Introductory remarks to the third session
This session is of particular personal interest to me. Almost exactly four years ago I completed the manuscript of my book with a section on glycolytic enzymes. At that time, some very interesting and tantalizing results were emerging from the crystallographic laboratories in Bristol and Oxford, so I paid visits to Dr Watson and Dr Muirhead and Professor Phillips with the result that I was able to include some speculative, unpublished, ideas on mechanism. It is now most intriguing to see the progress since 1976 and how some early speculations have held up or developed. The first speakers in this session, Dr Watson and Dr Fothergill, had just found a most striking feature at the active site of phosphoglycerate mutase: the two imidazole rings of the active site histidines are parallel and only 4 A apart, apparently well set up for shuffling the phosphate between 2-phosphoglycerate and 3-phosphoglycerate via two phosphoenzyme intermediates. I see from the abstract that subsequent data conflict with this idea.