TY - JOUR
T1 - Identification of phosphorylated human peptides by accurate mass measurement alone
AU - Mao, Yuan
AU - Zamdborg, Leonid
AU - Kelleher, Neil L.
AU - Hendrickson, Christopher L.
AU - Marshall, Alan G.
N1 - Funding Information:
We thank Dr. Forest White of the Massachusetts Institute of Technology for helpful discussion. This work was supported by NSF Division of Materials Research through DMR-0654118 , the State of Florida, NIH GM 067193-08 , NIH DA 026672 , and NSF DMS-0800631 .
PY - 2011/12/1
Y1 - 2011/12/1
N2 - At sufficiently high mass accuracy, it is possible to distinguish phosphorylated from unmodified peptides by mass measurement alone. We examine the feasibility of that idea, tested against a library of all possible in silico tryptic digest peptides from the human proteome database. The overlaps between in silico tryptic digest phosphopeptides generated from known phosphorylated proteins (1-12 sites) and all possible unmodified human peptides are considered for assumed mass error ranges of ±10, ±50, ±100, ±1000, and ±10,000 ppb. We find that for mass error ±50 ppb, 95% of all phosphorylated human tryptic peptides can be distinguished from nonmodified peptides by accurate mass alone throughout the entire nominal mass range. We discuss the prospect of on-line LC MS/MS to identify phosphopeptide precursor ions in MS1 for selected dissociation in MS2 to identify the peptide and site(s) of phosphorylation.
AB - At sufficiently high mass accuracy, it is possible to distinguish phosphorylated from unmodified peptides by mass measurement alone. We examine the feasibility of that idea, tested against a library of all possible in silico tryptic digest peptides from the human proteome database. The overlaps between in silico tryptic digest phosphopeptides generated from known phosphorylated proteins (1-12 sites) and all possible unmodified human peptides are considered for assumed mass error ranges of ±10, ±50, ±100, ±1000, and ±10,000 ppb. We find that for mass error ±50 ppb, 95% of all phosphorylated human tryptic peptides can be distinguished from nonmodified peptides by accurate mass alone throughout the entire nominal mass range. We discuss the prospect of on-line LC MS/MS to identify phosphopeptide precursor ions in MS1 for selected dissociation in MS2 to identify the peptide and site(s) of phosphorylation.
KW - Exact mass
KW - FTMS
KW - Fourier transform mass spectrometry
KW - Human proteome
KW - ICR
KW - Ion cyclotron resonance
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U2 - 10.1016/j.ijms.2011.08.006
DO - 10.1016/j.ijms.2011.08.006
M3 - Article
C2 - 22866021
AN - SCOPUS:80955142790
SN - 1387-3806
VL - 308
SP - 357
EP - 361
JO - International Journal of Mass Spectrometry
JF - International Journal of Mass Spectrometry
IS - 2-3
ER -