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You started with the enzyme subtilisin, which breaks down milk protein, and used directed evolution to produce a version of it that worked not in a water-based solution but in an organic solvent.

Despite Seidah's protests, the journal editors gave both the gene and its protein product a new name that fit with standard nomenclature: proprotein convertase subtilisin/kexin type 9, or PCSK9.

PCSK9 — which stands for proprotein convertase subtilisin/kexin type 9 — also binds to the LDL receptor, and when it does so, the receptor is destroyed along with the LDL.

The group's latest interest has been an enzyme called subtilisin, which is found in ordinary soil bacteria.

As they investigated subtilisin's complex structure, the scientists realized that it had a curious similarity to another enzyme, chymotrypsin, common to all vertebrates, including man.