The α-amino group of the new amino acyl tRNA in the A site carries out a nucleophilic attack on the esterified carboxyl group of the peptidyl tRNA occupying the P site. This reaction is catalysed by (A) DNA polymerase (B) RNA polymerase (C) Peptidyl transferase (D) DNA ligase

1 Answer

Answer :

Answer :  C

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Description : The nucleophilic attack on the esterified carboxyl group of the peptidyl-tRNA occupying the P site and the α-amino group of the new amino acyl tRNA, the number of ATP required by the amino acid on the charged tRNA is (A) Zero (B) One (C) Two (D) Four

Last Answer : Answer : A

Description : The enzyme amino acyl tRNA synthetase is involved in (A) Dissociation of discharged tRNA from 80S ribosome (B) Charging of tRNA with specific amino acids (C) Termination of protein synthesis (D) Nucleophilic attack on esterified carboxyl group of peptidyl tRNA

Last Answer : Answer : B

Description : Which of the following molecule catalyzes the transpeptidation reaction? A.RNA polymerase B.Peptidyl transferase C.DNA ligase D.DNA polymerase

Last Answer : B.Peptidyl transferase

Description : Erythromycin binds to 50 S ribosomal sub unit and (A) Inhibits binding of amino acyl tRNA (B) Inhibits Peptidyl transferase activity (C) Inhibits translocation (D) Causes premature chain termination

Last Answer : Answer : C

Description : Peptidyl transferase activity is present in (A) 40 S ribosomal subunit (B) 60 S ribosomal subunit (C) eEF-2 (D) Amino acyl tRNA

Last Answer : Answer : B

Description : Which of the following step of translation does not consume a high energy phosphate bond? (a) Peptidyl transferase reaction (b) Aminoacyl tRNA binding to A-site (c) Translocation (d) Amino acid activation

Last Answer : (b) Aminoacyl tRNA binding to A-site

Description : Which of the following step of translation does not consume a high energy phosphate bond? (a) Peptidyl transferase reaction (b) Aminoacyl tRNA binding to A-site (c) Translocation (d) Amino acid activation

Last Answer : (a) Peptidyl transferase reaction

Description : Translocation of the newly formed peptidyl tRNA at the A site into the empty P site involves (A) EF-II, GTP (B) EF-I, GTP (C) EF-I, GDP (D) Peptidyl transferase, GTP

Last Answer : Answer : A

Description : The mechanism of antibacterial action of tetracycline involves (a) Binding to a component of the 50S ribosomal subunit (b) Inhibition of translocase activity (c) Blockade of binding of ... (d) Selective inhibition of ribosomal peptidyl transferases (e) Inhibition of DNA-dependent RNA polymerase

Last Answer : Ans: C

Description : All the following statements about charging of tRNA are correct except (A) It is catalysed by amino acyl tRNA synthetase (B) ATP is converted into ADP and Pi in this reaction (C) The enzyme recognizes the tRNA and the amino acid (D) There is a separate enzyme for each tRNA

Last Answer : Answer : B

Description : The newly entering amino acyl tRNA into A site requires (A) EF-II (B) Ribosomal RNA (C) mRNA (D) EF-I

Last Answer : Answer : D

Description : Which binding is inhibited by pactamycin? A- Aminoacyl-tRNA to the A-site of 30S subunit B- Initiator-tRNA to 30S/40S initiation complexes C- Peptidyl t-RNA to the 50S subunit D- Formation of peptide bond in P site

Last Answer : Initiator-tRNA to 30S/40S initiation complexes

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Last Answer : Answer : C

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Last Answer : Answer : D

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Last Answer : Answer : A

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Last Answer : Peptidlytransferase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymerase B- .Peptidyltransferase C- DNA ligase D- .DNA polymerase

Last Answer : .Peptidyltransferase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA Polymerase B- Peptidlytransferase C- DNA ligase D- DNA polymerase

Last Answer : Peptidlytransferase

Description : Which of the following molecule catalyzes the transpeptidation reaction? A- RNA polymerase B- .Peptidyltransferase C- DNA ligase D- .DNA polymerase

Last Answer : .Peptidyltransferase

Description : In biotin-containing enzymes, the biotin is bound to the enzyme by (A) An amide linkage to carboxyl group of glutamine (B) A covalent bond with CO2 (C) An amide linkage to an amino group of lysine (D) An amide linkage to α-carboxyl group of protein

Last Answer : Answer : C

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Last Answer : It blocks the binding of amino-acyl tRNA to the A site of ribosomes

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Last Answer : It blocks the binding of amino-acyl tRNA to the A site of ribosomes

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Last Answer : Answer : A

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Last Answer : Answer : C

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