Biochromatogram showing penicillins present in a Penicillium chrysogeum culture

Original biochromatogram print, titled ‘Ether chromatograms of penicillins present in a Penicillium chrysogeum culture’, dated 20 November 1959, carried out in Martin Cole’s laboratory, Department of Microbiology, Beecham Research Laboratories, Brockham Park, showing the effect of treatment with Streptomyces amidase enzyme on penicillins and an analysis of a culture sample from a 500 gallon scale fermentation

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).

This example shows the penicillins produced by a strain of showing the effect of Penicillium chrysogenum grown in two types of culture media in shaker flasks and effect of treatment with Streptomyces amidase enzyme and an analysis of a culture sample from a 500 gallon scale fermentation. The paper strip chromatograms were run using the ether solvent system and contacted with Bacillus subtilis seed agar to reveal zones of antibacterial activity. P1 shows a culture grown in corn steep liquor/lactalose culture medium, P2 shows a culture grown in a peanut based medium. A1 and A2 were the P1 and P2 samples treated with Streptomyces amidase enzyme. R.orig is the sample from a 500 gallon fermenter and R. extracted is the residue after solvent extraction process.

This 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.