Molds are able to reproduce sexually, unlike we thought for 100 years

Jan 08, 2013 by Dr. Julia Weiler
Scanning electron microscopic image of asexual conidiospores from the penicillin producer Penicillium chrysogenum © Lehrstuhl Allgemeine und Molekulare Botanik, RUB

For over 100 years, it was assumed that the penicillin-producing mould fungus Penicillium chrysogenum only reproduced asexually through spores. An international research team led by Prof. Dr. Ulrich Kück and Julia Böhm from the Chair of General and Molecular Botany at the Ruhr-Universität has now shown for the first time that the fungus also has a sexual cycle, i.e. two "genders". Through sexual reproduction of P. chrysogenum, the researchers generated fungal strains with new biotechnologically relevant properties - such as high penicillin production without the contaminating chrysogenin.

The team from Bochum, Göttingen, Nottingham (England), Kundl (Austria) and Sandoz GmbH reports in PNAS. The article will be published in this week's Online Early Edition and was selected as a cover story.

Only penicillin producer

About 100 years ago, demonstrated the formation of penicillin in Penicillium chrysogenum. To date, there is no other known producer of the antibiotic penicillin, which has an annual global market value of about six billion Euros.

Combining genes and breeding offspring with new properties

Not only animals and plants, but also many microorganisms such as fungi and algae can reproduce sexually. The advantage: the progenies possess a combination of genes from both mating partners and thus have new properties. in fungi is, however, not the rule. Most reproduce via which, in the case of moulds, occur as white, green or black deposits on spoiled food. These spores only bear the genes of one parent fungus. "Five years ago we already detected the existence of so-called sex genes in Penicillium chrysogenum", says Prof. Kück. Now, the researchers have discovered specific environmental conditions in which the fungus actually reproduces sexually. The decisive thing was to breed fungal strains in the dark under conditions in a nutrient medium supplemented with the vitamin biotin. The offspring exhibited new properties, both at the molecular level, as well as in their phenotypes.

Results could be applicable to other fungi

Using so-called microarray analysis, the biologists also investigated the activity of all the approximately 12,000 genes of the mould . The result: the sex genes control the activity of biologically relevant genes, for example those for penicillin production. "We presume that the findings can also be applied to other fungi", says Ulrich Kück, "such as Penicillium citrinum and Aspergillus terreus that produce cholesterol-lowering statins, or Penicillium brevicompactum and Tolypocladium inflatum, which produce immunosuppressives that are used in all organ transplantations". The researchers conducted the work in the Christian Doppler Laboratory "Biotechnology of Fungi" at the Ruhr-Universität with funding from the Christian Doppler Society (Vienna).

Explore further: Researchers successfully clone adult human stem cells

More information: J. Böhm, B. Hoff, C.M. O'Gorman, S. Wolfers, V. Klix, D. Binger, I. Zadra, H. Kürnsteiner, S. Pöggeler, P.S. Dyer, U. Kück (2013): Sexual reproduction and mating-type – mediated strain development in the penicillin-producing fungus Penicillium chrysogenum, PNAS, DOI: 10.1073/pnas.1217943110

add to favorites email to friend print save as pdf

Related Stories

Fleming's fungus still surprising scientists

Nov 21, 2011

(PhysOrg.com) -- From the moment that a spore of fungus fell onto Alexander Fleming's culture plate in 1928 and killed the bacteria around it, that fungus was destined to become one of the most studied organisms ...

Sex life of killer fungus finally revealed

Dec 01, 2008

Biologists at The University of Nottingham and University College Dublin have announced a major breakthrough in our understanding of the sex life of a microscopic fungus which is a major cause of death in immune deficient ...

Recommended for you

Researchers successfully clone adult human stem cells

Apr 18, 2014

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

Researchers develop new model of cellular movement

Apr 18, 2014

(Phys.org) —Cell movement plays an important role in a host of biological functions from embryonic development to repairing wounded tissue. It also enables cancer cells to break free from their sites of ...

User comments : 0

More news stories

Biologists help solve fungi mysteries

(Phys.org) —A new genetic analysis revealing the previously unknown biodiversity and distribution of thousands of fungi in North America might also reveal a previously underappreciated contributor to climate ...

Making graphene in your kitchen

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.