Structure of a protein G helix variant suggests the importance of helix propensity and helix dipole interactions in protein design

Protein Sci. 2000 Jul;9(7):1391-4. doi: 10.1110/ps.9.7.1391.


Six helix surface positions of protein G (Gbeta1) were redesigned using a computational protein design algorithm, resulting in the five fold mutant Gbeta1m2. Gbeta1m2 is well folded with a circular dichroism spectrum nearly identical to that of Gbeta1, and a melting temperature of 91 degrees C, approximately 6 degrees C higher than that of Gbeta1. The crystal structure of Gbeta1m2 was solved to 2.0 A resolution by molecular replacement. The absence of hydrogen bond or salt bridge interactions between the designed residues in Gbeta1m2 suggests that the increased stability of Gbeta1m2 is due to increased helix propensity and more favorable helix dipole interactions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Algorithms
  • Crystallography, X-Ray
  • Hydrogen Bonding
  • Models, Molecular
  • Mutation
  • Nerve Tissue Proteins / chemistry*
  • Nerve Tissue Proteins / genetics
  • Protein Conformation
  • Protein Engineering / methods
  • Static Electricity


  • G-substrate
  • Nerve Tissue Proteins

Associated data

  • PDB/1EM7
  • PDB/1PGA