Metal-Templated Design of Chemically Switchable Protein Assemblies with High-Affinity Coordination Sites.Tezcan, F.A., Kakkis, A., Gagnon, D., Esselborn, J., Britt, R.D.
(2020) Angew Chem Int Ed Engl
- PubMed: 32830423
- DOI: 10.1002/anie.202009226
- Primary Citation of Related Structures:
6X7E, 6X8X, 6WZ2, 6WZ1, 6WZ3, 6WYU, 6WZ7, 6WZ0, 6WZA, 6WZC
- PubMed Abstract:
To mimic a hypothetical pathway ...
To mimic a hypothetical pathway for protein evolution, we previously developed a design strategy (Metal-Templated Interface Redesign), in which a monomeric protein (cytochrome cb562) was tailored for metal-mediated self-assembly, followed by the re-design of the resulting oligomers for enhanced stability and metal-based functions. Here we show that a single hydrophobic mutation on the cytochrome cb562 surface can drastically alter the outcome of metal-directed oligomerization to yield a new trimeric architecture, (TriCyt1)3, featuring an unusual hexa-histidine coordination motif. Through computational and rational redesign, this nascent trimer is converted into second and third-generation variants (TriCyt2)3 and (TriCyt3)3 with increased structural stability and preorganization for metal coordination. The three TriCyt variants combined furnish a unique design platform to a) provide tunable coupling between protein quaternary structure and metal coordination, b) enable the construction of metal/pH-switchable protein oligomerization motifs, and c) generate a robust metal coordination site that can accommodate all mid-to-late first-row transition metal ions with high affinity, including Mn(II) with nanomolar dissociation constants, rivaling those of the strongest Mn(II)-binding protein, calprotectin.
University of California Davis, Chemistry, UNITED STATES.