximum,independentoffooddensityGrowth

ManyspeciescontinuetogrowafterreproductionhasstartedGrowthofisomorphicorganismsatabundantfoodiswelldescribedbythevonBertalanffyFordifferentconstantfoodlevelstheinversevonBertalanffygrowthrateincreaseslinearlywithultimatelengthThevonBertalanffygrowthrateofdifferentspeciesdecreasesalmostlinearlywiththemaximumbodylengthFetusesincreaseinweightapproximatelyproportionaltocubedtimeReproduction

Reproductionincreaseswithsizeintra-specifically,butdecreaseswithsizeinter-specificallyRespiration

AnimaleggsandplantseedsinitiallyhardlyuseO2TheuseofO2increaseswithdecreasingmassinembryosandincreaseswithmassinjuvenilesandadultsTheuseofO2scalesapproximatelywithbodyweightraisedtoapowercloseto0.75Animalsshowatransientincreaseinmetabolicrateafteringestingfood(heatincrementoffeeding)Stoichiometry

Thechemicalcompositionoforganismsdependsonthenutritionalstatus(starvedvswell-fed)ThechemicalcompositionoforganismsgrowingatconstantfooddensitybecomesconstantEnergy

Dissipatingheatisaweightedsumof3massflows:CO2,O2andN-wasteFromSousaetal2008Phil.Trans.R.Soc.Lond.B

363:2453-2464第2頁/共23頁Empiricalpatterns111.1aFromSousaetal2008Phil.Trans.R.Soc.Lond.B

363:2453-2464第3頁/共23頁Empiricalpatterns211.1bFromSousaetal2008Phil.Trans.R.Soc.Lond.B

363:2453-2464第4頁/共23頁Topologicalalternatives11.1cFromLika&Kooijman2011J.SeaRes66:381-391第5頁/共23頁Testofproperties11.1dFromLika&Kooijman2011J.SeaRes,66:381-391第6頁/共23頁ApplicationsofDEBtheory11.1ebioproduction:agronomy,aquaculture,fisheriespestcontrolbiotechnology,sewagetreatment,biodegradation(eco)toxicology,pharmacologymedicine:cancerbiology,obesity,nutritionbiologyglobalchange:biogeochemicalclimatemodelingconservationbiology;biodiversityeconomy;sustainabledevelopmentFundamentalknowledgeofmetabolicorganisationhasmanypracticalapplications第7頁/共23頁InnovationsbyDEBtheory11.1fUnifiesalllifeonearth(bacteria,protoctists,fungi/animals,plants)LinkslevelsoforganisationExplainsbodysizescalingrelationshipsDealswithenergeticandstoichiometricconstraintsIndividualsthatfollowDEBrulescanmergesmoothly intoasymbiosisthatagainfollowsDEBrulesMethodfordeterminingentropyoflivingbiomassBiomasscompositiondependsongrowthrateProductformationhas3degreesoffreedomExplainsindirectcalorimetryExplainshowyieldofbiomassdependsongrowthrateQuantitativepredictionshavemanypracticalapplications第8頁/共23頁DEBtheoryrevealsunexpectedlinks11.1gLength,mmO2consumption,μl/h1/yield,mmolglucose/mgcells1/specgrowthrate,1/hDaphniaStreptococcusrespirationlengthinindividualanimals&yieldgrowthinpopofprokaryotes

havealotincommon,asrevealedbyDEBtheoryReserveplaysanimportantroleinbothrelationships,butyouneedDEBtheorytoseewhyandhow第9頁/共23頁Weirdworldatsmallscale11.2aAlmostalltransformationsincellsareenzymemediatedClassicenzymekinetics:basedonchemicalkinetics(industrialenzymes)

diffusion/convectionlawofmassaction:transformationrateproductofconc.ofsubstrateslargernumberofmoleculesconstantreactorvolumeProblematicapplicationincellularmetabolism:

definitionofconcentration(compartments,movingorganelles)transportmechanisms(proteinswithaddresslabels,targetting,allocation)crowding(presenceofmanymacro-moleculesthatdonotpartakeintransformation)intrinsicstochasticityduetosmallnumbersofmoleculesliquidcrystallinepropertiessurfacearea-volumerelationships:membrane-cytoplasm;polymer-liquidconnectivity(manymetabolitesareenergysubstrate&buildingblock;dilutionbygrowth)Alternativeapproach:reconstructionoftransformationkineticsonthebasisofcellularinput/outputkinetics第10頁/共23頁Diffusioncannotoccurincells11.2b第11頁/共23頁Self-ionizationofwaterincells11.2cAcellofvolume0.25mm3andpH7at25°Chasm=14protonsN=8109watermoleculesconfidenceintervalsofpH95,90,80,60%pHcellvolume,m3modifiedBesselfunction7第12頁/共23頁Crowdingaffectstransport11.2dcytoskeletalpolymersribosomesnucleicacidsproteins第13頁/共23頁ATPgeneration&use11.2e5106ATPmoleculesinbacterialcellenoughfor2sofbiosyntheticworkOnlyusedifenergygenerating&energydemandingtransformationsareatdifferentsite/timeIfADP/ATPratiovaries,thenratesofgeneration&usevaries,butnotnecessarilytheratesoftransformationstheydriveProcessesthatarenotmuchfasterthancellcycle,shouldbelinkedtolargeslowpoolsofmetabolites,nottosmallfastpoolsDEBtheoryusesreserveaslargeslowpoolfordrivingmetabolism第14頁/共23頁Classicenergetics

11.3Anabolism:syntheticpathwaysCatabolism:degradationpathwaysDuality:compoundsassourceforenergyandbuildingblocksInDEB:fromfoodtoreserve;fromreservetostructureFrom:Mader,S.S.1993Biology,WCBThisdecompositionoccursatseveralplacesinDEBs第15頁/共23頁Classicenergetics

11.3aFrom:Duve,C.de1984Aguidedtourofthelivingcell,Sci.Am.Lib.,NewYorkheterotrophautotrophTheclassicconceptonmetabolicregulationfocussesonATPgenerationanduse.TheapplicationofthisconceptinDEBtheoryisproblematic.第16頁/共23頁StaticEnergyBudgets11.3bFrom:Brafield,A.E.andLlewellyn,M.J.1982Animalenergetics,Blackie,GlasgowCenergyfromfoodPproduction(growth)FenergyinfaecesUenergyinurineRheatNumbers:kJin28dBasicdifferencewithdynamicbudgets:Productionisquantifiedasenergyfixedinnewtissue,notasenergyallocatedtogrowth:excludesoverheadsHeatincludesoverheadsofgrowth,reproductionandotherprocesses,itdoesnotquantifymaintenancecosts第17頁/共23頁StaticvsDynamicBudgets11.4

Netproductionmodelstime-dependentstaticmodelsnodempingbyreserveAssimilationmodelsdynamicsbynaturereservedampsfoodfluctuations第18頁/共23頁StaticEnergyBudgets(SEBs)11.4aDifferenceswithDEBsoverheadsinterpretationofrespirationinterpretationofurinationmetabolicmemorylifecycleperspectivechangeinstatesgrossingestedfaecesurineapparentassimilatedgrossmetabolisednetmetabolisedspecdynamicactionworkmaintenancesomaticmaintenanceactivitythermoregulationproductiongrowthproductsreproduction第19頁/共23頁P(yáng)roductionmodel11.4cfoodfaecesassimilationfeedingdefecationmaintenanceoffspringreproductionreservestructuregrowth第20頁/共23頁P(yáng)roductionmodels11.4dnoaccommodationforembryonicstage;requireadditionalstatevariables(nofoodintake,stillmaintenancecostsandgrowt