Lysozyme oxidation by singlet molecular oxygen: Peptide characterization using [O-18]-labeling oxygen and nLC-MS/MS

Author(s)

Marques, Emerson Finco ; Medeiros, Marisa H. G. ; Di Mascio, Paolo ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Bioquim, Inst Quim, BR-05508000 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Journal of Mass Spectrometry; v. 52, n. 11, p. 739-751, NOV 2017.
• Web of Science Citations: 4

Abstract

Singlet molecular oxygen (O-1(2)) is generated in biological systems and reacts with different biomolecules. Proteins are a major target for O-1(2), and His, Tyr, Met, Cys, and Trp are oxidized at physiological pH. In the present study, the modification of lysozyme protein by O-1(2) was investigated using mass spectrometry approaches. The experimental findings showed methionine, histidine, and tryptophan oxidation. The experiments were achieved using {[}O-18]-labeled O-1(2) released from thermolabile endoperoxides in association with nano-scale liquid chromatography coupled to electrospray ionization mass spectrometry. The structural characterization by nLC-MS/MS of the amino acids in the tryptic peptides of the proteins showed addition of {[}O-18]-labeling atoms in different amino acids. (AU)

• FAPESP's process: 12/12663-1 - Singlet molecular oxygen and peroxides in chemical biology
• Grantee: Paolo Di Mascio
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/07937-8 - Redoxome - Redox Processes in Biomedicine
• Grantee: Ohara Augusto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC