Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Small change for a big improvement – halogen bonds and drug discovery

Halogen bonding has been applied in crystal engineering, materials research, and nanotechnology for some time. Scientists from the Heidelberg Institute for Theoretical Studies (HITS) and the Czech Academy of Science in Prague have now developed a new tool to use halogen bonds for drug discovery applications.

Halogen chemistry has been exploited by medicinal chemists for nearly 70 years. To date, halogens were regarded useful for optimization of so-called ADMET properties (the acronym stands for absorption, distribution, metabolism, excretion, toxicity) – they improve oral absorption and facilitate crossing biological barriers by prospective drugs, they are useful for filling small hydrophobic cavities present in many protein targets, and they prolong lifetime of the drug.

Left panel: the charge distribution around the bromobenzene molecule. The regions of negative electrostatic potential are in blue, positive regions in grey. The grey disc in the forefront represents the ?-hole. Right panel: the overlay of the predicted binding poses of K17 inhibitor of casein kinase 2 (PDB code 2OXY) with (red) and without (blue) explicit sigma-holes (ESH) and comparison with the crystal structure (grey).
Image: Agnieszka Bronowska / HITS

In short: They make compounds of interest more drug-like. However, direct interactions mediated by halogen atoms have been much ignored in pre-clinical drug development.

Recently, scientists from Heidelberg and Prague, working in quantum chemistry and structure-based drug design, have developed a new tool for the usage of halogen bonds for computational medicinal chemistry and drug discovery applications. The study, led by Dr. Agnieszka Bronowska from the Heidelberg Institute for Theoretical Studies (HITS) and conducted in cooperation with scientists from the Czech Academy of Sciences, has been published in Chemical Communication.
Most halogens - except fluorine - have unique properties which allow them to stabilize direct interaction between prospective drugs and their protein targets. These properties are of quantum-chemical origin; namely, the anisotropy of charge distribution around the halogen atom, when it is bound to an electron-withdrawing substrate. Unexpectedly, despite of being negatively charged, halogens have regions which remain positively charged (Figure 1, left panel). These regions, called sigma-holes, are responsible for the directional and stabilizing character of halogen bonding with other electronegative atoms, such as oxygen or nitrogen.
Overlooking sigma-holes leads to errors in predictions of structure and energetics of drug-protein complexes and thus to failure in drug development.

By approximating the positively charged sigma-hole with a massless, charged pseudo-atom (denoted as explicit sigma-hole or ESH), Agnieszka Bronowska and her colleagues incorporated a quantum-chemical effect into faster (and much less accurate) computational methods applicable to structure-based drug design. “We tested nearly a hundred complexes between medicinally relevant proteins and halogenated molecules”, Bronowska says. “The results showed significant improvement in the description of such complexes upon introduction of ESH.”
The new method is already used by research groups in the Czech Republic, in the United Kingdom and in the U.S. for designing novel compounds to treat chemotherapy-resistant cancers, infectious diseases, and Alzheimer’s disease.

Scientific Publication:
Plugging the explicit sigma-holes in molecular docking. Michal Kolár, Pavel Hobza and Agnieszka K. Bronowska. Chem. Commun., 2013,49 (10), 981-983
DOI: 10.1039/C2CC37584B

Scientific Contact:
Dr. Agnieszka Bronowska
Molecular Biomechanics Group (MBM)
Heidelberg Institute for Theoretical Studies (HITS)
Press Contact:
Dr. Peter Saueressig
Public Relations
Heidelberg Institute for Theoretical Studies (HITS)
Phone: +49-6221-533245

Dr. Peter Saueressig | idw
Further information:

More articles from Life Sciences:

nachricht First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife

nachricht Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

Advanced analysis of brain structure shape may track progression to Alzheimer's disease

26.10.2016 | Health and Medicine

More VideoLinks >>>