Frederick Sanger: One doesn’t think about Nobel Prizes all that much when you’re working at the bench. You’re interested in what you can do. I mean I was excited that I could get the peptide, and I extended that a bit, and I got some more sequences at the ends of the chains, and I think the main consequence of it was that then I realized that, you know, it was possible to do more sequencing and to do — and with other colleagues, we actually completed the complete sequence of the insulin, which — I mean it took quite a lot of time, but it did put me on the road and really decided my future work, and you know, all my work, all the work that’s really paid off, has been on sequencing, initially the proteins.

It’s really mostly involved in finding methods, really, finding out how to do it, and it does depend very much on other work in other labs. I mean in the case of these end groups, it depended very much on the work of Archie Martin, who was a rather brilliant physical chemist, and he invented a method of fractionation — I think I’ve already mentioned it, this partitioned chromatography, and then, later on, he developed another method, a two-dimensional paper chromatography, where you can just put your stuff on a sheet of filter paper and run solvent through the paper and you separate all the small fragments, the peptide, little bits on the paper, and we did a lot of this and cutting out the spots, seeing what amino acids they contained. So, you got little fragments, and then you had to work out how they could be fitted together, a jigsaw puzzle sort of a thing, sort of a jigsaw puzzle approach, fitting little bits together, and that was essentially the method that was used for protein sequence analysis.