International collaboration in chemistry: mechanism of operation of the BLUF domain - blue light sensitive biosensors

Plants and animals respond to light - the growth of a plant toward sunlight is an example (our own 'body clock' may be another). In this project we investigate the mode of operation of one recently discovered blue light sensitive protein, which controls the expression of bacterial photosynthesis. This study requires complementary skills in protein chemistry, spectroscopy and dynamics, which are a particular feature of the research team. What is known about the light sensing mechanism is that blue light absorbed by a flavin produces a structural change in the protein. What is not known is how and how fast. Our first objective will be to use the structural and dynamic information available from ultrafast electronic and vibrational spectroscopy to address these questions in the native protein. To do this we will use a traditional tool of spectroscopy - but one which is difficult to apply to proteins - isotope substitution. Having characterised the mechanism we will then seek to modify and enhance it through chemical manipulation of the protein structure. This research addresses the fundamental mechanism of operation of the light sensitive protein, but our long term aim is to regulate and enhance the blue light response to develop photoactive proteins, which might, for example, be used for light activated drug release.