Podcast
Questions and Answers
What is the biological function of DNA topoisomerases?
What is the biological function of DNA topoisomerases?
- Methylating deoxyuridine monophosphate to give dTMP (correct)
- Modulating drug treatment for cancer
- Catalyzing the synthesis of thymine and purine bases
- Acting as targets for cancer drug development
What is the essential role of folinic acids in the synthesis of thymine and purine bases?
What is the essential role of folinic acids in the synthesis of thymine and purine bases?
- Preventing cell death
- Accelerating cell division
- Catalyzing DNA synthesis (correct)
- Increasing the affinity of methotrexate to enzymes
How do classical antifolates differ from nonclassical antifolates?
How do classical antifolates differ from nonclassical antifolates?
- Presence of glutamic acid side chains vs. presence of lipophilic substituents (correct)
- Inhibition of thymidylate synthase vs. inhibition of DHFR
- Folic acid analogues vs. natural ligand replacements
- Stronger affinity to enzyme vs. lack of hydrogen bonds
Why does Aminopterine have a stronger affinity to enzymes compared to natural substrate folic acid?
Why does Aminopterine have a stronger affinity to enzymes compared to natural substrate folic acid?
What is the main consequence of DHFR inhibition?
What is the main consequence of DHFR inhibition?
Which statement about 5-Fluorouracil (5FU) is correct?
Which statement about 5-Fluorouracil (5FU) is correct?
What is the lead structure of Topoisomerase I inhibitors?
What is the lead structure of Topoisomerase I inhibitors?
How does Topoisomerase I work to release supercoiled tension in DNA?
How does Topoisomerase I work to release supercoiled tension in DNA?
Which chemical modification was done to improve the water solubility of camptothecin, resulting in topotecan?
Which chemical modification was done to improve the water solubility of camptothecin, resulting in topotecan?
What is the mechanism of action of camptothecin derivatives like irinotecan in inhibiting Topoisomerase I?
What is the mechanism of action of camptothecin derivatives like irinotecan in inhibiting Topoisomerase I?
What is the active metabolite of irinotecan, a derivative of camptothecin?
What is the active metabolite of irinotecan, a derivative of camptothecin?
Which type of cancer is topotecan, a derivative of camptothecin, used to treat?
Which type of cancer is topotecan, a derivative of camptothecin, used to treat?
What is the primary reason for the absence of dTMP in the fluorinated ternary complex?
What is the primary reason for the absence of dTMP in the fluorinated ternary complex?
Which type of DNA topoisomerase enzyme breaks both strands and requires ATP for full activity?
Which type of DNA topoisomerase enzyme breaks both strands and requires ATP for full activity?
What is the significance of the 'cleavable complex' in the action of DNA topoisomerase enzymes?
What is the significance of the 'cleavable complex' in the action of DNA topoisomerase enzymes?
What is the main function of DNA topoisomerases in DNA transcription and replication?
What is the main function of DNA topoisomerases in DNA transcription and replication?
What is the primary mechanism by which 5-fluorouracil acts as an anticancer drug?
What is the primary mechanism by which 5-fluorouracil acts as an anticancer drug?
What is the significance of the 'topo-isomers' in the context of DNA topology?
What is the significance of the 'topo-isomers' in the context of DNA topology?
What is the role of tyrosine residues in the action of DNA topoisomerase enzymes?
What is the role of tyrosine residues in the action of DNA topoisomerase enzymes?
What is the primary mechanism by which DNA topoisomerase enzymes regulate the 3D geometry of DNA?
What is the primary mechanism by which DNA topoisomerase enzymes regulate the 3D geometry of DNA?
What is the primary role of oral prodrugs in the context of 5-fluorouracil treatment?
What is the primary role of oral prodrugs in the context of 5-fluorouracil treatment?
What is the primary role of DNA topoisomerase enzymes in DNA transcription?
What is the primary role of DNA topoisomerase enzymes in DNA transcription?
What is the mechanism of action of 5-FU in inhibiting DNA synthesis?
What is the mechanism of action of 5-FU in inhibiting DNA synthesis?
Why does 5-FU show selectivity for cancer cells over normal skin cells?
Why does 5-FU show selectivity for cancer cells over normal skin cells?
Which step in the dTMP synthesis pathway involves the breaking of the imidazolidine ring and release of N10 from the co-factor?
Which step in the dTMP synthesis pathway involves the breaking of the imidazolidine ring and release of N10 from the co-factor?
Why does the fluorinated ternary complex formed by 5-FU prevent the breakdown into dTMP?
Why does the fluorinated ternary complex formed by 5-FU prevent the breakdown into dTMP?
What is the primary target of methotrexate's mechanism of action?
What is the primary target of methotrexate's mechanism of action?
In what way does methotrexate differ from aminopterine in its pharmacokinetic properties?
In what way does methotrexate differ from aminopterine in its pharmacokinetic properties?
What role does co-factor N5, N10-methylene FH4 play in the dTMP synthesis pathway?
What role does co-factor N5, N10-methylene FH4 play in the dTMP synthesis pathway?
What attribute of C6 position on FdUMP makes it more electrophilic than the normal substrate?
What attribute of C6 position on FdUMP makes it more electrophilic than the normal substrate?
