Evolution of Shake Flask Technology: Novel Product Introductions Offer Advantages by Increasing DNA and Protein Production

Novel Product Introductions Offer Advantages by Increasing DNA and Protein Production Before and for a time after the research career of Louis Pasteur, microbiology essentially remained a static task. Glass bottles would rest on shelves until the contents were analyzed. This all changed in 1949, when the Nobel Prize was awarded for the development of the antibiotic streptomycin. When the developers of streptomycin published a journal article to herald their accomplishment, they took the opportunity to share their frustration about the slow growth of the actinobacterium, Streptomyces, in static culture. They pointed out that by employing a new invention—a shaker—cell culture reactions would speed up.For a culture vessel, the scientists simply chose what was available in the lab: it happened to be an Erlenmeyer flask. Nobel Prizes always attract much attention, so the demand for commercially manufactured shaking machines, that is, Erlenmeyer flasks, for microbiology purposes grew rapidly. If we inoculate a static culture with bacteria or eukaryotic cells, the cells will invariably sink to the bottom and start to consume nutrients and oxygen. Nutrients are readily available from the medium, but the oxygen is quickly depleted. More oxygen is available in the gas phase above the medium, but the oxygen needs to pass through the liquid and reach the cells. This takes time and results in a gradient: oxygen is available on top, but there are no cells in this layer. Oxygen is scarce at the bottom, where it is actually needed.