Venom Destroys Fungi

a dark brown thick-tailed scorpion with its tail positioned up over its head, standing in brownish red dry dirt

Biological Strategy

AskNature Team

Image: Bernard Dupont / Wikimedia Commons / CC BY - Creative Commons Attribution alone

Protect From Fungi

Fungi–which include molds and mushrooms, amongst others–play important roles in every ecosystem, but can also create diseases in plants and animals. Fungi can rapidly reproduce, so living systems must fend them off early to avoid their spread and potential, physical harm. Living systems use both physical and chemical strategies to protect from fungi, and must ensure that these strategies don’t harm the threatened living system itself. For example, a pumpkin’s skin has antifungal proteins to prevent fungal growth without harming the pumpkin itself.

Search this Function

Protect From Microbes

In living systems, microbes play important roles, such as breaking down organic matter and maintaining personal and system health. But they also pose threats. Bacteria can be pathogens that cause diseases. Some bacteria create colonies called biofilms that can coat surfaces, reducing their effectiveness–for example, inhibiting a leaf’s ability to photosynthesize. Living systems must have strategies for protecting from microbes that cause disease or become so numerous that they create an imbalance in the system. At the same time, living systems must continue living in harmony with other microbes. Some living systems kill microbes. Others repel without killing to reduce the chances that microbes will adapt to the lethal strategy and become resistant to it. For example, some pea seedlings exude a chemical that inhibits biofilm buildup.

Search this Function

Arachnids

Class Arachnida (“spider”): Spiders, mites, ticks, scorpions

Arachnids get a bad reputation, but they play an important role in the ecosystem by controlling insect populations. Almost half of the species in the class are spiders, and most live in terrestrial environments. Unlike insects, most arachnids have two body sections: the cephalothorax, which is the head and thorax fused together, and the abdomen. Mites and ticks, on the other hand, have only one body section that is relatively flat. This body shape comes in handy for the species that are parasitic, because it makes it harder for their hosts to bite or scratch them off.

Search this Living System

The venom of the thick-tailed scorpion protect it from fungal parasites by containing antifungal, antimicrobial proteins that work synergistically when applied to its own body.

Fungal infections represent major threats to agriculture. In fact, pathogenic fungi are responsible for 35% of all crop loss worldwide. Developing new fungicides is of paramount importance. Tityus discrepans scorpions are extremely susceptible to fungal infections because of their habitat. In order to cope, they spray themselves with their own venom. The complex mixture contains numerous compounds with antifungal and antimicrobial properties. Some function by interfering with fungal cell wall development and others by altering membrane permeability. The synergistic effect of all of the antifungal proteins acting in concert makes the venom a potent fungicide.

Chemicals in Oregano Act as Fungicide

Oregano

Volatile compounds found in oregano destroy fungi by breaking down their cell membranes.

Last Updated August 23, 2016

References

“Seven toxins (F1-F7) were purified from Tityus discrepans scorpion venom…The compounds were fungitoxic on Macrophomina phaseolina…It is not known if F1 is a small peptide or some other kind of organic molecule. Compounds F2-F7 were peptides. The most potent was F7…The peptides affect M. phaseolina viability by three mechanisms: decreasing esterase activity, altering Na⁺ membrane permeability, and altering wall sterol biosynthesis. It seems that interfering with sterol synthesis is an important mechanism behind the effect of the fungicideal toxins. However, the antifungal effects at short times are indicative of a direct esterase inhibition, which, with the increased membrane leakiness to Naþ, makes the fungus inviable…Phytopathogenic fungi cause 35% of worldwide crop loss. Macrophomina phaseolina is a globally distributed Ascomycote able to infect a wide range of crops…It has become resistant to many chemical fungicides in current use…species, such as Tityusdiscrepans, spray their venom on their bodies to clean it from lichens, fungi, and bacteria…Scorpion venom compounds could be useful as biodegradable fungicides.” (Joya et al. 2011:6327)

“M. phaseolina underwent gross structural changes after exposure to F1, F2, F5, and F7. These toxins induced chitin increase along the hyphae…Fungi under the action of F2 and F7 showed a considerable enhancement of septum thickness. Increments in chitin may be due to activation of chitin synthases…M. phaseolina exposure to F3, F4, F5, and F6 resulted in a decrease of the intracellular Na…Shunting bacterial and fungal membrane permeability is an efficient way to kill prokaryonts…” (Joya et al. 2011:6334)

“Interfering with sterol synthesis is an important mechanism behind the effect of the antifungal T. discrepans venom components described here…An outstanding feature of the toxins isolated in this work is that they seem to attack simultaneously two or more targets fundamental for M. phaseolina survival.” (Joya et al. 2011:6335)

Journal article

Scorpion Toxins Modify Phytopathogenic Fungus Physiology. A Possible Source of New Fungicides

J. Agric. Food Chem. | 21/04/2011 | Galax Joya, Gina D’Suze, Víctor Salazar, Arnaldo Rosales, Carlos Sevcik, Gonzalo Visbal, André T. S. Ferreira, Jonas Perales

embedly preview

AskNature