6. Draw the structure of UMP. Following standard convention, number the ribose a

Question

6. Draw the structure of UMP. Following standard convention, number the ribose and purine rings. Assume you used isotopically labeled 13C enriched aspartate as a starting material for the synthesis of this coupound. Based on your knowledge of the ring assembly identify the carbon atoms in the ring that will be 1C-enriched. 7. Draw the structure of IMP. Following standard convention, number the ribose and purine rings. Assume you used isotopically labeled N enriched glycine asa starting material for the synthesis of this coupound. Based on your knowledge of the ring assembly identify atoms in the ring atom that will be N-enriched nucleotide biosynthesis.

Explanation / Answer

Ans. 8:- Mechanisms involved in the regulation of purine and pyrimidine nucleotide biosynthesis:-

the biosyntheisis of purine and pyrimidine nucleotide are regulated at many steps by feedback inhibition some of the reactions which are regulated by this mechanism are as.

1. one of the most important step is the conversion of 5-phosphoribosyl-1-pyrophosphate (PRPP) into phosphoribosylamine by an enzyme glutamine phosphoribosyl amidotransferase. this enzyme is feedback inhibited by the presence of purine ribonucleotides such as AMP and GMP.

2. IMP is converted to adenylo-succinate whcih inturn is converted to AMP. conversion of IMP to adenylosuccinate is inturn inhibited by AMP, in the second pathway IMP is converted to xanthylate which inturn is converted to GMP but conversion of IMP to xanthylate is inhited by GMP by feedback mechanism.

3. Aspartate transcarbamoylase the enzyme which catalyzes the first step in biosynthesis of pyramidines is inhibited by cytidine triphosphate (CTP) which is a final product of pyrimidine biosynthesis.

Related Questions

Navigate

• Browse (All)
• Browse 6
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.