Exam 22: Protein Synthesis, posttranslational Modification, and Transport

Which molecule contains both an amino acid acceptor stem and an anticodon?

The Shine-Dalgarno sequence of mRNA base pairs with the __________ rRNA within the prokaryote __________ ribosomal subunit.

The antibiotics streptomycin,tetracycline,and chloramphenicol all interfere with

Which sequence is MOST likely to be modified with the fatty acid myristoylate in the ER? (The … represents additional amino acids N-terminal to those shown.)

Which sequence is MOST likely to contain an O-linked oligosaccharide in the ER? (The … represents additional amino acids N-terminal or C-terminal to those shown.)

Radioactively labeled aminoacyl-tRNAs were used in the Nirenberg-Leder experiment to assign triplet codons to specific amino acids.If the aminoacyl-tRNA contains an anticodon of AGG and the mRNA included contains a codon of UCA,where will the radioactivity be located at the end of the experiment? Explain your reasoning.

Differentiate between the mechanisms of type I and type II aminoacyl-tRNA synthetases.

Radioactively labeled aminoacyl-tRNAs were used in the Nirenberg-Leder experiment to assign triplet codons to specific amino acids.Why was this important in the experimental design?

The anticodon of tRNA is made up of __________ bases.

Describe the function of the SRP receptor.

In the image below,which group will be attacked by the nucleophilic amino group of the next amino acid brought into the ribosome?

The rate of translation of an identical mRNA sequence is measured in cells from two different species-E.coli and human.It is found that the rate is slower in E.coli cells.What is a possible reason for this finding?

Compare the chemical structures of puromycin with an aminoacylated tRNA.How do their similarities allow puromycin to function as an antibiotic?

Draw out the peptidyl transferase reaction that is catalyzed by the ribozyme activity of the 23S rRNA in the large ribosomal subunit.

A newly discovered protein is found to be modified by a lipid.Where is this protein most likely located?

Place the following steps in proper order for the translation of a membrane-bound protein. A.GTP binds to SRP. B.Protein synthesis occurs on free ribosome. C.Protein synthesis halts. D.SRP binds to the signal peptide sequence.

Enzyme-mediated protein modification in eukaryotic cells is a means of regulating the activity of the protein.Which of the following is UNLIKELY to result from such a modification?

Which component of the Nirenberg-Leder experiment,that assigned triplet codons to specific amino acids,was radioactively labeled?

Different tRNAs for the same amino acid that bind alternate codons are known as __________ tRNAs.

The tRNA anticodon loop that recognizes the codon UCC could have the sequence