A Designed Functional Metalloenzyme that Reduces O₂ to H₂O with Over One Thousand Turnovers

Abstract

Summary Rational design of functional enzymes with high turnovers is a significant challenge, especially those with complex active site and difficult reactions, such as in respiratory oxidases. Introducing 2 His and 1 Tyr into myoglobin resulted in designed enzymes that reduce O2 to H2O with > 1000 turnovers and minimal release of reactive oxygen species. This also showed that presence and positioning of Tyr, not Cu, are critical for activity.

Elementary tetrahelical protein design for diverse oxidoreductase functions

“…Distinctly different functions can be realized with minimal change, sometimes as small as one amino acid. The approach complements other protein design methods that have explored combinatorial 18,42-44 and computational 45-47 techniques and reengineering of natural proteins 48 , targeting single functions modeled on natural oxidoreductases.…”

Protein Design: Toward Functional Metalloenzymes

“…Miner et al introduced a Tyr residue at two different positions close to the copper-coordinating His of the Cu B site, aiming to examine whether this functionality would lead to higher efficiency in the reduction of oxygen to water. 485 IA Phe four residues away from the copper-coordinating His29 was substituted with a Tyr to mimic the native HCO, leading to F33Y-Cu B Mb. The second design was based on the crystal structure of a cbb 3 HCO, 486 and resulted in the G65Y-Cu B Mb mutant.…”

Coordination complexes and biomolecules: A wise wedding for catalysis upgrade

“…3, right panel (mutations L29H, F43H, and V68E) and the Fe(II) ions in red. Similarly, WTmyoglobin was implemented to coordinate Cu ion, thus displaying a 4-electrons dioxygen reductase activity [39].…”