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1、liguofu11 Lipids 11.1 Storage lipids 11.2 Structural lipids in membranes 11.3 Lipids as signals, cofactors, and pigments 11.4 Separation and analysis of lipidsliguofuStorage lipidsTriacylglycerolsWaxesfatty acids (C14-36)Alcohols (C16-30)+High melting points (60-100 C)Energy storage (Plankton, 浮游生物浮
2、游生物)Water repellant (birds and plants)liguofuFat cell of pigFat dropletsPlant seed cellStored oil bodiesliguofuTriacontanoylpalmitate (major component of beeswax)(三十烷醇三十烷醇 / 蜂花醇蜂花醇)liguofu月桂酸月桂酸肉豆蔻酸肉豆蔻酸棕櫚酸棕櫚酸硬脂酸硬脂酸花生酸花生酸木蠟酸木蠟酸棕櫚油酸棕櫚油酸油酸油酸亞油酸亞油酸亞麻酸亞麻酸花生四稀酸花生四稀酸liguofuPhysical and chemical propertiesc
3、is double bond causes a kink amphipathic( (兩親性兩親性) )liguofuFA in food (x%)Source Lauric/Myristic Palmitic Stearic Oleic Linoleic Beef 5 26-32 20-25 37-43 2-3 Milk25 12 33 3Coconut 74 10 2 7Corn 8-12 3-4 19-24 34-62Olive 9 2 84 4Palm39 4 40 8Soybean 9 6 20 52Sunflower 6 1 21 66liguofu11 Lipids 11.1 S
4、torage lipids 11.2 Structural lipids in membranes 11.3 Lipids as signals, cofactors, and pigments 11.4 Separation and analysis of lipidsliguofuStructural lipids in membranesGlycerophospholipidsSphingophospholipidsSphingoglycolipidsGlyceroglycolipidsliguofuliguofu1. Glycerophospholipids liguofu磷脂酰乙醇胺
5、磷脂酰乙醇胺, PE磷脂酰膽堿磷脂酰膽堿, PC, 又稱卵磷脂又稱卵磷脂磷脂酰絲氨酸，磷脂酰絲氨酸，PS磷脂酰甘油，磷脂酰甘油， PG 磷脂酰肌醇（磷脂酰肌醇（PI）心磷脂心磷脂雙磷脂酰甘油雙磷脂酰甘油liguofuSome Glycerophospholipids have ether-linked fatty acidsfound in central nervous system and in heart muscle. Its resistant to phospholipases. ( why? )active at very low concentration (0.1nM) re
6、leased from basophils（嗜堿白細胞）（嗜堿白細胞）縮醛磷脂縮醛磷脂血小板激活因子血小板激活因子liguofu ( (神經神經) )鞘氨醇鞘氨醇liguofu神經酰胺神經酰胺( (神經神經) )鞘磷脂鞘磷脂(SM)(SM)腦苷脂腦苷脂神經節(jié)苷脂神經節(jié)苷脂liguofuliguofu ABO blood groupsWhich lipid?liguofu(神經酰胺神經酰胺)liguofuliguofuSphingolipid storage diseasesPathways for the breakdown of GM1, globoside, and sphingomyel
7、in to ceramide. A defect in the enzyme hydrolyzing a particular step is indicated by , and the disease that results from accumulation of the partial breakdown product is noted.Electron micrograph of a portion of a brain cell from an infant with Tay-Sachs disease,liguofuglycerolfatty acid tailGal fat
8、ty acid tailGalsphingosineliguofuGalactolipids and Sulfolipids in Chloroplastsliguofu4. CholesterolSteroids:(i) cholesterol and sterols of plants and fungi(ii) steroid hormones(iii) bile saltsRoles of cholesterol in mammals(i) structural component of plasma membrane and modulates membrane fluidity (
9、ii) precursor of steroid hormones and bile acids Rarely found in plants, never in bacteriaSteroids and lipid vitamines can be classified as polyprenyl compoundsliguofuliguofuArchaebacteria Contain Unique Membrane LipidsThey live in extreme conditionshigh temperatures (boiling water), low pH, high io
10、nic strength. They have membrane lipids containing long-chain (32 carbons) branched hydrocarbons linked at each end to glycerol. These linkages are through ether bonds, which are much more stable to hydrolysis at low pH and high temperature than are the ester bonds found in the lipids of eubacteria
11、and eukaryotes.A typical membrane lipid of archaebacterialiguofu11 Lipids 11.1 Storage lipids 11.2 Structural lipids in membranes 11.3 Lipids as signals, cofactors, and pigments 11.4 Separation and analysis of lipidsliguofu1. Phosphatidylinositols act as intracellular signals2. Eicosanoids (廿烷類廿烷類)
12、carry messages to nearby cells3. Steroid hormones carry messages between tissues4. Vitamins A and D are hormone precursorsliguofu1. Phosphatidylinositols act as intracellular signalsliguofuProstaglandins: PG E (ether-soluble); PGF (phosphate buffer soluble)Thromboxanes: produced by platelets (thromb
13、ocytes) and act in the formation of blood clots.Leukotrienes: Overproduction of leukotrienes cause asthmatic attacks2. Eicosanoids (廿烷類廿烷類) carry messages to nearby cellsparacrine (旁分泌旁分泌) hormones(前列腺素類前列腺素類)(凝血噁烷類凝血噁烷類)(白細胞三烯類白細胞三烯類)liguofu( (花生四烯酸花生四烯酸) )前列腺素類前列腺素類白細胞三烯類白細胞三烯類凝血噁烷凝血噁烷 類類liguofu環(huán)加
14、氧酶環(huán)加氧酶liguofuAspirin and Ibuprofen belong to Non-Steroidal Anti-Inflammatory Drugs ,NSAIDs .Ibuprofen (布洛芬布洛芬) inhibits the same step, probably by mimicking the structure of the substrate or an intermediate in the reaction.Aspirin inhibits the cyclooxgenase activity of COX by acetylating an essentia
15、l Ser residue on the enzyme.liguofuDerivates of sterols;Play important roles in gene expression;Sex hormones and hormones from adrenal cortex;Prednisolone and prednisone are steroid drug with potent antiinflammatory activities.3. Steroid hormones carry messages between tissues 睪丸酮睪丸酮雌二醇雌二醇皮質皮質( (甾甾)
16、 )醇醇, ,氫化可的松氫化可的松醛固酮醛固酮脫氫皮質脫氫皮質( (甾甾) )醇醇強的松強的松liguofu4. Fat soluble Vitaminsvitamins A,D,E,KLong chain polyunsaturates hydrocarbons attached to 1 or 2 benzene ringsVitamin A (retinol) stored in liver precursor:carotene deficiency: night blindnessVitamin D formed from precursor in skin by UV regulat
17、es Ca deposition deficiency: ricketsliguofuliguofuliguofu3Vit D3 is formed in skin1,25-dihydroxy VitD3 is biological active; It regulates gene expression, e.g. turning on the synthesis of an intestinal Ca 2+ binding protein.liguofuVitamins E and K and Lipid Quinones are oxidation-reduction cofactors
18、Vit E: biological antioxidants;Vit K: undergoes a cycle of oxidation and reduction;during the formation of active prothrombin;Warfarin: synthetic compound that inhibits the formation of active prothrombin;Ubiquinone (coenzyme Q) and plastoquitone: isoprenoids that functionas lipophilic electron carr
19、iers in the oxidation-reduction reactionsthat drive ATP synthesis in mitochondria and chloroplasts, respectively. liguofuActive sugar precursorsliguofu11 Lipids 11.1 Storage lipids 11.2 Structural lipids in membranes 11.3 Lipids as signals, cofactors, and pigments 11.4 Separation and analysis of lip
20、idsliguofuSeparation and Analysis of Lipids Lipid extraction requires organic solventsAdsorption chromatography separates lipid of different polarityGas-lipid chromatography resolves mixture of volatile lipid derivatesMass spectrometrySpecific hydrolysisliguofuRoles of Lipids Energy storage (fatty a
21、cids, triacylglycerols) Structural elements (phospholipids, cholesterol) Hormones ( sex hormones e.g. Estrogen) Enzyme cofactors (coenzyme A) Electron carriers (coenzyme Q, plastpquinone) Light-absorbing pigments (carotenoids) Hydrophobic anchors (dolichols) Emulsifying agents (bile salts) Intracellular messengers (phosphatidyl inositol)liguofuThe End
生物化學課件：11 Lipids
