Plants, bacteria and various fungi produce a specific group of hormones known as auxins. Together with other hormones, they cause plant cells to stretch and thus, for example, the rapid growth of young shoots. The manner in which plants produce these substances has been intensively studied for decades, and is accordingly described in great detail. In contrast, how this biosynthesis takes place in fungi has hardly been studied to date. Researchers already know that some species of fungi which are plant pests are able to produce auxins, which trigger the growth of harmful tissue in their host plants. Now, for the first time, Professor Frank Kempken, head of the Department of Genetics and Molecular Biology at Kiel University, together with his working group, has described the mechanism by which the mould Neurospora crassa produces auxins. The Kiel researchers have also shown that fungi which are not harmful organisms are also able to make these growth hormones. Their findings have now been published in the scientific journal PLoS One.