title: Crowning proteins: modulating the protein surface properties using crown ethers.
abstract: Crown ethers are small, cyclic polyethers that have found wide-spread use in phase-transfer catalysis and, to a certain degree, in protein chemistry. Crown ethers readily bind metallic and organic cations, including positively charged amino acid side chains. We elucidated the crystal structures of several protein-crown ether co-crystals grown in the presence of 18-crown-6. We then employed biophysical methods and molecular dynamics simulations to compare these complexes with the corresponding apoproteins and with similar complexes with ring-shaped low-molecular-weight polyethylene glycols. Our studies show that crown ethers can modify protein surface behavior dramatically by stabilizing either intra- or intermolecular interactions. Consequently, we propose that crown ethers can be used to modulate a wide variety of protein surface behaviors, such as oligomerization, domain-domain interactions, stabilization in organic solvents, and crystallization.
authors.affiliation: Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529 (Taiwan); Core Facilities for Protein Structural Analysis, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei 11529 (Taiwan).
authors.forename: Cheng-Chung
authors.initials: CC
authors.lastname: Lee
authors.forename: Manuel
authors.initials: M
authors.lastname: Maestre-Reyna
authors.forename: Kai-Cheng
authors.initials: KC
authors.lastname: Hsu
authors.forename: Hao-Ching
authors.initials: HC
authors.lastname: Wang
authors.forename: Chia-I
authors.initials: CI
authors.lastname: Liu
authors.forename: Wen-Yih
authors.initials: WY
authors.lastname: Jeng
authors.forename: Li-Ling
authors.initials: LL
authors.lastname: Lin
authors.forename: Richard
authors.initials: R
authors.lastname: Wood
authors.forename: Chia-Cheng
authors.initials: CC
authors.lastname: Chou
authors.forename: Jinn-Moon
authors.initials: JM
authors.lastname: Yang
authors.forename: Andrew H-J
authors.initials: AH
authors.lastname: Wang
mesh_terms: D004988:Ethers, Cyclic / Q000737:chemistry*; D008953:Models, Anatomic; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D015202:Protein Engineering; D013499:Surface Properties
chemical_list: D004988:Ethers, Cyclic
keywords: crown compounds; crystal growth; molecular dynamics; protein engineering; protein surfaces