lipid chemistry power point and some .pptx

lipid metabolism

1. Lipid chemistry 1 Yenas Wulugeta /biechem/A2

2. Lipids Chemically diverse group of compounds low solubility in water high solubility in nonpolar solvents Play diverse biological function energy storage structural component emulsifying agents - Some lipids, like bile salts , act as emulsifying agents . They help break down fat globules into smaller droplets, allowing for better digestion and absorption of dietary fats in the intestines. This is especially important in the digestive process. H ormones - steroid hormones and ecosianides intracellular messengers represent highly reduced forms of carbon largely hydrocarbon in nature metabolic energy storage Lipids Hydrophobic Totally insoluble in water Amphiapathic Sparingly soluble in water 2

3. Classificatien ef lipids Simple lipids Esters of fatty acids with various alcohols FA + Glycerol FA + HMW alcohol Fats Wax 2. Complex lipids 3 Containing groups in addition to an alcohol and a fatty acid Phospholipids Containing phosphoric acid residue Glycolipids Containig sphingosine and carbohydrate Lipoproteins Conjugated with protein Derived lipids precursors or derived products of lipids Fatty acids Glycerol Ketone bodies -used by brain, skeletal muscle, heart and kidney.

4. Fatty acids carboxylic acids with hydrocarbon chains Differ in Chain length SCFA MCFA LCFA Level of unsaturation Saturated FA all carbon–carbon bonds are single bonds Unsaturated FA one or more double bonds (cis) in the HC chain Monounsaturated FA Polyunsaturated FA Structure Linear -energy storage, cell membrane signaling like ecocyanides Branched - in membrane structure Cyclic - prostaglandin,/ arachidonic acids derivative, used in inflammation regulation, immiune response, and blood clotting 4

5. Physical property of FA determined by Chain length Degree of unsaturation Longer chain fewer double bonds reduced solubility high melting point 5

6. femenclature ef FAs Systematic Based on Carbon number Level of unsaturation Common name Based on the source from which the FA was first spotted Shorthand notation Provides SH N o of carbon atoms N o of unsaturation Sites of unsaturation STR SYS COM Mpt 6

7. Essential fatty acids not synthesized by mammals necessary for normal growth and life must be obtained from diet linoleic acid Linolenic acids Arachidonic acid Synthesized from linoleic acid Serve as precursor for the synthesis of eicosanoids Linoleic acid Linolenic acid Arachidonic acid 7

8. Acylglycerels Glycerol with one or more fatty acids attached through ester linkages MAG DAG TAG Triacylglycerol Major energy reserve Rich in highly reduced carbon Provides insulation Simple Same FAs Mixed Different FAs Unsaturated FAs usually found at C- 2 8

9. hespheacylglycerels 1,2- diacylglycerol that has a phosphate group at C- 3 Phosphatidic acid are amphiapathic are components of membrane Phosphatidic acid parent compound for glycerophospholipids polar groups are esterified to the phosphoric acid moiety Phosphate + esterified entity head group 9

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11. hesphelipases enzymes that cause the breakdown of phospholipids Phospholipase A1: removes FA on C1 Phospholipase A2: removes FA on C2 (arachidonic acid) Phospholipase C : cleaves phosphate- glycerol bond. Phospholipase D : cleaves phosphate- head group bond. 11

12. Ether glycerophosph olipids Posses an ether linkage at C- 1 12 Platelet activating factor (PAF) C- 2 contains acetate More water soluble Plasmalogens - have im portance in fluidity C- 1 contains cis - α , β -unsaturated FA Head groups choline ethanolamine Serine

13. Sphingelipids 13 Contain sphingosine as a backbone Attach fatty acids by amide bond Ceramide Membrane component Constituents of lipoproteins Function Structure ✓ Signal transduction Sphingomyelin Phosphosphingolipid ( phosphodiester bond) Used in nerve myelination Formed by esterification of ceramide with Phosphorylcholine Phosphorylethanolamine

14. Glycesphingelipids 14 Ceramide with one or more sugar residues Neutral glycospingolipids Contain uncharged sugar residue Cerbosides Contain single molecule of Glc Gal Acidic glycosphingolipid Ganglosides Ceramide esterified with three or more sugar containing Sialic acid ➢

15. sulfatides Contain sulfate esterified with Gal Involved in Neuronal cell differentiation Myelin formation 15

16. Isoprenoids Contain repetitive five carbon structural units Isoprenes Types 1) Terpenes 16

17. 2) Steroids is of Are derivatives of triterpenes Composed of four fused rings Cholesterol Is amphiapathic Component of cell membrane Precursor for the synthes Steroid hormones like sex hormone and coricosteroids Vitamin D Bile salts 17

18. Lipepreteins Molecular complexes used for lipid transport in circulation Structure Spherical Neutral lipid core TG,CE Surface monolayer amphiapathic lipids and proteins PL, Cholesterol, Apo proteins 18

19. Classificatien ef lipepreteins Classified based on density total lipid content is inversely correlated with the density of the lipoproteins Lipid/protein Lipid/protein Low density High density 19

20. Functien ef lipepreteins Chylomicron Largest and lipid rich Transport lipid from intestine to adipose and muscle Have apo protein B- 48, C- II VLDL Synthesized in the liver Transport lipid to tissues Contain apo proteins B- 100, C- II, E LDL Have high concentration of cholesterol and CE Provide cholesterol to peripheral tissue Have apo protein B- 100 HDL Secreted from liver and intestine Reverse cholesterol transport Have apo proteins C- II,E,A 20

21. Bielegical membranes Are external boundaries of cells regulate the molecular traffic across that boundary forms discrete compartments in the cell Help in cell to cell recognition They are flexible Shape changes They are selectively permiable Impermeable for polar molecules Permeable to non- polar molecules Composed of Proteins Polar lipids Glycoproteins and glycolipids Proportion will differ based on the type of membrane 21

22. Fluid mesaic medel ef membranes Is a bilayer of phospholipid where Non polar regions Polar head groups face the core face outward Proteins are embedded in the bilayer Hydrophobic interaction Individual lipid and protein units are free to change Non covalent interaction 22