title: Force-clamp spectroscopy detects residue co-evolution in enzyme catalysis.
abstract: Understanding how the catalytic mechanisms of enzymes are optimized through evolution remains a major challenge in molecular biology. The concept of co-evolution implicates that compensatory mutations occur to preserve the structure and function of proteins. We have combined statistical analysis of protein sequences with the sensitivity of single molecule force-clamp spectroscopy to probe how catalysis is affected by structurally distant correlated mutations in Escherichia coli thioredoxin. Our findings show that evolutionary anti-correlated mutations have an inhibitory effect on enzyme catalysis, whereas positively correlated mutations rescue the catalytic activity. We interpret these results in terms of an evolutionary tuning of both the enzyme-substrate binding process and the chemistry of the active site. Our results constitute a direct observation of distant residue co-evolution in enzyme catalysis.
authors.affiliation: Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
authors.forename: Raul
authors.initials: R
authors.lastname: Perez-Jimenez
authors.forename: Arun P
authors.initials: AP
authors.lastname: Wiita
authors.forename: David
authors.initials: D
authors.lastname: Rodriguez-Larrea
authors.forename: Pallav
authors.initials: P
authors.lastname: Kosuri
authors.forename: Jose A
authors.initials: JA
authors.lastname: Gavira
authors.forename: Jose M
authors.initials: JM
authors.lastname: Sanchez-Ruiz
authors.forename: Julio M
authors.initials: JM
authors.lastname: Fernandez
mesh_terms: D002384:Catalysis; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D008956:Models, Chemical; D013057:Spectrum Analysis; D013329:Structure-Activity Relationship; D013879:Thioredoxins / Q000737:chemistry*
chemical_list: D029968:Escherichia coli Proteins; D013879:Thioredoxins