Background
Sandwiched culture
Wednesday 26 September 2012

In the Journal of Microbiological Methods, Leiden biologists Inez de Jong and Dennis Claessen describe a new method of cultivating the bacterium Streptomyces coelicolor. Normally, if you grow this species on a Petri dish, it will be exposed to air and consequently produce all sorts of substances such as antibiotics and fungicidal molecules. Which is great for the pharmaceutical industry but a nuisance if you are interested in what this bacterium does when it is not exposed to air.

Accordingly, the biologists warmed the bacterial colony in an oven, and then covered it with a cellophane plate. The Streptomyces grow more slowly in this "sandwiched culture" but they don't get up to any of tricks they perform when they are grown on a single plate, making it easier to find out how those tricks work.