5NPO

Promiscuous Protein Self-Assembly as a Function of Protein Stability

Summary for 5NPO

• Entry DOI: 10.2210/pdb5npo/pdb
• Descriptor: Beta-lactamase TEM, Beta-lactamase, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: tem1 beta-lactamase hetrodimer, hydrolase
• Biological source: Escherichia coli; More
• Total number of polymer chains: 2
• Total formula weight: 58066.67

Authors

Cohen-Khait, R.,Dym, O.,Hamer-Rogotner, S.,Schreiber, G. (deposition date: 2017-04-18, release date: 2017-12-20, Last modification date: 2024-10-23)

Primary citation

Cohen-Khait, R.,Dym, O.,Hamer-Rogotner, S.,Schreiber, G.
Promiscuous Protein Binding as a Function of Protein Stability.
Structure, 25:1867-1874.e3, 2017

PubMed Abstract: Proteins have evolved to balance efficient binding of desired partners with rejection of unwanted interactions. To investigate the evolution of protein-protein interactions, we selected a random library of pre-stabilized TEM1 β-lactamase against wild-type TEM1 using yeast surface display. Three mutations were sufficient to achieve micromolar affinity binding between the two. The X-ray structure emphasized that the main contribution of the selected mutations was to modify the protein fold, specifically removing the N'-terminal helix, which consequently allowed protein coupling via a β-sheet-mediated interaction resembling amyloid interaction mode. The only selected mutation located at the interaction interface (E58V) is reminiscent of the single mutation commonly causing sickle-cell anemia. Interestingly, the evolved mutations cannot be inserted into the wild-type protein due to reduced thermal stability of the resulting mutant protein. These results reveal a simple mechanism by which undesirable binding is purged by loss of thermal stability.

PubMed: 29211984
DOI: 10.1016/j.str.2017.11.002

Experimental method

X-RAY DIFFRACTION (1.95 Å)