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What is the function of aqueous acid in the Edman degradation process?
After identifying the first N-terminal residue as glycine, what is the next step in Edman degradation?
What is the primary role of the Edman degradation sequinator in peptide sequencing?
A peptide sequence is determined using Edman degradation and HPLC. If the chromatogram shows peaks for alanine, glycine, and valine, what is the sequence from the N-terminal to the C-terminal?
In which direction is the sequence read in mass spectrometry?
A protein with 100 amino acids is sequenced using Edman degradation. Explain how the accumulation of unwanted PTH amino acid side products affects the sequencing accuracy.
Why is it important to maintain a cumulative yield above 60% in Edman degradation?
Determine the cumulative yield after 40 cycles with a reaction efficiency of 96%.
Why is it challenging to determine the order of peptide fragments in the original protein sequence after cleavage?
What is the role of chymotrypsin in protein sequencing?
What is the rationale for starting with the longest fragment when ordering peptide fragments?
Which amino acid residues does trypsin specifically cleave?
What is the significance of identifying the use of hydrazine in a peptide sequencing problem?
How can you identify the N-terminal fragment in a peptide sequence cleaved by pepsin?