Enhanced electron transfer dissociation of peptides modified at C-terminus with fixed charges.
The impact of the conversion of carboxylates in peptides to basic or fixed charge sites on the outcome of electron transfer dissociation (ETD) is evaluated with respect to ETD efficiency and the number of diagnostic sequence ions. Four reagents, including benzylamine (BA), 1-benzylpiperazine (BZP), carboxymethyl trimethylammonium chloride hydrazide (GT), and (2-aminoethyl)trimethylammonium chloride hydrochloride (AETMA), were used for the carboxylate derivatization, with the first two replacing the acidic carboxylate groups with basic functionalities and the latter two introducing fixed charge sites. The ETD efficiencies and Xcorr scores were compared for both nonderivatized and derivatized tryptic and Glu-C peptides from cytochrome c. Derivatization of the carboxylate increases the average charge states, the number of fragment ions, and the dissociation efficiencies of peptides, especially for the fixed charge reagent, AETMA.
Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX 78712, USA.
Byoung Joon
BJ
Ko
Jennifer S
JS
Brodbelt
D000595:Amino Acid Sequence; D002264:Carboxylic Acids / Q000737:chemistry; D045304:Cytochromes c / Q000737:chemistry / Q000378:metabolism; D013058:Mass Spectrometry / Q000379:methods*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism; D020539:Sequence Analysis, Protein; D012697:Serine Endopeptidases / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism
D002264:Carboxylic Acids; D010446:Peptide Fragments; D045304:Cytochromes c; D012697:Serine Endopeptidases; C028344:glutamyl endopeptidase; D014357:Trypsin