What are the low-molecular-weight precursors needed for the de novo biosynthesis of the purine ring, and what is the activated form of a sugar derivative used in both salvage and de novo biosynthetic pathways?
Purine nucleotides are synthesized in the body via de novo synthesis or salvage pathway. Adenine and guanine are the purine nucleotide.
In de novo synthesis, the synthesis process starts with the basic building blocks (small molecules, activated ribose, and amino acids). The precursors required for de novo purine biosynthesis are carbon dioxide, amino acids such as glutamine, glycine, aspartic acid, ATP as an energy source, and activated sugar such as phosphoribosyl diphosphate.
Salvage pathways use nitrogenous bases that are products of previous hydrolysis reactions or purine de novo pathway intermediates as the starting point. Phosphorylation of nucleosides/nucleotides is the primary step of the salvage pathway. Sometimes activated ribose is needed to form nucleoside from a purine base. The precursors for salvage purine synthesis are xanthine, hypoxanthine, urea, nucleosides such as guanosine, adenosine, nucleotides such as GMP, IMP, AMP, and activated sugar such as phosphoribosyl diphosphate.
Step by step
Solved in 3 steps
