Adenosine Monophosphate (AMP)

AMP is a common intermediate in metabolism involving ATP.

AMP is produced as a result of energy-yielding metabolism of ATP in three ways:

A. By hydrolysis of a pyrophosphate from ATP (one example is shown in reaction 1 below).

B. By transfer of a phosphate from ADP (reaction 2 below).

C. By transfer of a pyrophosophate from ATP to another metabolite (reaction 6 below)

AMP is also an intermediate in de novo synthesis of ATP (reaction 3 below) and salvage synthesis of ATP (reactions 4, 5, and 8 below). AMP is an allosteric activator of glycogen phosphorylase b, and phosphofructokinase, as well as an allosteric inhibitor of fructose-1,6-bisphosphatase and adenylosuccinate synthetase. AMP is also an allosteric inhibitor of glutamine synthetase, an enzyme with a central role in nitrogen metabolism in the cell.

Selected reactions involving AMP

> 1. Fatty acid + ATP + CoASH <=> Fatty acyl-CoA + AMP + PPi (catalyzed by Fatty acyl-CoA Ligase).

> 2. 2 ADP <=> ATP + AMP (catalyzed by Adenylate Kinase)

> 3. Adenylosuccinate <=> Fumarate + AMP (catalyzed by Adenylosuccinate Lyase)

> 4. PRPP + Adenine <=> AMP + PPi (catalyzed by Phosphoribosyltransferase)

> 5. ATP + Ribose-5-Phosphate <=> PRPP + AMP (catalyzed by PRPP Synthetase)

> 6. AMP + H 2O <=> NH 4+ + IMP (catalyzed by AMP Deaminase)

See also: ATP, ADP, cAMP, AMP-Dependent Protein Kinase