title: Competition between surface adsorption and folding of fibril-forming polypeptides.
abstract: Self-assembly of polypeptides into fibrillar structures can be initiated by planar surfaces that interact favorably with certain residues. Using a coarse-grained model, we systematically studied the folding and adsorption behavior of a β-roll forming polypeptide. We find that there are two different folding pathways depending on the temperature: (i) at low temperature, the polypeptide folds in solution into a β-roll before adsorbing onto the attractive surface; (ii) at higher temperature, the polypeptide first adsorbs in a disordered state and folds while on the surface. The folding temperature increases with increasing attraction as the folded β-roll is stabilized by the surface. Surprisingly, further increasing the attraction lowers the folding temperature again, as strong attraction also stabilizes the adsorbed disordered state, which competes with folding of the polypeptide. Our results suggest that to enhance the folding, one should use a weakly attractive surface. They also explain the recent experimental observation of the nonmonotonic effect of charge on the fibril formation on an oppositely charged surface [C. Charbonneau et al., ACS Nano 8, 2328 (2014)].
authors.affiliation: Van 't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.|Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Ran
authors.initials: R
authors.lastname: Ni
authors.affiliation: Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: J Mieke
authors.initials: JM
authors.lastname: Kleijn
authors.affiliation: Centre for Integrative Bioinformatics (IBIVU), Vrije Universiteit, De Boelelaan 1081A, 1081 HV Amsterdam, The Netherlands.
authors.forename: Sanne
authors.initials: S
authors.lastname: Abeln
authors.affiliation: Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Martien A
authors.initials: MA
authors.lastname: Cohen Stuart
authors.affiliation: Van 't Hoff Institute for Molecular Sciences, Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Bolhuis
mesh_terms: D000327:Adsorption; D003198:Computer Simulation; D008958:Models, Molecular; D009010:Monte Carlo Method; D010455:Peptides / Q000737:chemistry*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D012996:Solutions; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature
chemical_list: D010455:Peptides; D012996:Solutions; D012997:Solvents