Even fungus molds need sex once in a while, provided that scientists set the right mood. Since the initial research into Penicillium chrysogenum, a century ago, it was long believed that the penicillin-producing fungus mold reproduced only by spores. Spores spread by getting caught in the wind, moving through water, or attaching to the fur of an animal.
However, recent findings by an international research team at Ruhr-Universitat determined that P. chrysogenum has a sexual cycle, as in, two genders and is able to reproduce sexually. The efforts to urge new ways for the mold to reproduce resulted in biotechnologically beneficial outcomes, including a strain of P. chrysogenum able to produce higher than normal amounts of penicillin.
P. chrysogenum remains of vital importance to medicine, as it is the only known producer of penicillin, making it the most valuable fungus on the planet. Alexander Fleming first demonstrated the formation of penicillin in P. chrysogenum, around 100 years ago, which usually occur as molds, appearing white, green, or black on spoiled food.
When P. chrysogenum reproduces via spores, the resulting offspring only contain the genes of one fungal parent. Usually the domain of plants and animals, there are a minority of microorganisms, like algae and fungi, who have been documented with the ability to reproduce sexually.
‘Five years ago we already detected the existence of so-called sex genes in Penicillium chrysogenum,’ said Prof. Ulrich Kück, one of the lead authors on the soon to be published research paper.
Kück’s team has identified specific conditions in which P. chrysogenum may reproduce sexually. When the fungal strain breeds in a dark, oxygen deprived environment, the fungus is driven to reproduce via sex, with the resulting offspring showing changes at the molecular level, as well as in their phenotype. The team reported administering a nutrient for the mold as well, supplementing it with the the vitamin biotin.
‘We presume that the findings can also be applied to other fungi,’ said Kück, whose team used microarray analysis to investigate the 12,000 genes of the fungus.
Image: Lehrstuhl Allgemeine und Molekulare Botanik, RUB
Source: Böhm J, Hoff B, O’Gorman CM, Wolfers S, Klix V, Binger D, Zadra I, Kürnsteiner H, Pöggeler S, Dyer PS, & Kück U (2013). ‘Sexual Reproduction and Mating-Type – Mediated Strain Development in the Penicillin-Producing Fungus Penicillium Chrysogenum’ PNAS : 10.1073/pnas.1217943110