Singlet oxygen-induced protein aggregation: Lysozyme crosslink formation and nLC-MS/MS characterization

Author(s)

Marques, Emerson Finco ^{[1, 2]} ; Medeiros, Marisa H. G. ^[1] ; Di Mascio, Paolo ^[1]

Affiliation

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

^[2] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Sao Paulo - Brazil

• Document type: Journal article
• Source: Journal of Mass Spectrometry; v. 54, n. 11, p. 894-905, NOV 2019.
• Web of Science Citations: 0

Abstract

Singlet molecular oxygen (O-1(2)) has been associated with a number of physiological processes. Despite the recognized importance of O-1(2)-mediated protein modifications, little is known about the role of this oxidant in crosslink formation and protein aggregation. Thus, using lysozyme as a model, the present study sought to investigate the involvement of O-1(2) in crosslink formation. Lysozyme was photochemically oxidized in the presence of rose bengal or chemically oxidized using {[}O-18]-labeled O-1(2) released from thermolabile endoperoxides. It was concluded that both O-1(2) generating systems induce lysozyme crosslinking and aggregation. Using SDS-PAGE and nano-scale liquid chromatography coupled to electrospray ionization mass spectrometry, the results clearly demonstrated that O-1(2) is directly involved in the formation of covalent crosslinks involving the amino acids histidine, lysine, and tryptophan. (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