Enzymes: a tribute to Malcolm Dixon.

Professor Malcolm Dixon’s eightieth birthday fell on 18 April 1979. On behalf of the Molecular Enzymology Group of the Biochemical Society, Dr. R. N. Perham organized a Colloquium in Cambridge on 6th April to celebrate the event. Many of Professor Dixon’s former colleagues and students attended this, and the excellent dinner at King’s College that followed. The speakers at the Colloquium were Fred Sanger, Ita Askonas, Vince Massey, Gregorio Weber, Keith Tipton and Dick Cammack. Malcolm Dixon’s career has been closely linked with Cambridge, and spans almost the whole period of British Biochemistry. He was born, in central Cambridge, in 1899 and attended the local, Perse, grammar school until the age of 12, when illness ended his school career. For the next 6 years, with informal teaching and much individual enterprise (covering subjects as diverse as music, natural history, ancient Egyptian and Hebrew languages and carpentry), he acquired enough education to sit and pass all the papers in the Cambridge University entrance examination, and entered Emmanuel College in the autumn of 19 17. Despite never having formally studied any science before, Malcolm Dixon intended to specialize in agricultural science, and in fact studied physics, chemistry and physiology for the Natural Sciences Trips. The University had appointed Gowland Hopkins as the first Professor of Biochemistry in 1914, but biochemistry did not become a full subject for teaching until 1924. Nevertheless, the physiology course contained a certain amount of biochemistry, and, after graduating in 1921, Malcolm Dixon was encouraged by Hopkins to remain in the young Biochemistry Department to study for a Ph.D. Degree. Until 1925, the Cambridge Biochemistry Department was housed, rather unsatisfactorily, in two separate buildings, and it was in both of these that Malcolm Dixon’s research and teaching careers began. On the teaching side, he became successively a Senior Demonstrator in 1923, a Lecturer in 1928, a Reader in 1945 and a Professor in 1966. On the research side, his first work was on glutathione and on xanthine oxidase, these introducing him to an abiding interest which might well be summarized in the title of his Ph.D. Thesis, submitted in 1925: ‘The types of oxidation-reduction systems, enzymic and non-enzymic, present in living animal systems’. It was in this field, which would now be called ‘bioenergetics’, that the first of Malcolm Dixon’s three influential books (‘Manometric Methods’, 1934) as well as many research papers, was published. Many of the co-authors of the papers are well known in the formative years of biochemistry and include J. H. Quastel, H. E. Tunnacliffe, S. Thurlow, D. Keilin, R. Hill, D. E. Green, R. Lemberg and L. F. Leloir. At that time Malcolm Dixon did not regard himself as an enzymologist, since J. B. S. Haldane taught that subject at Cambridge. But after Haldane’s departure in 1932, Malcolm Dixon took over his teaching, and lectured on enzymology at Cambridge for the succeeding 35 years. His research interests also diversifled somewhat, partly as a result of the Second World War, when he headed a Cambridge team working on the action of nerve gases on enzymes, and partly after the war when, in PROFESSOR MALCOLM DIXON, F.R.S.