Identification of Cross-Linked Peptides by High-Resolution Precursor Ion Scan

Autor(es)

Iglesias, Amadeu H. ^[1] ; Santos, Luiz Fernando A. ^[1] ; Gozzo, Fabio C. ^[2]

Afiliação do(s) autor(es)

^[1] Inst Nacl Ciencia & Tecnol Bioanalit, BR-13083970 Campinas, SP - Brazil

^[2] Univ Estadual Campinas, Inst Chem, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Analytical Chemistry; v. 82, n. 3, p. 909-916, FEB 1 2010.
• Citações Web of Science: 22

Resumo

Chemical cross-linking coupled to mass spectrometry analysis has become a realistic alternative to the study of proteins structure and interactions, especially when these systems are not amenable to high-resolution techniques such as protein crystallography or nuclear magnetic resonance. One of the main bottlenecks of this approach relies on the detection of cross-linked peptides, as they are usually present in substoichiometric amounts in complex samples. It was shown that one of the main fragmentation pathways of disuccinimidyl suberate (DSS) cross-linked peptides yields diagnostic ions, whose structure is composed of a rearranged lysine side chain and the spacer arm of the linker. In this report, we demonstrate the feasibility of detecting these modified peptides based on a precursor ion scan in a quadrupole time-of-flight (Q-TOF) instrument. It was shown that the fragmentation of nonmodified tryptic peptides hardly generates ions with the same nominal mass of the diagnostic ions, making the precursor ion scan very specific to N-hydroxysuccinimide (NHS)-based cross-linkers. Moreover, the experimental setup is the same as in the case of a regular cross-linking experiment, not demanding any additional experimental steps that would increase sample handling. The results obtained with protein samples allowed us to propose an algorithm that could be implemented in a software to process data from cross-linking experiments in an automated and high-throughput way. (AU)

• Processo FAPESP: 07/55930-1 - Desenvolvimento de compostos quinazolínicos inibidores de adenosina quinase para uso terapêutico
• Beneficiário: Kleber Gomes Franchini
• Linha de fomento: Auxílio à Pesquisa - Parceria para Inovação Tecnológica - PITE
• Processo FAPESP: 08/57805-2 - Instituto de Bioanalítica
• Beneficiário: Lauro Tatsuo Kubota
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 04/14846-0 - Rede de proteoma do estado de São Paulo
• Beneficiário: Fabio Cesar Gozzo
• Linha de fomento: Auxílio à Pesquisa - Programa GENOMA