Two of the most urgent challenges for scientists are the battles against food shortages and infectious diseases like malaria.
Unfortunately, both the herbicides used to protect plants and the anti-infectives that shield us from disease rapidly lose their effectiveness as the target organisms develop resistance.
In order to benefit both fields at once, scientists tested lead compounds from agrochemical research against infectious germs as well. In this way, a team of German and Swiss researchers has found a new candidate that may work against malaria, as they report in the journal Angewandte Chemie.
“Recently, enzymes from the non-mevalonate terpene biosynthetic pathway have been identified as attractive target structures with novel modes of activity for the development of herbicides and drugs against infectious diseases,” explains François Diederich from the ETH Zurich (Switzerland).
“This biosynthetic pathway is found in many human pathogens and in plants, but does not occur in mammals.” Correspondingly, an inhibitor should only have a toxic effect on pathogens and plants, not humans. Diederich and his co-workers at the ETH, TU Munich, BASF-SE, the University of Hamburg, the Swiss Tropical Institute STPHI in Basel, and TU Dresden have now discovered new inhibitors and characterized the ways in which they work.
By using high-throughput screening methods, the researchers of BASF SE led by Matthias Witschel tested about 100,000 compounds for an inhibitory effect against plant IspD, an enzyme of the aforementioned non-mevalonate terpene biosynthetic pathway – and found several hits.
The most interesting compounds are pseudilins, highly halogenated alkaloids from marine bacteria, and have a significant inhibitory effect on IspD, as researchers at the TU Munich led by Michael Groll demonstrated in NMR-based tests and researchers at the University of Hamburg led by Markus Fischer showed in photometric tests. Says Groll: “Interestingly, the chemical scaffold of the pseudilins is completely different from that of a previously discovered IdpD inhibitor. This suggests that the mode of action should also be different.”
To research this mechanism, Andrea Kunfermann from Groll’s team synthesized cocrystals of the pseudilins and IspD enzymes and examined them by X-ray crystallography. This showed that the pseudilins bind to an allosteric pocket in the enzyme. Halogen atoms in the pseudilins build up halogen bridges to the enzyme, which are, in addition to metal ion coordination, responsible for the strong binding. Occupation of this pocket changes the shape of the enzyme so that a cosubstrate required for proper functioning of the enzyme can no longer dock at the binding site in the active center.
“The pseudilins demonstrated herbicidal activity in plant assays and were active against Plasmodium falciparum, the pathogen that causes Malaria tropica and is dependent on the non-mevalonate biosynthesis pathway for survival,” reports Diederich. The researchers hope to use this as a new starting point for malaria treatment.About the Author
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201309557
Moth takes advantage of defensive compounds in Physalis fruits
26.08.2016 | Max-Planck-Institut für chemische Ökologie
Designing ultrasound tools with Lego-like proteins
26.08.2016 | California Institute of Technology
Scientists and engineers striving to create the next machine-age marvel--whether it be a more aerodynamic rocket, a faster race car, or a higher-efficiency jet...
Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.
In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...
Electrochemists at TU Graz have managed to use monocrystalline semiconductor silicon as an active storage electrode in lithium batteries. This enables an integrated power supply to be made for microchips with a rechargeable battery.
Small electrical gadgets, such as mobile phones, tablets or notebooks, are indispensable accompaniments of everyday life. Integrated circuits in the interiors...
Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature, according...
A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers.
25.08.2016 | Event News
24.08.2016 | Event News
12.08.2016 | Event News
26.08.2016 | Health and Medicine
26.08.2016 | Earth Sciences
26.08.2016 | Life Sciences