Noncovalent bonding

Overview

In general, noncovalent bonding refers to a variety of interactions that are not Van der Waals forces, i.e. "London dispersion forces", and Dipole-dipole bonds.

The terms "noncovalent bonding," "noncovalent interactions," and "noncovalent forces" all refer to these forces as a whole without specifying or distinguishing which specific forces are involved: noncovalent interactions often involve several of these forces working in concert. Noncovalent bonds are weak by nature and must therefore work together to have a significant effect. In addition, the combined bond strength is greater than the sum of the individual bonds. This is because the enthalpies of each bond due to entropic effects.

Examples

Protein structure

Main article: Protein structure

Intramolecular noncovalent interactions are largely responsible for the secondary and tertiary structure of proteins and therefore the protein's function in the mechanisms of life. Intermolecular noncovalent interactions are responsible for protein complexes (quaternary structure) where two or more proteins function in a coherent mechanism.

Pharmaceuticals

Most drugs work by noncovalently interacting with biomolecules such as covalent bonds with the biomolecules they interact with; instead, they interfere with or activate some biological mechanism through noncovalently interacting in very specific locations on specific biomolecules which present the perfect combination of noncovalent binding partners in just the right geometry.

See also

• Ionic bond
• Hydrophobic interactions
• Hydrogen bond
• Van der Waals force
• Intermolecular force

References

1. ^ Noncovalent bonding in Supramolecular Chemistry - Christoph A. Schalley
2. ^ ^{a b} Noncovalent bonds – Molecular Cell Biology (textbook), Lodish, Berk, Zipursky, Matsudaira, Baltimore, Darnell.
3. ^ Noncovalent bonding - Kimball's biology (textbook), 1995 ed.