The ability of bacteria to adhere to other cells or to surfaces depends on long, thin adhesive structures that are anchored to their cell walls. These structures include extended protein oligomers known as pili and single, multi-domain polypeptides, mostly based on multiple tandem Ig-like domains. Recent structural studies have revealed the widespread presence of covalent cross-links, not previously seen within proteins, which stabilize these domains. The cross-links discovered so far are either isopeptide bonds that link lysine side chains to the side chains of asparagine or aspartic acid residues or ester bonds between threonine and glutamine side chains. These bonds appear to be formed by spontaneous intramolecular reactions as the proteins fold and are strategically placed so as to impart considerable mechanical strength.
- cell-surface adhesins
- ester bond cross-links
- isopeptide bond cross-links
- Ig-like domains
- mechanical strength
- self-generated covalent bonds
Repetitive, Non-Globular Proteins: Nature to Nanotechnology: Held at the University of York, U.K., 30 March 2015–1 April 2015.
- mass spectrometry;
- quantum mechanics/molecular mechanics
- © 2015 Authors; published by Portland Press Limited