Peptide sequencing Flashcards
1
Q
What do impurity derived signals look like
A
Singly charged
2
Q
How are multiply charged ions recognised?
A
Interval between isotopic peaks
3
Q
Do multiply or singly charged ions require more collisional energy
A
Singly
4
Q
Trypsin digestion
A
Digests peptides which then have a minimum of 2 charges (N-terminus and C-terminal lysine or arginine)
5
Q
How is MS used to sequence a peptide
A
Distinctive functional groups on either end with diff masses
6
Q
What is a B-ion
A
N-terminal ion (+1) containing a triply bonded oxygen
7
Q
A-ion
A
B-ion - 28 (CO)
8
Q
Y-ion
A
+19 (OH + 2H)
