title: A de novo designed protein protein interface.
abstract: As an approach to both explore the physical/chemical parameters that drive molecular self-assembly and to generate novel protein oligomers, we have developed a procedure to generate protein dimers from monomeric proteins using computational protein docking and amino acid sequence design. A fast Fourier transform-based docking algorithm was used to generate a model for a dimeric version of the 56-amino-acid beta1 domain of streptococcal protein G. Computational amino acid sequence design of 24 residues at the dimer interface resulted in a heterodimer comprised of 12-fold and eightfold variants of the wild-type protein. The designed proteins were expressed, purified, and characterized using analytical ultracentrifugation and heteronuclear NMR techniques. Although the measured dissociation constant was modest ( approximately 300 microM), 2D-[(1)H,(15)N]-HSQC NMR spectra of one of the designed proteins in the absence and presence of its binding partner showed clear evidence of specific dimer formation.
authors.affiliation: Howard Hughes Medical Institute and Division of Biology, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: Po-Ssu
authors.initials: PS
authors.lastname: Huang
authors.forename: John J
authors.initials: JJ
authors.lastname: Love
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Mayo
mesh_terms: D000465:Algorithms; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D019295:Computational Biology; D003198:Computer Simulation; D019281:Dimerization; D005583:Fourier Analysis; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D015202:Protein Engineering; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary
chemical_list: D001426:Bacterial Proteins; C034284:IgG Fc-binding protein, Streptococcus