BNUR 2003 Biomedical Chemistry & Lab Diagnostics Lecture Notes PDF

2023-09-19 Amino Acids Peptide Bonds BNUR 2003 Structure Biomedical Chemistry and Lab Diagnostics Classes Denaturation 2-Important Biochemical Molecules and Macromolecules 2-1 Proteins 2-2 Carbohydrates + Lipids 2-3 Nucleic acids and mutations Electrophoresis Enzymes Monosaccharides Disacchar...

2023-09-19 Amino Acids Peptide Bonds BNUR 2003 Structure Biomedical Chemistry and Lab Diagnostics Classes Denaturation 2-Important Biochemical Molecules and Macromolecules 2-1 Proteins 2-2 Carbohydrates + Lipids 2-3 Nucleic acids and mutations Electrophoresis Enzymes Monosaccharides Disaccharides Polysaccharides 1 2 Carbohydrates • Carbohydrates (CHO) make up only 1-2 % of our body weight but provide most our chemical energy! • They are water soluble and are composed of _________, _________ and _________ in a ratio of 1:2:1. • CHO can be simple sugars (monosaccharides and disaccharides) or more complex molecules called polysaccharides. 3 Carbohydrates Five- (pentose) and six-carbon (hexose) sugars are the most common. D-glucose is also called dextrose (blood sugar). Carbonyl Group Hydroxyl group 4 1 2023-09-19 Carbohydrates Carbohydrates The most common form of glucose in our bodies is cyclical in structure. Monosaccharides can be linked to form larger structures. Two monosaccharides are joined by a ____________ link to form a disaccharide. This reaction is another example of dehydration synthesis. Dehydration synthesis Hydrolysis Glucose C6H12O6 Fructose C6H12O6 Glycosidic link Sucrose C12H22O11 Water Disaccharides can be broken down into monosaccharides through hydrolysis. 5 6 Carbohydrates Carbohydrates Polysaccharides consist of tens or hundreds of monosaccharides joined together through dehydration synthesis reactions involving either: • 1,4 glycosidic links or • 1,6 glycosidic links Amylopectin and glycogen are polysaccharides with both 1,4 and 1,6 linkages. Amylopectin & Glycogen: Branched chains = 1,4 and 1,6 linkages Amylose and cellulose both have 1,4 glycosidic links. 7 8 2 2023-09-19 Lipids Unlike carbohydrates, lipids do not share a common base. Instead lipids are substances that can be extracted from tissues using organic solvents. Lipids are insoluble in water. Lipids include: Monosaccharides • • • • Disaccharides Polysaccharides Triglycerides ___________ Phospholipids Steroids Fat-soluble vitamins Phospholipids Other lipids 9 Lipids 10 Lipids Glycerol Triglycerides are the most common lipid. They contribute to body form and serve as an energy reserve. Triglycerides are composed of: • A glycerol backbone • Three fatty acids There are many different types of fatty acids, and the specific fatty acids that form a triglyceride determine its structure and function. 11 Carboxyl group Fatty acid (palmitic acid, Saturated) C15H31COOH Hydrocarbon chain 12 3 2023-09-19 Lipids Lipids Ester linkage Glycerol Oleic acid (unsaturated) (C17H33COOH) Palmitic acid (saturated) (C15H31COOH) + H2O + H2O Stearic acid (saturated) (C17H35COOH) + Fatty acids are: • Usually composed of an even number of carbon atoms (16 and 18 are most common) • Mostly saturated (only single C-C bonds) Characteristics of fatty acids: • Longer carbon chains = higher melting points • All else being equal, higher degree of unsaturation = lower melting points H2O cis configuration Molecule of fat (triglyceride) 13 14 Lipids Fatty acid melting point comparison Lipids Phospholipids consist of a glycerol backbone (like triglycerides) in carbons are linked to fatty acids and the third carbon is a phosphate group. Fatty Acid Structural Formula Isomer M.P. which two Common Name (ºC) ___________________________________________________________________________________ bonded to Butyric CH3(CH2)2-COOH -7.9 Caproic CH3(CH2)4-COOH -3.4 Caprylic CH3(CH2)6-COOH 16.7 Capric CH3(CH2)8-COOH 31.6 Lauric CH3(CH2)10-COOH 44.2 Myristic CH3(CH2)12-COOH 53.9 Palmitic CH3(CH2)14-COOH 63.1 Stearic CH3(CH2)16-COOH 69.6 cis Palmitoleic CH3(CH2)5-CH=CH-(CH2)7-COOH 0 cis Oleic CH3(CH2)7-CH=CH-(CH2)7-COOH 15 trans Elaidic CH3(CH2)7-CH=CH-(CH2)7-COOH 46.5 Linoleic CH3(CH2)4(CH=CH-CH2)2(CH2)6-COOH all cis -5 Linolelaidic CH3(CH2)4(CH=CH-CH2)2(CH2)6-COOH all trans 28 Linolenic CH3CH2(CH=CH-CH2)3(CH2)6-COOH all cis -11 Elaidolinolenic CH3CH2(CH=CH-CH2)3(CH2)6-COOH all trans 29 Arachidonic CH3(CH2)4(CH=CHCH2)3CH=CH(CH2)3COOH all cis -49.5 15 16 4