Question: what have you discovered in science?

Ailsa Powell answered on 20 Jun 2011:

The best result I have had so far in my career involved the protein that is the target of penicillin in bacteria. I solved the structure of the protein from a penicillin sensitive strain of bacteria and one from a penicililn resistant strain of the same type of bacteria. My aim was to see how the protein structure altered to prevent the penicilin binding but still alllow the natural substrate of the protein to bind. The results were quite surprising, there was hardly any visual difference at all!

Following more experiments that involved heating the proteins up to see at what point they unfolded I managed to work out that the difference between the penicillin sensitive protein and the penicillin resistant protein was stabilty. The penicillin resisitant protein was more unstable, meaning that it had a greated tendancy to unfold. In terms of binding penicillin over it’s natural substrate, it meant that it became more stable when binding the larger natural substrate and so could continue to perform it’s normal cellular role but it was too unstable to bind the much smaller penicillin molecule.

It was a good result and me and my boss were very happy 🙂