- Person
- Ferdinand Cohn
- Lived
- 1828–1898
- Field
- Microbiology & botany
- From
- German (Prussian Silesia)
The story
Ferdinand Cohn, born in 1828 to a poor Jewish family in Breslau, now Wrocław in Poland, was a botanist who became one of the founders of modern bacteriology. Barred because he was Jewish from taking a doctorate at his home university, he earned it in Berlin in 1847 and then built his career back in Breslau, where in 1866 he founded an Institute of Plant Physiology.
In the mid nineteenth century, bacteria were still poorly understood. Cohn set out to bring order to them, and he sorted them into groups by shape: spheres, short rods, threads and spirals. This simple system for describing bacteria by their form is still in use, and it gave scientists a shared language for the microbes they were seeing under the microscope.
In 1872 Cohn founded a journal, Beiträge zur Biologie der Pflanzen (Contributions to the Biology of Plants), where he published many of his own findings on bacteria. It soon carried a paper that would change medicine.
Robert Koch, a physician, had been studying anthrax, a deadly disease of livestock that can also kill people. He wrote to Cohn asking to show his evidence, and travelled to Breslau to demonstrate it. Koch convinced Cohn and his colleagues that the bacterium Bacillus anthracis was the cause of anthrax. Koch had also found that the anthrax bacterium forms spores that can lie dormant and later cause disease. Cohn was impressed, supported Koch's research and published his anthrax paper in his journal in 1876.
That paper is a landmark in the germ theory of disease: it showed that a specific microbe causes a specific illness. With Cohn's backing, Koch went on to become one of the great figures of medicine, developing methods for studying bacteria that laboratories still build on.
Cohn's gift was twofold. He brought order to the study of bacteria, and he recognised a talented researcher and gave his work a platform. Cohn died in 1898, but the science of identifying the microbes that cause disease, and therefore of preventing and treating infections, grew directly from the work he did and the work he championed.
Why it matters
Cohn's system for describing bacteria and his backing of Koch's anthrax research helped lay the groundwork for identifying the germs behind disease, which underpins modern infection control.
About Ferdinand Cohn
Breslau botanist, barred from a doctorate at home as a Jew, who classified bacteria, discovered heat-resistant spores and championed Robert Koch, becoming a founder of bacteriology.
More about Ferdinand Cohn
Sources
- Ferdinand Julius Cohn EBSCO Research Starters
- Ferdinand Cohn Wikipedia
- Robert Koch Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.