Credit: © 2007 ACS

Proteins often fold in confined spaces, such as virus capsids or pores. Experiments and theoretical studies both show that proteins tend to be more stable and less likely to denature when they are constrained in small volumes. Understanding how the shape of such a nanocontainer influences protein folding would provide an additional way to control biomaterials.

Shao-Qing Zhang and Margaret Cheung at the University of Houston in the US have therefore developed a systematic strategy to explore how the geometry of a nanocontainer affects the dynamics of biopolymers1. They used molecular simulations to investigate changes in the shape of a particular protein (the B1 domain of Streptococcal G) over time when it is confined in a spherical, ellipsoidal or pancake-like container that is a few nanometres in size. The calculations show that the flat pancake-like containers lead to the greatest enhancement in the rate of protein folding. It is suggested that this particular shape most closely follows the intermediate configuration of the proteins as they transition from unfolded to their most favourable folded state.

The team believes that these studies will lead to drugs that are expressly designed to manipulate how proteins bind with one another or fold and configure in cells, with wide applications in nanobiotechnology.