Oxford chemists filmed the enzyme that builds penicillin — and solved a 40-year-old puzzle

Eighty years after Oxford scientists turned penicillin into a medicine that saved countless lives, researchers there have finally watched nature assemble it. Using X-ray lasers, the team captured a frame-by-frame 'molecular movie' of the enzyme isopenicillin N synthase snapping penicillin's famous ring into place — a reaction step that vanishes in fractions of a second and had eluded chemists for four decades. Published in Nature Catalysis, the work could guide the design of new antibiotics at a moment when one in six bacterial infections resists existing drugs.