1MI0

Crystal Structure of the redesigned protein G variant NuG2

Summary for 1MI0

• Entry DOI: 10.2210/pdb1mi0/pdb
• Related: 1mhx
• Descriptor: immunoglobulin-binding protein G (2 entities in total)
• Functional Keywords: alpha-beta protein, redesigned beta-hairpin, immune system
• Biological source: Finegoldia magna
• Total number of polymer chains: 2
• Total formula weight: 14712.09

Authors

Nauli, S.,Kuhlman, B.,Le Trong, I.,Stenkamp, R.E.,Teller, D.C.,Baker, D. (deposition date: 2002-08-21, release date: 2002-09-18, Last modification date: 2024-02-14)

Primary citation

Nauli, S.,Kuhlman, B.,Le Trong, I.,Stenkamp, R.E.,Teller, D.C.,Baker, D.
Crystal structures and increased stabilization of the protein G variants with switched folding pathways NuG1 and NuG2
Biochemistry, 11:2924-2931, 2002

PubMed Abstract: We recently described two protein G variants (NuG1 and NuG2) with redesigned first hairpins that were almost twice as stable, folded 100-fold faster, and had a switched folding mechanism relative to the wild-type protein. To test the structural accuracy of our design algorithm and to provide insights to the dramatic changes in the kinetics and thermodynamics of folding, we have now determined the crystal structures of NuG1 and NuG2 to 1.8 A and 1.85 A, respectively. We find that they adopt hairpin structures that are closer to the computational models than to wild-type protein G; the RMSD of the NuG1 hairpin to the design model and the wild-type structure are 1.7 A and 5.1 A, respectively. The crystallographic B factor in the redesigned first hairpin of NuG1 is systematically higher than the second hairpin, suggesting that the redesigned region is somewhat less rigid. A second round of structure-based design yielded new variants of NuG1 and NuG2, which are further stabilized by 0.5 kcal/mole and 0.9 kcal/mole.

PubMed: 12441390
DOI: 10.1110/ps.0216902

Experimental method

X-RAY DIFFRACTION (1.85 Å)