1. Associate Professor Department of Biochemistry Lecture-Coenzymes
Dr. Saidunnisa
Associate Professor
Department of Biochemistry
Lecture-Coenzymes

2. Learning Objectives
At the end of the session student shall be able to :
Define and classify coenzymes.
Explain the biochemical role of coenzymes.
Interpret their role in various disorders.

3. Coenzymes
Some enzymes need assistance from other molecules (such as vitamins) in order to facilitate the transformation of chemical reactants into products. These other molecules are collectively referred to as coenzymes.
These are heat stable, low-molecular weight, non protein organic substances function with enzymes in the catalytic processes.

4. Coenzymes are second substrates or co-substrates
Most of them are derivatives of B-complex vitamins.
The functional enzyme is referred to as holoenzyme which is made up of :
Protein part (apoenzyme)
Non protein part (coenzyme)

5. classification
First group-take part in transfer of hydrogen atoms. (oxidoreductases)
eg:-NAD/NADH+H,NADP/NADPH,
FAD/FADH2,FMN/FMNH2
Second group -take part in transferring groups other than hydrogen. eg: PLP,TPP, Biotin, THF, Cobalamin.

6. First group
Oxidative decarboxylation (PDH Complex)

7. First group
First group
Niacin
Oxidation-reduction
Pellagra
NAD/NADP

8. First group Riboflavin (B2) FMN/FAD Oxidation-reduction
Chelosis and glositis

9. Second group
Pyridoxine (B6)
Transamination
PLP
Neurological symptoms

10. Folic acid and B12 Coenzymes
One carbon
Isomerism

11. Oxidative decarboxylation Dry and wet beri beri
Coenzyme
Derived from Vitamin
Physiologic function
deficiency
TPP
Thiamine (B1)
Oxidative decarboxylation
Dry and wet beri beri
FMN/FAD
Riboflavin (B2)
Oxidation-reduction
Chelosis
NAD/NADP
Niacin
Pellagra
PLP
Pyridoxine (B6)
Transamination
Neurological symptoms
Biotin
Carboxylation
Alopecia/dry skin/dermatitis

12. Methyl/deoxyadenosyl cobalamine B12 Isomerism
Coenzyme
Derived from Vitamin
Physiologic function
deficiency
Methyl/deoxyadenosyl cobalamine
B12
Isomerism
Megaloblastic anemia
Tetrahydrofolate (THF)
Folic acid
One carbon metabolism
Microcytic anemia
Coenzyme A
Pantothenic acid
Acyl group
Burning feet syndrome

13. Non-Vitamin coenzymes
Abbreviation
Biochemical Function
Adenosine triphosphate
ATP
Donates phosphate
Cytidine diphosphate
CDP
Required in phospholipid synthesis
Uridine diphosphate
UDP
Required in glycogen synthesis
S-adenosylmethionine
SAM
Donates methyl group
Phosphoadenosine phosphosulfate
PAPS