Related Experiment Video
Updated: Aug 8, 2026

From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
Published on: July 4, 2016
Alternate routes to conformational specificity in a Greek key beta barrel protein
1Division of Molecular and Structural Biology, Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, Ontario, Canada.
Abstract:
The N-terminal domain of protein S, a Greek key calcium-binding protein from Myxococcus xanthus, forms an atypical molten globule in the calcium-free state. The structure of this state is characterized by significant conformational fluctuations, which are localized to a subdomain that is not contiguous along the polypeptide chain. The conformational instability of this subdomain appears to arise from repulsive electrostatic interactions of four acidic side chains that are clustered together but are removed from the calcium-binding sites. This domain can be induced to form a native-like state through two different routes, calcium binding or reduction of pH. Acid-induced folding stabilizes the locally unfolded subdomain by selectively removing repulsive interactions without significantly affecting global stability. In contrast, calcium binding appears to increase local stability indirectly by causing global stabilization.
More Related Videos
Related Concept Videos
Protein Organization
Protein Folding
Conserved Binding Sites
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Protein Organization
The primary structure of a protein is its amino acid sequence.
Protein Folding
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Multi-pass Transmembrane Proteins and β-barrels
α-Helix containing multi-pass transmembrane proteins
Multi-pass transmembrane proteins such as G-protein-linked receptors (GPCRs) and...

