Multiplex Chemical Labeling of Amino Acids for Protein Footprinting Structure Assessment.
Anal Chem
; 94(27): 9819-9825, 2022 07 12.
Article
em En
| MEDLINE
| ID: mdl-35763792
ABSTRACT
Protein footprinting with mass spectrometry is an established structural biology technique for mapping solvent accessibility and assessing molecular-level interactions of proteins. In hydroxyl radical protein footprinting (HRPF), hydroxyl (OH) radicals generated by water radiolysis or other methods covalently label protein side chains. Because of the wide dynamic range of OH reactivity, not all side chains are easily detected in a single experiment. Novel reagent development and the use of radical chain reactions for labeling, including trifluoromethyl radicals, is a potential approach to normalize the labeling across a diverse set of residues. HRPF in the presence of a trifluoromethylation reagent under the right conditions could provide a "one-pot" reaction for multiplex labeling of protein side chains. Toward this goal, we have systematically evaluated amino acid labeling with the recently investigated Langlois' reagent (LR) activated by X-ray-mediated water radiolysis, followed by three different mass spectrometry methods. We compared the reactivity of CF3 and OH radical labeling for all 20 protein side chains in a competition-free environment. We found that all 20 amino acids exhibited CF3 or OH labeling in LR. Our investigations provide the evidence and knowledge set to perfect hydroxyl radical-activated trifluoromethyl chemistry as "one-pot" reaction for multiplex labeling of protein side chains to achieve higher resolution in HRPF.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pegadas de Proteínas
/
Aminoácidos
Idioma:
En
Revista:
Anal Chem
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Estados Unidos