Lipids Lipids: Biochemistry, Biotechnology and Health SIXTHEDITION (formerlyLipidBiochemistry:AnIntroduction,Editions1–5) BY Michael I. Gurr John L. Harwood Keith N. Frayn Denis J. Murphy Robert H. Michell Thiseditionfirstpublished20162016byJohnWiley&SonsLtd Firstedition1971MichaelI.GurrandA.T.James;Secondedition1975MichaelI.GurrandA.T.James;Thirdedition1980MichaelI.Gurrand A.T.James;Fourthedition1991MichaelI.GurrandJohnL.Harwood;Fifthedition2002MichaelI.Gurr,JohnL.HarwoodandKeithN.Frayn; Registeredoffice: JohnWiley&Sons,Ltd,TheAtrium,SouthernGate,Chichester,WestSussex,PO198SQ,UK Editorialoffices: 9600GarsingtonRoad,Oxford,OX42DQ,UK TheAtrium,SouthernGate,Chichester,WestSussex,PO198SQ,UK 111RiverStreet,Hoboken,NJ07030-5774,USA Fordetailsofourglobaleditorialoffices,forcustomerservicesandforinformationabouthowtoapplyforpermissiontoreusethecopyrightmaterial inthisbookpleaseseeourwebsiteatwww.wiley.com/wiley-blackwell. 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LimitofLiability/DisclaimerofWarranty:Whilethepublisherandauthor(s)haveusedtheirbesteffortsinpreparingthisbook,theymakeno representationsorwarrantieswithrespecttotheaccuracyorcompletenessofthecontentsofthisbookandspecificallydisclaimanyimplied warrantiesofmerchantabilityorfitnessforaparticularpurpose.Itissoldontheunderstandingthatthepublisherisnotengagedinrendering professionalservicesandneitherthepublishernortheauthorshallbeliablefordamagesarisingherefrom.Ifprofessionaladviceorotherexpert assistanceisrequired,theservicesofacompetentprofessionalshouldbesought. LibraryofCongressCataloging-in-PublicationData Names:Gurr,M.I.(MichaelIan),author.|Harwood,JohnL.,author.|Frayn K.N.(KeithN.),author.|Murphy,DenisJ.,author|Michell,R.H.,author. Lipidbiochemistry.Precededby(work): Title:Lipids:Biochemistry,BiotechnologyandHealth/byMichaelI.Gurr,John L.Harwood,KeithN.Frayn,DenisJ.Murphy,andRobertH.Michell. Description:6thedition.|Chichester,WestSussex;Hoboken,NJ:John Wiley&SonsInc.,2016.|PrecededbyLipidbiochemistry/byMichaelI. Gurr,JohnL.Harwood,andKeithN.Frayn.5thed.2002.|Includes bibliographicalreferencesandindex. Identifiers:LCCN2016000533(print)|LCCN2016002203(ebook)|ISBN 9781118501139(pbk.)|ISBN9781118501085(AdobePDF)|ISBN 9781118501108(ePub) Subjects:|MESH:Lipids Classification:LCCQP751(print)|LCCQP751(ebook)|NLMQU85|DDC 572/.57–dc23 LCrecordavailableathttp://lccn.loc.gov/2016000533 AcataloguerecordforthisbookisavailablefromtheBritishLibrary. Wileyalsopublishesitsbooksinavarietyofelectronicformats.Somecontentthatappearsinprintmaynotbeavailableinelectronicbooks. Coverimages:Leftpanel:Anarterypartiallyoccludedbyanatheroscleroticplaque(Section10.5.1). Theredstainisformacrophagesthatare presentintheplaqueandbecomefoamcells.Thegreenstainisforsmoothmusclecellsinthearterialwallandcappingtheplaque. Photocourtesy ofThomasS.DaviesandSusanChazi,CardiffUniversity,UKfromworkfundedbytheBritishHeartFoundation. Middlepanel:Anenterocytefromhumanjejunumdisplayingmultiplelipiddropletsafewhoursafterconsumingafattymeal(Section7.1.3). Thefigurealsoshowsmitochondria(dark)andthemicrovilli(brushborder). ElectronmicrographcourtesyofDrMDeniseRobertson,University ofSurrey,UKfromworkfundedbytheBiotechnologyandBiologicalSciencesResearchCouncil(BBSRC). Reproduced,withpermissionfrom BMJPublishingGroupLtd,fromMDRobertson,MParkes,BFWarrenetal.(2003)Mobilizationofenterocytefatstoresbyoralglucoseinman. Gut6:833–8. Rightpanel:DistributionofdifferentmolecularspeciesofphosphatidylcholinewithindevelopingoilseedrapeembryosasrevealedbyMALDI-MS imaging(Section9.3.1). Redshowshighconcentrationsandgreenlow. PhotocourtesyofHelenWoodfieldandDrewSturteventfromwork fundedbytheBBSRCinProf.KentChapman’slaboratoryattheUniversityofNorthTexas,USA. Background:Gettyimages/manuelaschewe-behnisch/eyeem Setin8.5/12pt,MeridienLTStd-RomanbyThomsonDigital,Noida,India 1 2016 Contents Preface,xv 2.1.3 Unsaturatedfattyacids,14 Acknowledgements,xvii 2.1.3.1 Monounsaturated(monoenoic) fattyacids,14 Abouttheauthors,xix 2.1.3.2 Polyunsaturated(polyenoic) Aboutthecompanionwebsite,xxi fattyacids,15 2.1.4 Cyclicfattyacids,17 1 Lipids:definitions,naming,methodsandaguideto 2.1.5 Oxyfattyacids,17 thecontentsofthisbook,1 2.1.6 Fattyaldehydesandalcohols,18 1.1 Introduction,1 2.1.7 Somepropertiesoffattyacids,18 1.2 Definitions,1 2.1.8 Quantitativeandqualitativefattyacid 1.3 Structuralchemistryandnomenclature,1 analysis,19 1.3.1 Nomenclature,general,1 2.1.8.1 Generalprinciples,19 1.3.2 Nomenclature,fattyacids,2 2.1.8.2 Determinationofthestructure 1.3.3 Isomerisminunsaturatedfattyacids,2 ofanunknownacid,20 1.3.4 Alternativenames,3 2.2 Storagelipids–triacylglycerolsandwax 1.3.5 Stereochemistry,3 esters,20 1.3.6 Abbreviationofcomplexlipidnames 2.2.1 Introduction,20 andotherbiochemicalterms,3 2.2.2 Thenamingandstructureofthe acylglycerols(glycerides),20 1.4 Lipidomics,4 2.2.2.1 Introduction,20 1.4.1 Introduction,4 2.2.2.2 Allnaturaloilsarecomplex 1.4.2 Extractionoflipidsfromnatural mixturesofmolecular samples,4 species,22 1.4.3 Chromatographicmethodsfor 2.2.2.3 Generalcommentsabout separatinglipids,4 storagetriacylglycerolsin 1.4.4 Modernlipidomicsemploysa animalsandplants,24 combinationofliquidchromatography 2.2.3 Waxesters,25 orgaschromatographywithmass spectrometrytoyielddetailedprofilesof 2.2.4 Surfacelipidsincludenotonlywax naturallipids–the‘lipidome’,6 estersbutawidevarietyoflipid molecules,25 1.5 Aguidetothecontentsofthisbook,8 2.3 Membranelipids,26 Keypoints,11 2.3.1 Generalintroduction,26 Furtherreading,12 2.3.2 Glycerolipids,27 2 Importantbiologicallipidsandtheirstructures,13 2.3.2.1 Phosphoglyceridesarethe 2.1 Structureandpropertiesoffattyacids,13 majorlipidcomponents 2.1.1 Saturatedfattyacids,13 ofmostbiological 2.1.2 Branched-chainfattyacids,13 membranes,27 v Contents vi 2.3.2.2 Phosphonolipidsconstitutea 3.1.7 Thebiosynthesisofhydroxyfattyacids rareclassoflipidsfoundina resultsinhydroxylgroupsindifferent feworganisms,27 positionsalongthefattyacidchain,67 2.3.2.3 Glycosylglyceridesare 3.1.8 Thebiosynthesisofunsaturatedfatty particularlyimportant acidsismainlybyoxidative componentsofphotosynthetic desaturation,68 membranes,29 3.1.8.1 Monounsaturatedfatty 2.3.2.4 Betainelipidsareimportantin acids,68 someorganisms,31 3.1.8.2 Polyunsaturatedfattyacids,70 2.3.2.5 Ether-linkedlipidsandtheir 3.1.8.3 Formationofpolyunsaturated bioactivespecies,31 fattyacidsinanimals,75 2.3.3 Sphingolipids,32 3.1.9 Biohydrogenationofunsaturatedfatty 2.3.4 Sterolsandhopanoids,36 acidstakesplaceinrumen 2.3.4.1 Majorsterols,36 microorganisms,75 2.3.4.2 Othersterolsandsteroids,39 3.1.10Thebiosynthesisofcyclicfattyacids providedoneofthefirstexamplesofa 2.3.4.3 Hopanoidsandrelated complexlipidsubstrateforfattyacid lipids,39 modifications,77 2.3.5 Membranelipidsofthearchaea,40 3.1.11Controloffattyacidbiosynthesisin Keypoints,42 differentorganisms,78 Furtherreading,42 3.1.11.1Substratesupplyfordenovo 3 Fattyacidmetabolism,44 fattyacidbiosynthesis,78 3.1 Thebiosynthesisoffattyacids,44 3.1.11.2Acetyl-CoAcarboxylaseandits regulationinanimals,79 3.1.1 Conversionoffattyacidsinto metabolicallyactivethioestersisoftena 3.1.11.3Acetyl-CoAcarboxylase prerequisitefortheirmetabolism,44 regulationinother organisms,81 3.1.1.1 Acyl-CoAthioesterswerethe firsttypesofactivatedfatty 3.1.11.4Regulationoffattyacid acidstobediscovered,45 synthase,82 3.1.1.2 Acyl-acylcarrierproteinscan 3.1.11.5Controlofanimal befoundasdistinctmetabolic desaturases,84 intermediatesinsome 3.2 Degradationoffattyacids,85 organisms,47 3.2.1 β-Oxidationisthemostcommontypeof 3.1.2 Thebiosynthesisoffattyacidscanbe biologicaloxidationoffattyacids,85 dividedintodenovosynthesisand 3.2.1.1 Cellularsiteofβ-oxidation,85 modificationreactions,47 3.2.1.2 Transportofacylgroupstothe 3.1.3 Denovobiosynthesis,48 siteofoxidation:theroleof 3.1.3.1 Acetyl-CoAcarboxylase,49 carnitine,85 3.1.3.2 Fattyacidsynthase,50 3.2.1.3 Controlofacyl-carnitineisvery 3.1.3.3 Chaintermination,62 important,87 3.1.4 Mitochondrialfattyacid 3.2.1.4 Enzymesofmitochondrial synthase,63 β-oxidation,87 3.1.5 Elongation,63 3.2.1.5 Otherfattyacidscontaining 3.1.6 Branched-chainfattyacids,65 branched-chains,doublebonds Contents vii andanoddnumberofcarbon 3.5.13Importantnewmetabolitesofthen-3 atomscanalsobeoxidized,88 PUFAs,eicosapentaenoicand 3.2.1.6 Regulationofmitochondrial docoasahexaenoicacidshaverecently β-oxidation,89 beendiscovered,115 3.2.1.7 Fattyacidoxidationin 3.5.14Foreicosanoidbiosynthesis,an E.coli,91 unesterifiedfattyacidisneeded,118 3.2.1.8 β-Oxidationinmicrobodies,91 3.5.15Essentialfattyacidactivityisrelatedto 3.2.2 α-Oxidationoffattyacidsisimportant doublebondstructureandtotheability ofsuchacidstobeconvertedinto whensubstratestructureprevents β-oxidation,93 physiologicallyactiveeicosanoids,119 3.2.3 ω-Oxidationusesmixed-function Keypoints,120 oxidases,94 Furtherreading,121 3.3 Chemicalperoxidationisanimportant 4 Themetabolismofcomplexlipids,124 reactionparticularlyofpolyunsaturatedfatty 4.1 Thebiosynthesisoftriacylglycerols,124 acids,95 4.1.1 Theglycerol3-phosphatepathwayin 3.4 Peroxidationcatalysedbylipoxygenase mammaliantissuesprovidesalink enzymes,96 betweentriacylglyceroland 3.4.1 Lipoxygenasesareimportantfor phosphoglyceridemetabolism,124 stressresponsesanddevelopment 4.1.2 Thedihydroxyacetonephosphate inplants,97 pathwayinmammaliantissuesisa 3.5 Essentialfattyacidsandthebiosynthesisof variationtothemainglycerol eicosanoids,100 3-phosphatepathwayandprovidesan 3.5.1 Thepathwaysforprostaglandin importantroutetoetherlipids,127 biosynthesisarediscovered,101 4.1.3 Formationoftriacylglycerolsinplants 3.5.2 Prostaglandinbiosynthesisby involvesthecooperationofdifferent cyclo-oxygenases,101 subcellularcompartments,128 3.5.3 Nonsteroidalanti-inflammatorydrugs 4.1.4 Somebacteriamakesignificantamounts arecyclo-oxygenaseinhibitors,103 oftriacylglycerols,132 3.5.4 Cyclicendoperoxidescanbe 4.1.5 Themonoacylglycerolpathway,132 convertedintodifferenttypesof 4.2 Thecatabolismofacylglycerols,133 eicosanoids,104 4.2.1 Thenatureanddistributionof 3.5.5 Neweicosanoidsarediscovered,105 lipases,133 3.5.6 Thecyclo-oxygenaseproductsexerta 4.2.2 Animaltriacylglycerollipasesplayakey rangeofactivities,106 roleinthedigestionoffoodandinthe 3.5.7 Prostanoidshavereceptorsthatmediate uptakeandreleaseoffattyacidsby theiractions,107 tissues,134 3.5.8 Prostaglandinsandothereicosanoids 4.2.3 Plantlipasesbreakdownthelipids arerapidlycatabolized,108 storedinseedsinaspecialized 3.5.9 Insteadofcyclo-oxygenation, organelle,theglyoxysome,135 arachidonatecanbelipoxygenatedor 4.3 Theintegrationandcontrolofanimal epoxygenated,108 acylglycerolmetabolism,136 3.5.10Controlofleukotrieneformation,108 4.3.1 Fueleconomy:theinterconversionof 3.5.11Physiologicalactionofleukotrienes,110 differenttypesoffuelsishormonally 3.5.12CytochromeP450oxygenations,112 regulatedtomaintainnormalblood Contents viii glucoseconcentrationsandensure 4.5.9 Differencesbetweenphosphoglyceride storageofexcessdietaryenergyin biosynthesisindifferentorganisms,154 triacylglycerols,136 4.5.10Plasmalogenbiosynthesis,154 4.3.2 Thecontrolofacylglycerolbiosynthesis 4.5.11Plateletactivatingfactor:abiologically isimportant,notonlyforfueleconomy activephosphoglyceride,156 butformembraneformation,requiring 4.6 Degradationofphospholipids,157 closeintegrationofstorageand 4.6.1 Generalfeaturesofphospholipase structurallipidmetabolism,137 reactions,157 4.3.3 Mobilizationoffattyacidsfromthefat 4.6.2 PhospholipaseAactivityisusedto storesisregulatedbyhormonalbalance, removeasinglefattyacidfromintact whichinturnisresponsiveto phosphoglycerides,158 nutritionalandphysiologicalstates,140 4.6.3 PhospholipaseBand 4.3.4 Regulationoftriacylglycerol lysophospholipases,161 biosynthesisinoilseeds,143 4.6.4 PhospholipasesCandDremovewater- 4.4 Waxesters,143 solublemoieties,161 4.4.1 Occurrenceandcharacteristics,143 4.6.5 Phospholipidsmayalsobecatabolized 4.4.2 Biosynthesisofwaxestersinvolvesthe bynonspecificenzymes,162 condensationofalong-chainfatty 4.6.6 Endocannabinoidmetabolism,162 alcoholwithfattyacyl-CoA,145 4.7 Metabolismofglycosylglycerides,163 4.4.3 Digestionandutilizationofwaxestersis poorlyunderstood,145 4.7.1 Biosynthesisofgalactosylglycerides takesplaceinchloroplast 4.4.4 Surfacelipidsincludewaxestersanda envelopes,163 widevarietyofotherlipids,146 4.7.2 Catabolismofgalactosylglycerides,164 4.5 Phosphoglyceridebiosynthesis,146 4.7.3 Metabolismoftheplant 4.5.1 Tracerstudiesrevolutionizedconcepts sulpholipid,164 aboutphospholipids,146 4.8 Metabolismofsphingolipids,165 4.5.2 Formationoftheparentcompound, phosphatidate,isdemonstrated,147 4.8.1 Biosynthesisofthesphingosinebase andceramide,165 4.5.3 Anovelcofactorforphospholipid biosynthesiswasfoundby 4.8.2 Cerebrosidebiosynthesis,166 accident,147 4.8.3 Formationofcomplex 4.5.4 Thecorereactionsofglycerolipid glycosphingolipids,167 biosynthesisarethoseoftheKennedy 4.8.4 Gangliosidebiosynthesis,167 pathway,147 4.8.5 Sulphatedsphingolipids,169 4.5.5 Thezwitterionicphosphoglycerides 4.8.6 Sphingomyelinisbothasphingolipid canbemadeusingcytidine andaphospholipid,170 diphospho-bases,149 4.8.7 Catabolismofthesphingolipids,170 4.5.6 CDP-diacylglycerolisanimportant 4.8.8 Sphingolipidmetabolisminplantsand intermediateforphosphoglyceride yeast,172 formationinallorganisms,150 4.9 Cholesterolbiosynthesis,173 4.5.7 Phosphatidylserineformationin 4.9.1 Acetyl-CoAisthestartingmaterialfor mammals,152 polyisoprenoid(terpenoid)aswellas 4.5.8 AllphospholipidformationinE.coliis fattyacidbiosynthesis,174 viaCDP-diacylglycerol,152