Shining light with synthetic biology
11 September 2012
Molecular structure of a new energy transfer protein scaffold comprised of a "light harvesting" (green) and an "energy accepting" (red) component.
School of Biosciences Senior Lecturer Dr Dafydd Jones has led a collaborative research program that has significantly enhanced one aspect of the field of synthetic biology. Synthetic biology attempts to apply engineering design and principles to construct new biological parts, devices, and systems.
Recently published (http://pubs.acs.org/doi/abs/10.1021/ja301987h) in the Journal of the American Chemical Society, Dr Jones' group have constructed new and potentially useful protein components that are not normally present in nature. In doing so, the team have demonstrated some of the molecular principles which can be used to design new proteins with dual, yet linked, functions.
James Arpino, a BBSRC CASE PhD student from the Jones group, took two normally unrelated proteins and linked their individual functions. The two proteins were a "light harvesting" fluorescent protein and an "energy accepting" cytochrome protein. When combined the resulting new protein scaffold was able to absorb and transmit light energy with very high efficiency – akin to an artificial mini version of the light capturing machines used in photosynthesis.
To learn more about how this brand new protein achieves its new functions, the atomic level 3D structure was determined in collaboration with Matthias Bochtler during his time at the School of Biosciences. The structure revealed an unexpected arrangement of the individual proteins which perfectly explains how the functions were coupled: the two active centres of the constitutive parts were placed close to each other in space. The work represents the first structure of proteins constructed in this manner and provides an insight into the molecular principles by which new proteins with coupled functions can be designed.
Dr Jones explains “We have shown that proteins truly are plastic in nature and we can mould them through engineering to have functions and structures not normally envisaged and unrestricted by what already exists in nature. This is of major significance in synthetic biology. Our detailed structural analysis of this new protein is the first of its kind for this type so has provided vital new information on how to construct future proteins with novel properties”.