De novo synthesis of purine nucleotides is a complex biochemical pathway that involves multiple enzymes and intermediate compounds. Purine nucleotides are essential building blocks for DNA and RNA synthesis, as well as for various biological processes in the cell. The de novo synthesis pathway is responsible for the production of purine nucleotides from simple precursor molecules, such as amino acids and ribose-5-phosphate.
The de novo synthesis of purine nucleotides can be divided into multiple steps, each catalyzed by specific enzymes. The pathway starts with the conversion of phosphoribosylpyrophosphate (PRPP) to 5-phosphoribosylamine, which is the first committed step in purine biosynthesis. This reaction is catalyzed by the enzyme amidophosphoribosyltransferase (ATase), also known as phosphoribosylaminoimidazole synthetase (PAT).
The next step in the pathway involves the formation of 5-phosphoribosylglycinamide from 5-phosphoribosylamine. This reaction is catalyzed by the enzyme phosphoribosylamine-glycine ligase (GART), which is a multifunctional enzyme that also catalyzes the subsequent steps in the pathway. The third step in purine biosynthesis is the conversion of 5-phosphoribosylglycinamide to 5-phosphoribosylglycinamide formyltransferase (GAR transformylase), which is a key regulatory enzyme in the pathway.
The fourth step in purine biosynthesis is the conversion of 5-phosphoribosylglycinamide formyltransferase to 5-phosphoribosyl-5-aminoimidazole (AIR) by the enzyme phosphoribosylformylglycinamidine cyclo-ligase (FGAM synthase). The fifth step in the pathway involves the conversion of AIR to 5-phosphoribosyl-4-carboxamide-5-aminoimidazole (CAIR) by the enzyme phosphoribosylaminoimidazole carboxylase (PAICS).
The next steps in purine biosynthesis involve the formation of the purine ring system from CAIR. The sixth step in the pathway is the conversion of CAIR to aminoimidazole carboxamide ribonucleotide (AICAR) by the enzyme phosphoribosylaminoimidazole carboxylase (PAICS). The seventh step in purine biosynthesis involves the conversion of AICAR to 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) by the enzyme AICAR transformylase.
The last steps in purine biosynthesis involve the formation of inosine monophosphate (IMP) from AICAR. The eighth step in the pathway is the conversion of AICAR to 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) by the enzyme IMP cyclohydrolase. The ninth and final step in purine biosynthesis is the conversion of IMP to adenosine monophosphate (AMP) and guanosine monophosphate (GMP) in a series of reactions catalyzed by multiple enzymes.
Overall, the de novo synthesis of purine nucleotides is a highly regulated and complex pathway that involves multiple enzymes and intermediate compounds. The pathway is essential for the production of purine nucleotides, which are crucial for DNA and RNA synthesis, as well as for various biological processes in the cell. Understanding the biochemical mechanisms involved in purine biosynthesis is important for the development of new drugs to target specific enzymes in the pathway and for the treatment of diseases related to purine metabolism disorders.
De novo synthesis of purine nucleotides. provide every information involved in the synthesis, also enzymes involved in the process and the information must be more than 4 pages.
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