Biochromatograms showing the effect of adding phenylacetate to a Penicillium chrysogenum culture medium

Photograph of biochromatograms titled ‘Effect of adding phenylacetate to a Penicillium chrysogenum culture medium’, showing the stimulation of benzylpenicillin production by the addition of side chain precursor phenylacetate to a Penicillin chrysogenum fermentation, carried out in Martin Cole’s laboratory Microbiology Department, Beecham Research Laboratories, Brockham Park

Biochromatograms are an example of chromatographs which show the separation of peptides and proteins. In this example, paper strip chromatograms were laid on sheets of agar on large glass plates seeded with Bacillus sublitis and incubated overnight. The dark zones are areas of inhibited bacterial growth (i.e. clear areas letting light through to a sheet of photographic paper placed underneath and illuminated from above).

Research in 1957 by the team at Beecham Research Laboratories led to the development of several semi-synthetic penicillins. By tweaking 6 aminopenicillanic acid's chemical structure, scientists created medicines to treat a wider range of bacterial infections, with fewer side effects.

Martin Cole was a microbiologist, whose career at Beecham Research Laboratories focused on the hope of developing and using semi-synthetic penicillins, including cloxacillin and amoxicillin. He led the team which first discovered and named olivanic acids and clavulanic acid and then combined the latter with amoxicillin, to produce co-amoxiclav, brand name Augmentin.