Conversion of monomeric protein L to an obligate dimer by computational protein design.
Protein L consists of a single alpha-helix packed on a four-stranded beta-sheet formed by two symmetrically opposed beta-hairpins. We use a computer-based protein design procedure to stabilize a domain-swapped dimer of protein L in which the second beta-turn straightens and the C-terminal strand inserts into the beta-sheet of the partner. The designed obligate dimer contains three mutations (A52V, N53P, and G55A) and has a dissociation constant of approximately 700 pM, which is comparable to the dissociation constant of many naturally occurring protein dimers. The structure of the dimer has been determined by x-ray crystallography and is close to the in silico model.
Kuhlman
B
B
Department of Biochemistry and Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195, USA.
O'Neill
J W
JW
Kim
D E
DE
Zhang
K Y
KY
Baker
D
D
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics; D019281:Dimerization; D019791:Guanidine; D008958:Models, Molecular; D016296:Mutagenesis; D011489:Protein Denaturation; D017433:Protein Structure, Secondary
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C116593:L-protein, Peptococcus magnus; D019791:Guanidine