Accolade for Neil Ball of University of Portsmouth
The SCI BioActive Science Group prize for the best final year project in molecular aspects of biology at the University of Portsmouth was awarded in 2007 to Neil Ball for his project entitled 'Limited proteolysis as a probe of HsdR domain structure', and supervised by Dr Keith Firman.
In this work Neil aimed to determine the location of particular regions of the bacterial protein HsdR. This is an important protein that allows the bacteria to destroy non-self DNA, thus acting like an immune system. It is known to consist of at least three regions (domains) each of which performs a specific function i) binding to a core protein complex on the foreign DNA, ii) translocating ('pulling') the DNA and iii) cutting the DNA.
The project involved producing and subsequently purifying the protein on the basis of charge, using ion exchange and affinity chromatography, and then cutting the protein into discrete pieces using proteolytic enzymes. The fragments were then separated by electrophoresis on the basis of size. The cutting process was carried out over a period of 90 minutes, and samples taken with elapsed time. The appearance of new fragments with time allowed the positions of the various domains to be identified by comparing putative domains with other domains from similar proteins in a database. It was then possible for the domains to be mapped to the protein sequence.
This technique is known as limited proteolysis, and produces very low resolution maps of a protein. However, it has not been possible to determine the structure by using higher resolution techniques, such as crystallography and NMR, because of the large size and flexibility of the protein.
Since the award of his first degree Neil has gone on to join the research group of Professor Geoff Kneale in the Structural Biology Laboratories of the School of Biological Sciences at Portsmouth. He is undertaking postgraduate research training, and his PhD topic is 'The biochemical and biophysical analysis of protein/DNA interactions in bacterial controller protein'.
Richard Greenwood adds, 'We are grateful to SCI for providing the prize since it allows us to recognise and reward excellent work. I will encourage Neil to take an active part in SCI. We are always looking for good postgraduate students to join the committees.'