• Glycolysis is a process of conversion of glucose into pyruvate by a series of intermediate metabolites.
• Glycolysis is a part of cellular respiration
• Each chemical modification is performed by a different enzyme.
• In this process, ATP is formed in the cytoplasm.
• ATP = energy.

Steps of the process

Step 1:

• Phosphate is transferred from ATP to glucose, making Glucose-6-phosphate.
• Glucose-6-phosphate is more reactive than glucose.
• Reaction completed by the enzyme Hexokinase.

Step 2:

• Glucose-6-phosphate is converted into its isomeric form (fructose 6-phosphate).
• The reaction is carried out by glucose-6-phosphate isomerase.

Step 3:

• A phosphate group from ATP is transferred to fructose 1,6-biphosphate
• The reaction is catalyzed by the enzyme phosphofructokinase.

Step 4:

• Fructose 1,6-biphosphate splits to form two molecules, three-carbon sugar.

DHCP and glyceraldehyde-3-phosphate

• Both are isomers of each other.
• The reaction is completed by aldolase

Step 5:

• DHCP and glyceraldehyde-3-phosphate are interconvertible.
• The enzyme used in the reaction: triose isomerase

Step 6:

• Molecules from reaction 5 one molecule get converted to 1-3, diphosphoglyceric acid
• The reaction is carried out by Phosphoglyceric dehydrogenase.

Step 7:

• 1-3, diphosphoglyceric acid is converted to 3 Phosphoglyceric acid.
• The reaction is completed by the enzyme 3-phosphoglyceric 1-kinase.
• in-between reaction 6-7 2 molecules of ADP gets converted into 2ATP.

Step 8:

• 3-phosphoglyceric acid is converted to 2-phosphoglyceric acid.
• The used enzyme in the reaction is phosphoglyceromutase.

Step 9:

• 2-phopshoglyceric acid is converted into phospho-enol pyruvate.
• By the enzyme Enolase.

Step 10:

• PEP (phospho-enol-pyruvate) gets converted to pyruvic acid.
• By the enzyme pyruvic kinase.
• 2ADP    —> 2ATP

 

Structure of ATP

• ATP is the Adenosine triphosphate.
• It contains an adenosine base.
• A pentose-sugar.
• And 3 molecule of phosphate (alpha, beta, and gamma phosphate groups).
• A molecule of ATP provides us chemical energy.
• Energy stored in bonds
• When a molecule of ATP is breaking down it produce ADP and energy

 

   QUESTION:    

1. ATP is nucleotide or nucleoside?
2. Which bond in ATP stores energy?
3. The amount of energy released.?
4.  Structure of NAD and NADH?

 

Function of NAD

• Nicotinamide adenine dinucleotide
• NAD is a coenzyme.
• Can be found in all the living cells.
• NAD is a dinucleotide.
• It consists of two nucleotides which are joined by phosphate groups present.
• Out of two nucleotides, one nucleotide has an adenine base, and the other one having nicotinamide.
• NAD exists in two forms,
• An oxidized and reduced form (NAD+)
• In metabolism NAD involved in a redox reaction.
• Carries an electron from one reaction to another reaction.
• That’s why it’s found in two forms, NAD+ is an oxidizing agent it accepts electron and became reduced.
• The transfer of electron is a main function of NAD.
• NAD acts as cofactor in redox reactions.
• Roles are involved in: Energy metabolism, mitochondrial functions.
• Having a deficiency can cause:

Deacceleration of glycolysis and Krebs’s cycle

Function od NADP

• Nicotinamide Adenine Diphosphate
• NADH plays an important role in metabolism.
• NADPH is a reduced form of NADP
• It differs from NAD by the presence of an additional PO₄^–
• NADP(H) provides reducing Equivalents for biosynthetic reactions.
• Oxidation-reduction involved in protecting against the toxicity of reactive oxygen species.
• As a Co-Enzyme in anabolic reaction
• As a regenerator of reduced glutathione.
• The deficiency of NAPD can lead to higher sensibility to oxidative damage.