Institution: | 1. Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK;2. Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK;3. Department of Biochemistry & Molecular Biology, The University of Texas, McGovern Medical School, Houston, TX 77030, USA;4. Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK |