Flashcards in Biochem High Yield Deck (80)
What is the mechanism of leflunomide?
inhibits dihydrofolate dehydrogenase
What is the mechanism for mycophenolate and ribavirin?
Inhibits IMP dehydrogenase
What is the mechanism of hydroxyurea?
inhibits ribonucleotide reductase
What is teh mecahnism of 6MP?
inhibits de novo purine synthesis
What is the mechanism of 5- FU?
inhibits thymidylate synthase
What is the mechanism of methotrexate and methoprim and pyrimethamine?
inhibits dehydrofolate reductase
"defective purine salvage due to absent HGPRT"
Lesch- Nyhan syndrome
What is the function of HGPRT?
Converts hypoxanthine to IMP and guanine to GMP
What are teh 5 symptoms of Lesch- Nyhan syndrome?
Aggression/ self mutilation
Enzyme that unwinds prokaryptic DNA for repliction?
What is the function of DNA topoisomerase?
creates single or double stranded break
Synthesis and proofreading directions of bacterial DNA polymerase III?
What degrades RNA primer in DNA of bacteira?
DNA polymerase I
What enzyme joins okazaki fragment?
"mutation that causes a changes amino acid"
"mutation that leads to early stop codon"
What repair mechanism is defective in xeroderma pigmentosum?
Nucleotide excision repair (prevents repair of pyrimidine dimers from UV light exposure)
What repair mechanism is defective in HNPCC?
What DNA repair mechanism is defective in ataxia telangiectasia?
Nonhomologous end joining
Name 3 stop codons?
What binds the promoter region in eukaryotes for gene expression?
RNA polymerase II
What does Amanita phalloides (death cap mushroom) inhibit?
RNA polymerase II (eukaryotes)
What post transcriptional alterations occur in the nucleus?
1- 5' cap
2- Poly A tail
Splicing of introns
What molecule is responsible for splicing of pre-mRNA?
What is the T arm on tRNA necessary for?
tRNA ribosomal binding
What is the anti-codon loop needed for?
Binding the codon on the mRNA
Where does the AA bind tRNA?
3' end (ACC)
What is the D arm of tRNA needed for?
recognized by aminoacul- tRNA synthase
What is the initator tRNA?