Neurotransmitter Synthesis Pathways

Neurotransmitter Synthesis Pathways

Starting with the precursor substance tyrosine or tryptophan, identify and briefly describe each chemical step required to create each neurotransmitter.

APA

Synthesis of Neurotransmitters from Tyrosine and Tryptophan

From Tyrosine:

1. Tyrosine to L-DOPA:
   • Enzyme: Tyrosine hydroxylase
   • Description: Tyrosine is hydroxylated to L-DOPA (L-3,4-dihydroxyphenylalanine) by the enzyme tyrosine hydroxylase. This is the rate-limiting step in the synthesis of catecholamines.
2. L-DOPA to Dopamine:
   • Enzyme: DOPA decarboxylase (aromatic L-amino acid decarboxylase)
   • Description: L-DOPA is decarboxylated to dopamine by DOPA decarboxylase.
3. Dopamine to Norepinephrine:
   • Enzyme: Dopamine β-hydroxylase
   • Description: Dopamine is hydroxylated to norepinephrine by dopamine β-hydroxylase in the vesicles of nerve cells.
4. Norepinephrine to Epinephrine:
   • Enzyme: Phenylethanolamine N-methyltransferase (PNMT)
   • Description: Norepinephrine is methylated to epinephrine by PNMT, primarily in the adrenal medulla…

Synthesis of Neurotransmitters from Tyrosine and Tryptophan

From Tyrosine:

1. Tyrosine to L-DOPA:
   • Enzyme: Tyrosine hydroxylase
   • Description: Tyrosine is hydroxylated to L-DOPA (L-3,4-dihydroxyphenylalanine) by the enzyme tyrosine hydroxylase. This is the rate-limiting step in the synthesis of catecholamines.
2. L-DOPA to Dopamine:
   • Enzyme: DOPA decarboxylase (aromatic L-amino acid decarboxylase)
   • Description: L-DOPA is decarboxylated to dopamine by DOPA decarboxylase.
3. Dopamine to Norepinephrine:
   • Enzyme: Dopamine β-hydroxylase
   • Description: Dopamine is hydroxylated to norepinephrine by dopamine β-hydroxylase in the vesicles of nerve cells.
4. Norepinephrine to Epinephrine:
   • Enzyme: Phenylethanolamine N-methyltransferase (PNMT)
   • Description: Norepinephrine is methylated to epinephrine by PNMT, primarily in the adrenal medulla…

Synthesis of Neurotransmitters from Tyrosine and Tryptophan

From Tyrosine:

1. Tyrosine to L-DOPA:
   • Enzyme: Tyrosine hydroxylase
   • Description: Tyrosine is hydroxylated to L-DOPA (L-3,4-dihydroxyphenylalanine) by the enzyme tyrosine hydroxylase. This is the rate-limiting step in the synthesis of catecholamines.
2. L-DOPA to Dopamine:
   • Enzyme: DOPA decarboxylase (aromatic L-amino acid decarboxylase)
   • Description: L-DOPA is decarboxylated to dopamine by DOPA decarboxylase.
3. Dopamine to Norepinephrine:
   • Enzyme: Dopamine β-hydroxylase
   • Description: Dopamine is hydroxylated to norepinephrine by dopamine β-hydroxylase in the vesicles of nerve cells. (Neurotransmitter Synthesis Pathways)
4. Norepinephrine to Epinephrine:
   • Enzyme: Phenylethanolamine N-methyltransferase (PNMT)
   • Description: Norepinephrine is methylated to epinephrine by PNMT, primarily in the adrenal medulla…