Concept explainers
Videos
REFLECT AND APPLY A sample of an unknown peptide was divided into two aliquots. One aliquot was treated with trypsin; the other was treated with cyanogen bromide. Given the following sequences (N-terminal to C-terminal) of the resulting fragments, deduce the sequence of the original peptide.
Trypsin treatment
Cyanogen bromide treatment
Trending nowThis is a popular solution!
Chapter 5 Solutions
Biochemistry
- REFLECT AND APPLY Explain why a 50S ribosomal subunit and a 30S ribosomal subunit combine to form a 70S subunit, instead of an 80S subunit.arrow_forwardREFLECT AND APPLY E. coli incorporates deoxyribonucleotides into DNA at a rate of 250 to 1000 bases per second. Using the higher value, translate this into typing speed in words per minute. (Assume five characters per word, using the typing analogy from Question 36.)arrow_forwardREFLECT AND APPLY It is possible for the codons for a single amino acid to have the first two bases in common and to differ in the third base. Why is this experimental observation consistent with the concept of wobble?arrow_forward
- REFLECT AND APPLY Why is a trimming process important in converting precursors of tRNA and rRNA to the active forms?arrow_forwardREFLECT AND APPLY You are studying with a friend who says that the hydrogen-bonded portions of tRNA play no important role in its function. What is your reply?arrow_forwardREFLECT AND APPLY In prokaryotic protein synthesis, N-formylmethionine (fmet) is the first amino acid incorporated, whereas (normal) methionine is incorporated in eukaryotes. The same codon (AUG) serves both. What prevents methionine from being inserted into the beginning and N-formylmethionine in the interior?arrow_forward
- REFLECT AND APPLY List three molecular changes that take place in the processing of eukaryotic mRNA.arrow_forwardREFLECT AND APPLY Would you expect mRNA or rRNA to be degraded more quickly in the cell? Why?arrow_forwardREFLECT AND APPLY Outline a mechanism by which RNA can catalyze its own self-splicing.arrow_forward
- REFLECT AND APPLY (a) How many activation cycles are needed for a protein with 150 amino acids? (b) How many initiation cycles are needed for a protein with 150 amino acids? (c) How many elongation cycles are needed for a protein with 150 amino acids? (d) How many termination cycles are needed for a protein with 150 amino acids?arrow_forwardREFLECT AND APPLY You are in the process of determining the amino acid sequence of a protein and must reconcile contradictory results. In one trial, you determine a sequence with glycine as the N-terminal amino acid and asparagine as the C-terminal amino acid. In another trial, your results indicate phenylalanine as the N-terminal amino acid and alanine as the C-terminal amino acid. How do you reconcile this apparent contradiction?arrow_forwardREFLECT AND APPLY You are in the process of determining the amino acid sequence of a peptide. After trypsin digestion followed by the Edman degradation, you see the following peptide fragments: LeuGlyArgGlySerPheTyrAsnHisSerGluAspMetCysLysThrTyrGluValCysMetHis What is abnormal concerning these results? What might have been the problem that caused it?arrow_forward
BiochemistryBiochemistryISBN:9781305961135Author:Mary K. Campbell, Shawn O. Farrell, Owen M. McDougalPublisher:Cengage Learning