[Q] What was it, Dorothy, that you were looking for in the insulin structure?

Just what it was, you know, how the peptide chain... of course it was a very important step for us when [Fred] Sanger found the sequence. We didn't in any sense need to know it for our analysis, but it cheered us up like anything to see our distribution of atoms conforming to that expected from Sanger's sequence.

[Q] Now, when the structure came out in 1969, you, I remember very well, Dorothy, and others of us spent two days, I think, interpreting that map, and when the structure was complete we had the details really of a heximer, which I don't know what you thought about at the time, Dorothy, but it was, I think, a very beautiful structure.

Yes.

[Q] And it... in a sense, one of the first things we did was to think about Svedberg's experiments which were telling us that we had different conditions, heximers and dimers. And do you remember... can you remember looking inside this heximer for the fundamental dimer?

Yes. I'm also sort of thinking of the fact that in the... our first letters to Nature I wrote about those early measurements. I measured, of course, the molecular weight of the rhombahedral unit cell and this contained six insulin one molecules and had a molecular weight of about 36 thousand. The first suggestion was that the insulin molecule might have a weight of 36 thousand, and this led to a very irate letter from Freudenberg who was a major chemical worker on insulin at the time, saying insulin was much smaller then this, it's at least not more than 11 thousand and maybe even less, and Svedberg only measures a particle weight in his measurements in the ultra centrifuge and this was all absolutely correct and proved by the final structure analysis.

I replied politely to Freudenberg I think at the time, but I didn't see Freudenberg until really very late when I was elected a member of Leopoldina which was an academy, a very old scientific academy. It's older than the Royal Society and it was essentially an academy for all German-speaking peoples and the... to my surprise when I went to the first meeting, and I went to the Leopoldina I found that it was... there were present East and West Germans and they got away with going on meeting together in the Leopoldina all the way through this episode of the partition of Germany, and the first person I met on the steps of the Leopoldina as I was going in was Freudenberg himself and I had the structure of insulin in my hand.