Skip to main content
. Author manuscript; available in PMC: 2015 Oct 1.
Published in final edited form as: J Am Soc Mass Spectrom. 2014 Jul 24;25(10):1739–1746. doi: 10.1007/s13361-014-0962-4

Figure 1.

Figure 1

(a) Total ion chromatogram after HPLC separation of DEPC-labeled apelin 13. (b) CID spectrum of the (M+2H)2+ ion of the second chromatographic peak from the DEPC-labeled sample of apelin 13, indicating that the N-terminus is modified. (c) CID spectrum of the (M+2H)2+ ion of the third chromatographic peak from the DEPC-labeled sample of apelin 13, indicating that Lys8 is modified. *Interfering ions make assignment of the labeled and unlabeled versions of the y6 ion somewhat ambiguous. (d) CID spectrum of the (M+2H)2+ ion of the fourth chromatographic peak from the DEPC-labeled sample of apelin 13, indicating that His7 is modified.