Conformational Stabilization and Rapid Labeling of a 29-Residue Peptide by a Small Molecule Reaction Partner
Year: 2019
Type: article
Abstract: A 29-residue peptide (MP01), identified by in vitro selection for reactivity with a small molecule perfluoroaromatic, was modified and characterized using experimental and computational techniques, with the goal of understanding the molecular basis of its reactivity. These studies identified a six-amino acid point mutant (MP01-Gen4) that exhibited a reaction rate constant of 25.8 ± 1.8 M –1 s –1 at pH 7.4 and room temperature, approximately 2 orders of magnitude greater than that of its progenitor sequence and 3 orders of magnitude greater than background cysteine reactivity. MP01-Gen4 appeared to be conformationally dynamic and exhibited several properties reminiscent of larger protein molecules, including denaturant-sensitive structure and reactivity. We believe the majority of the reaction rate enhancement can be attributed to interaction of MP01-Gen4 with the perfluoroaromatic probe, which was found to stabilize a helical conformation of both MP01-Gen4 and nonreactive Cys-to-Ser or Cys-to-Ala variants. These findings demonstrate the ability of dynamic peptides to access proteinlike reaction mechanisms and the potential of perfluoroaromatic functionality to stabilize small peptide folds.
Source: Biochemistry
Institutions: Massachusetts Institute of Technology, Harvard University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
Funders: National Science Foundation, Massachusetts Institute of Technology, Massachusetts Green High Performance Computing Center, National Institutes of Health, Defense Advanced Research Projects Agency, National Institute of General Medical Sciences, National Institute of Biomedical Imaging and Bioengineering
OpenAlex ID: W2914987123