Abstract

MS/MS spectra were recorded for the ions of [Glu1]-fibrinopeptide produced upon radiolysis in O16 and O18-labeled water that correspond to unmodified peptide, and peptide modified with O16 and O18. These spectra reveal that phenylalanine residues are modified with both O16 and O18 as indicated by the shift in m/z values for the y-type ions y4 through y11 and N-terminal b-type ions b10 through b13. Both phenylalanine residues are partially modified as indicated by the presence of the y4 and b10 fragments that do not contain O16/ O18 in spectra for modified peptide. Mass spectrometry studies of the radiolysis products of other peptides in O18-labeled water reveal that methionine reacts with hydroxyl radicals and oxygen while phenylalanine and tyrosine residues react predominantly with hydroxyl radicals. Proline is oxidized solely by molecular oxygen to produce +14 and +16u products presumably through radical ion formation by hydrated electrons, followed by reactions with O2. The loss of molecular hydrogen to a ketone accounts for the formation of the +14 radiolyzed product. Tryptophan shows multiple oxidation to form products at +16 and +32u. Cysteine is shown to incorporate up to three oxygens. Radiolysis in O18-labeled water revealed that hydroxyl radicals and molecular oxygen both compete in the formation of these products.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR001633-19
Application #
6491437
Study Section
Project Start
2001-09-01
Project End
2002-08-31
Budget Start
Budget End
Support Year
19
Fiscal Year
2001
Total Cost
Indirect Cost

  Institution

Name
Albert Einstein College of Medicine
Department
Type
DUNS #
009095365
City
Bronx
State
NY
Country
United States
Zip Code
10461

  Publications

Vongsvivut, Jitraporn; Fernandez, Jason; Ekgasit, Sanong et al. (2004) Characterization of supported cylinder-planar germanium waveguide sensors with synchrotron infrared radiation. Appl Spectrosc 58:143-51
Masip, Lluis; Pan, Jonathan L; Haldar, Suranjana et al. (2004) An engineered pathway for the formation of protein disulfide bonds. Science 303:1185-9
Huang, Raymond Y; Miller, Lisa M; Carlson, Cathy S et al. (2003) In situ chemistry of osteoporosis revealed by synchrotron infrared microspectroscopy. Bone 33:514-21
Rashidzadeh, Hassan; Khrapunov, Sergei; Chance, Mark R et al. (2003) Solution structure and interdomain interactions of the Saccharomyces cerevisiae ""TATA binding protein"" (TBP) probed by radiolytic protein footprinting. Biochemistry 42:3655-65
Uchida, Takeshi; Takamoto, Keiji; He, Qin et al. (2003) Multiple monovalent ion-dependent pathways for the folding of the L-21 Tetrahymena thermophila ribozyme. J Mol Biol 328:463-78
Taylor, Colleen M; Watton, Stephen P; Bryngelson, Peter A et al. (2003) Inner-sphere complexation of cobalt(II) 2,9-dimethyl-1,10-phenanthroline ([Co(neo)]2+) with commercial and sol-gel derived silica gel surfaces. Inorg Chem 42:312-20
Dhavan, Gauri M; Crothers, Donald M; Chance, Mark R et al. (2002) Concerted binding and bending of DNA by Escherichia coli integration host factor. J Mol Biol 315:1027-37
Uchida, Takeshi; He, Qin; Ralston, Corie Y et al. (2002) Linkage of monovalent and divalent ion binding in the folding of the P4-P6 domain of the Tetrahymena ribozyme. Biochemistry 41:5799-806
Tang, Qun; Carrington, Paul E; Horng, Yih-Chern et al. (2002) X-ray absorption and resonance Raman studies of methyl-coenzyme M reductase indicating that ligand exchange and macrocycle reduction accompany reductive activation. J Am Chem Soc 124:13242-56
Guan, Jing-Qu; Vorobiev, Sergeui; Almo, Steven C et al. (2002) Mapping the G-actin binding surface of cofilin using synchrotron protein footprinting. Biochemistry 41:5765-75

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