GA-79-MBP cs-rosetta structures

Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 3000 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation   3D Report Full Report

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Subdomain interactions foster the design of two protein pairs with 80% sequence identity but different folds.

Porter, L.L.He, Y.Chen, Y.Orban, J.Bryan, P.N.

(2015) Biophys J 108: 154-162

  • DOI: https://doi.org/10.1016/j.bpj.2014.10.073
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Metamorphic proteins, including proteins with high levels of sequence identity but different folds, are exceptions to the long-standing rule-of-thumb that proteins with as little as 30% sequence identity adopt the same fold. Which topologies can be bridged by these highly identical sequences remains an open question. Here we bridge two 3-α-helix bundle proteins with two radically different folds. Using a straightforward approach, we engineered the sequences of one subdomain within maltose binding protein (MBP, α/β/α-sandwich) and another within outer surface protein A (OspA, β-sheet) to have high sequence identity (80 and 77%, respectively) with engineered variants of protein G (GA, 3-α-helix bundle). Circular dichroism and nuclear magnetic resonance spectra of all engineered variants demonstrate that they maintain their native conformations despite substantial sequence modification. Furthermore, the MBP variant (80% identical to GA) remained active. Thermodynamic analysis of numerous GA and MBP variants suggests that the key to our approach involved stabilizing the modified MBP and OspA subdomains via external interactions with neighboring substructures, indicating that subdomain interactions can stabilize alternative folds over a broad range of sequence variation. These findings suggest that it is possible to bridge one fold with many other topologies, which has implications for protein folding, evolution, and misfolding diseases.

  • Organizational Affiliation

    Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland; Potomac Affinity Proteins, Rockville, Maryland. Electronic address: llporter@umd.edu.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
GA-79-MBP, maltose binding protein56Streptococcus dysgalactiaeMutation(s): 0 
Find proteins for A0A0J9X1W7 (Streptococcus dysgalactiae)
Explore A0A0J9X1W7 
Go to UniProtKB:  A0A0J9X1W7
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA0A0J9X1W7
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 3000 
  • Conformers Submitted: 10 
  • Selection Criteria: structures with the lowest energy 

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-04-08
    Type: Initial release
  • Version 1.1: 2024-05-01
    Changes: Data collection, Database references