Head
of the Biology and Medicine College
Protein Crystallography, Membrane
Proteins & Synchrotron Radiation
Research into Photosynthic
complexes from purple bactera and the process by which solar energy is
captured and transported. The structure of the B800-850 LH2 complex
showed the importance of pigmemt organisation in these complexes and
explained many of the observation on the efficiency of the energy
trapping and transfer process. We have recently extended the detail of
the structure to 2.0 Å resolution revealing features that were not
visible at lower resolution. We are expanding our work in this area to
include a novel low-light adapted B800 LH2 complex from Rps. palustris.
This has a number of imporant differences such as more
bacteriochlorophyll pigments per repeating unit, an octameric symmetry
and a specific peptide composition. The aim is to understand how this
novel LH2 complex confers an advatage to the organism in low-light
conditions. We are collaborating with Dr. T Aartsma at Leiden University
and are using single molecule spectroscopy and QM modeling methods to
give additional insight into the details of pigment energy states and
disorder. A proper understanding of energy transfer requires some
knowledge of energy disorder and dynamics. We are investigating motions
between pigment molecules with TLS refinement of the X-ray data and
normal mode analysis. (Click
here for more..)
The expression of diffirent LH2 complexes in Rps. palustris is under the
control of a number of bacterial phytochromes. These bacterial
phytochromes are believed to work in a similar way to the plant
phytochromes but use biliverdin for the light driven sensing of the
proportions of light in the red and far-red part of the spectrum. These
phytochromes are thought to directly interact with DNA bound
regulating proteins. We have over-expressed the main phytochrome
responsible for controling the whole cluster of photosynthetic complexes
and pigment synthesising enzymes.
We are investigating a number of murien cell wall synthesising enzymes
from M. tuberculosis in collabration with Colorado State University. Two
of these are integral membrane proteins MurX and FtsW. The membrane
protein FtsW is of interest as it is involved in the transport of a
peptidoglycan precursor molecule across the cell wall . This is achieved
by an attachment to a large cofactor molecule called Lipid II. FtsW is
important for cell wall formation during cell division or sporilation.
Understanding the structure of FtsW may help to develop drugs capable of
controlling the spread of the TB disease by intefering with M.
tuberculosis reproduction.
We are developing beamline hardware automation at the SRS in
conjunction with an e-science programme of software automation from the
stage of data collection to structure determination. This programme is
in collaboration with the OPPF (Oxford), CCP4, York, EBI, BM14 ESRF
and CIMR and will look at all aspects of automation from protein
production to structure deposition. GRID technology will be used to
link these centres together so that remote access to experiments and
data can be acheived. |
(44) 1925 603388
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