6X7E

Co-bound structure of an engineered protein trimer, TriCyt3, with delta isomerism at the hexahistidine coordination site

Summary for 6X7E

• Entry DOI: 10.2210/pdb6x7e/pdb
• Descriptor: Soluble cytochrome b562, HEME C, COBALT (II) ION, ... (6 entities in total)
• Functional Keywords: four-helix bundle, metalloprotein trimer, metal binding protein
• Biological source: Escherichia coli
• Total number of polymer chains: 3
• Total formula weight: 37520.40

Authors

Tezcan, F.A.,Kakkis, A. (deposition date: 2020-05-29, release date: 2020-09-16, Last modification date: 2024-10-23)

Primary citation

Kakkis, A.,Gagnon, D.,Esselborn, J.,Britt, R.D.,Tezcan, F.A.
Metal-Templated Design of Chemically Switchable Protein Assemblies with High-Affinity Coordination Sites.
Angew.Chem.Int.Ed.Engl., 59:21940-21944, 2020

PubMed Abstract: To mimic a hypothetical pathway for protein evolution, we previously tailored a monomeric protein (cyt cb ) for metal-mediated self-assembly, followed by re-design of the resulting oligomers for enhanced stability and metal-based functions. We show that a single hydrophobic mutation on the cyt cb surface drastically alters the outcome of metal-directed oligomerization to yield a new trimeric architecture, (TriCyt1) This nascent trimer was redesigned into second and third-generation variants (TriCyt2) and (TriCyt3) with increased structural stability and preorganization for metal coordination. The three TriCyt variants combined furnish a unique platform to 1) provide tunable coupling between protein quaternary structure and metal coordination, 2) enable the construction of metal/pH-switchable protein oligomerization motifs, and 3) generate a robust metal coordination site that can coordinate all mid-to-late first-row transition-metal ions with high affinity.

PubMed: 32830423
DOI: 10.1002/anie.202009226

Experimental method

X-RAY DIFFRACTION (1.9987 Å)