Gas-phase conformation-specific photofragmentation of proline-containing peptide ions.
نویسندگان
چکیده
Singly-protonated proline-containing peptides with N-terminal arginine are photodissociated with vacuum ultraviolet (VUV) light in an ESI linear ion trap/orthogonal-TOF (LIT/o-TOF). When proline is the nth residue from the N-terminus, unusual b(n) + 2 and a(n) + 2 ions are observed. Their formation is explained by homolytic cleavage of the C(alpha)-C bond in conjunction with a rearrangement of electrons and an amide hydrogen. The latter is facilitated by a proline-stabilized gas-phase peptide conformation.
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ورودعنوان ژورنال:
- Journal of the American Society for Mass Spectrometry
دوره 21 8 شماره
صفحات -
تاریخ انتشار 2010