Question

Describe the reactions that convert IMP to ATP and GTP.

Short answer

The inosine monophosphate (IMP) first converts into AMP, GMP, and then to the adenosine triphosphate (ATP) and guanosine triphosphate (GTP), respectively, using various enzymes catalyzing the reactions.

Step-by-step solution

Reaction of inosine monophosphate (IMP) to form adenosine triphosphate (ATP)

Inosine monophosphate (IMP) is rapidly converted to adenosine monophosphate (AMP) and guanosine monophosphate (GMP).

In this reaction, aspartate’s amino group reacts with Inosine monophosphate (IMP) in a reaction, hydrolysis of GTP to form adenylosuccinate. Then the catalyst adenylosuccinate lyase eliminates the fumarate component from adenylosuccinate to form adenosine monophosphate (AMP). The AMP is then phosphorylated with the help of an enzyme adenylate kinase to form ADP, and the ADP compound forms the adenosine triphosphate (ATP) compound.

Reaction of inosine monophosphate (IMP) to form the guanosine triphosphate (GTP) compound.

In this reaction, inosine monophosphate (IMP) is dehydrogenated by the reduction of $NA{D}^{+}$to form xanthosine monophosphate (XMP) in the presence of ribonucleotide base xanthine. XMP then forms guanosine monophosphate (GMP) by the transfer of glutamine amide nitrogen. Then the hydrolysis takes place on ATP to ${\text{AMP + PP}}_{\text{i}}$form the guanosine monophosphate (GMP). Then the guanosine monophosphate (GMP) forms the GDP, and then GDP is converted into guanosine triphosphate (GTP) with the help of the enzyme guanylate kinase.