1mj0
From Proteopedia
|
SANK E3_5: an artificial Ankyrin repeat protein
Overview
Ankyrin repeat (AR) proteins mediate innumerable protein-protein, interactions in virtually all phyla. This finding suggested the use of AR, proteins as designed binding molecules. Based on sequence and structural, analyses, we designed a consensus AR with fixed framework and randomized, interacting residues. We generated several combinatorial libraries of AR, proteins consisting of defined numbers of this repeat. Randomly chosen, library members are expressed in soluble form in the cytoplasm of, Escherichia coli constituting up to 30% of total cellular protein and show, high thermodynamic stability. We determined the crystal structure of one, of those library members to 2.0-A resolution, providing insight into the, consensus AR fold. Besides the highly complementary hydrophobic, repeat-repeat interfaces and the absence of structural irregularities in, the consensus AR protein, the regular and extended hydrogen bond networks, in the beta-turn and loop regions are noteworthy. Furthermore, all, residues found in the turn region of the Ramachandran plot are glycines., Many of these features also occur in natural AR proteins, but not in this, rigorous and standardized fashion. We conclude that the AR domain fold is, an intrinsically very stable and well-expressed scaffold, able to display, randomized interacting residues. This scaffold represents an excellent, basis for the design of novel binding molecules.
About this Structure
1MJ0 is a Single protein structure of sequence from Designed synthetic gene with SO4 and TRS as ligands. Full crystallographic information is available from OCA.
Reference
Designed to be stable: crystal structure of a consensus ankyrin repeat protein., Kohl A, Binz HK, Forrer P, Stumpp MT, Pluckthun A, Grutter MG, Proc Natl Acad Sci U S A. 2003 Feb 18;100(4):1700-5. Epub 2003 Feb 3. PMID:12566564
Page seeded by OCA on Sun Nov 25 04:15:12 2007
