Aulani "Biokimia" Presentation 3 Carbohydrate Metabolism Carbohydrate Metabolism Aulanni’am Biochemistry Laboratory Chemistry Departement Brawijaya University

Aulani "Biokimia" Presentation 3

Carbohydrates Carbohydrates are the most abundant organic molecules in nature Carbohydrates are the most abundant organic molecules in nature Photosynthesis energy stored in carbohydrates; Photosynthesis energy stored in carbohydrates; Carbohydrates are the metabolic precursors of all other biomolecules; Carbohydrates are the metabolic precursors of all other biomolecules; Important component of cell structures; Important component of cell structures; Important function in cell-cell recognition; Important function in cell-cell recognition; Carbohydrate chemistry: Carbohydrate chemistry: Contains at least one asymmetric carbon center; Contains at least one asymmetric carbon center; Favorable cyclic structures; Favorable cyclic structures; Able to form polymers Able to form polymers

Aulani "Biokimia" Presentation 3 Carbohydrate Nomenclature Carbohydrate Classes: Carbohydrate Classes: Monosaccharides (CH 2 O)n Monosaccharides (CH 2 O)n Simple sugars, can not be broken down further; Simple sugars, can not be broken down further; Oligosaccharides Oligosaccharides Few simple sugars (2-6). Few simple sugars (2-6). Polysaccharides Polysaccharides Polymers of monosaccharides Polymers of monosaccharides

Aulani "Biokimia" Presentation 3 Carbohydrate Nomenclature Monosaccharide (carbon numbers 3-7) Monosaccharide (carbon numbers 3-7) Aldoses Aldoses Contain aldehyde Contain aldehyde Name: aldo-#-oses (e.g., aldohexoses) Name: aldo-#-oses (e.g., aldohexoses) Memorize all aldoses in Figure ? Ketoses Ketoses Contain ketones Contain ketones Name: keto-#-oses (ketohexoses ) Name: keto-#-oses (ketohexoses )

Aulani "Biokimia" Presentation 3 Monosaccharide Structures Conformation of monosaccharide Conformation of glucose

Aulani "Biokimia" Presentation 3 Disaccharides Simplest oligosaccharides; Contain two monosaccharides linked by a glycosidic bond; The free anomeric carbon is called reducing end;. The linkage carbon on the first sugar is always C-1. So disaccharides can be named as sugar- (a,b)-1,#-sugar, where a or b depends on the anomeric structure of the first sugar. For example, Maltose is glucose-a-1,4-glucose.

Aulani "Biokimia" Presentation 3 Structures of Disaccharides Note the linkage and reducing ends

Aulani "Biokimia" Presentation 3 Polysacchrides Also called glycans; Also called glycans; Starch and glycogen are storage molecules; Starch and glycogen are storage molecules; Chitin and cellulose are structural molecules; Chitin and cellulose are structural molecules; Cell surface polysaccharides are recognition molecules. Cell surface polysaccharides are recognition molecules. Glucose is the monosaccharides of the following polysacchrides with different linkages and banches a(1,4), starch (more branch) a(1,4), glycogen (less branch) a(1,6), dextran (chromatography resins) b(1,4), cellulose (cell walls of all plants) b(1,4), Chitin similar to cellulose, but C2-OH is replaced by –NHCOCH 3 (found in exoskeletons of crustaceans, insects, spiders)

Aulani "Biokimia" Presentation 3 Overview of Glucose Catabolism Cells catabolize organic molecules and make ATP two ways: Substrate-Level Phosphorylation Glycolysis Krebs (TCA) Cycle Oxidative Phosphorylation Electron Transport Chain

Aulani "Biokimia" Presentation 3 Overview of Glucose Catabolism

Aulani "Biokimia" Presentation 3 Overview of Glucose Catabolism Glycolysis Biochemical pathway that produces ATP by substrate-level phosphorylation. Yields a net of two ATP molecules for each molecule of glucose catabolized. Every living creature is capable of carrying out glycolysis. Most present-day organisms can extract considerably more energy from glucose through aerobic respiration. Net reaction

Aulani "Biokimia" Presentation 3 Glucose priming

Aulani "Biokimia" Presentation 3 Cleavage and rearrangement PP

Aulani "Biokimia" Presentation 3

Krebs Cycle After pyruvate has been oxidized, acetyl- CoA feeds into the Krebs cycle. Krebs cycle is the next step of oxidative respiration and takes place in mitochondria. Occurs in three stages: Acetyl-CoA binds a four- carbon molecule and produces a six-carbon molecule. Two carbons are removed as CO 2. Four-carbon starting material is regenerated. Cycle is also known as Tricarboxylic acid (TCA) cycle Citric acid cycle citric acid

Aulani "Biokimia" Presentation 3 Aerobic Respiration The pyruvic acid formed by glycolysis enters interior of mitochondria. The pyruvic acid formed by glycolysis enters interior of mitochondria. Converted by coenzyme A to 2 molecules of acetyl CoA and 2 C0 2. Converted by coenzyme A to 2 molecules of acetyl CoA and 2 C0 2. Acetyl CoA serves as substrate for mitochondrial enzymes in the aerobic pathway. Acetyl CoA serves as substrate for mitochondrial enzymes in the aerobic pathway.

Aulani "Biokimia" Presentation 3

Krebs Cycle Generates two ATP molecules per molecule of glucose. Generates many energized electrons which can be directed to the electron transport chain to drive synthesis of more ATP: 6 NADH per molecule of glucose 2 FADH 2 per molecule of glucose

Aulani "Biokimia" Presentation 3

Glycolysis

Aulani "Biokimia" Presentation 3 KREBS CYCLE KREBS CYCLE Takes place in Mitochondrion when oxygen is present Pyruvic acid from glycolysis is trimmed to a 2 carbon compound Remaining carbon from glucose => CO 2 Hydrogens transferred NAD+ => NADH FAD => FADH Products of kreb cycle 3 NADHs 1 FADH 2 2 ATP

Aulani "Biokimia" Presentation 3 The Cori Cycle The reconversion of lactic acid to pyruvate sees the removal of fatiguing lactate from the site of production. This forms the theoretical basis for the cool-down. As the glycolysis pathway is reversible lactic acid can eventually be anabolised into glucose and stored in the liver, muscles or blood.

Aulani "Biokimia" Presentation 3 Electron Transport System

Aulani "Biokimia" Presentation 3 Electron Transport System

Aulani "Biokimia" Presentation 3 Energy Capacity to perform work. Capacity to perform work. Two examples: Two examples: 1.Kinetic energy 2.Potential energy

Aulani "Biokimia" Presentation 3 Kinetic Energy Energy in the process of doing work. Energy in the process of doing work. Energy of motion. Energy of motion. Examples: Examples: 1.Heat 2.Light energy SUN

Aulani "Biokimia" Presentation 3 Potential Energy Energy that matter occupies because of it’s location, arrangement, or position. Energy of position. Examples: 1.Water behind a dam 2.Chemical energy (gas) GAS

Aulani "Biokimia" Presentation 3 Answer: adenosine triphosphate (ATP) adenosine triphosphate (ATP) Components: Components: 1.adenine:nitrogenous base 2.ribose:five carbon sugar 3.phosphate group: chain of three ribose adenine PPP phosphate group Question: What is ATP? What is ATP?

Aulani "Biokimia" Presentation 3 Answer: Works by the direct chemical transfer of a phosphate group. Works by the direct chemical transfer of a phosphate group. This is called “phosphorylation”. This is called “phosphorylation”. The exergonic hydrolysis of ATP is coupled with the endergonic processes by transferring a phosphate group to another molecule. The exergonic hydrolysis of ATP is coupled with the endergonic processes by transferring a phosphate group to another molecule.

Aulani "Biokimia" Presentation 3 Hydrolysis of ATP ATP + H 2 O  ADP + P (exergonic) ATP + H 2 O  ADP + P (exergonic) Hydrolysis (add water) PPP Adenosine triphosphate (ATP) PP P + Adenosine diphosphate (ADP )

Aulani "Biokimia" Presentation 3 Dehydration of ATP ADP + P  ATP + H 2 O (endergonic) Dehydration synthesis (remove water ) (remove water ) PPP Adenosine triphosphate (ATP) PP P + Adenosine diphosphate (ADP )

Aulani "Biokimia" Presentation 3