When I look back over more than 40 years of research and more than 400 papers, the investigation that always comes to mind first is one I carried out with Rod Gregory in 1946, very early in our careers.
Working together in a shabby basement laboratory in Liverpool, we demonstrated that in mammals vitamin A is formed from beta-carotene as it crosses the intestinal wall. Today, this may seem an elementary observation. Yet it gave us a tremendous thrill, and was important because it overturned the dogma of the day—that the transformation occurred in the liver.
The event was significant for me too because its original inspiration was a lecture I had attended as an undergraduate eight years earlier. Although interested in biochemistry even when at school, I had opted to study “straight” chemistry at Liverpool University because a condition of my bursary was that I should take up teaching ...
