Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


A new synthetic amino acid for an emerging class of drugs


One of the greatest challenges in modern medicine is developing drugs that are highly effective against a target, but with minimal toxicity and side-effects to the patient.

Such properties are directly related to the 3D structure of the drug molecule. Ideally, the drug should have a shape that is perfectly complementary to a disease-causing target, so that it binds it with high specificity. Publishing in Nature Chemistry, EPFL scientists have developed a synthetic amino acid that can impact the 3D structure of bioactive peptides and enhance their potency.

Peptides and proteins as drugs

Many of the drugs we use today are essentially naturally-occurring peptides (small) and proteins (large), both of which are made up with the amino acids found in all living organisms. Despite the enormous variety of peptides and proteins, there are only twenty natural amino acids, each with a different structure and chemical properties. When strung together in a sequence, amino acids create peptides and proteins with different 3D structures and, consequently, different biological functions.

... more about:
»EPFL »Ecole »Polytechnique »amino »cysteine »drugs »proteins »receptor

Until recently, the vast majority of amino acid-based drugs were the kinds occurring in nature: hormones such as insulin, antibiotics such as vancomycin, immunosuppressive drugs such as cyclosporine etc. But the mounting burden of diseases means that newer and more effective medications must be developed; for example, bacterial resistance is growing globally, pushing our need for novel antibiotics. One way to address this need is the cutting-edge field of directed evolution, which mimics natural selection in the lab to evolve and develop new peptides and proteins.

A new amino acid for new peptides

The team of Christian Heinis at EPFL has developed a synthetic amino acid whose unique structure can considerably increase the effectiveness of therapeutic peptides and proteins. The synthetic amino acid has a very similar structure to a natural amino acid called cysteine. Cysteine is unique among the twenty natural amino acids because it contains a sulfur group. This allows it to form a bridge with another cysteine, and thereby influence the overall 3D structure – and function – of a peptide or protein.

The EPFL researchers initially designed five cysteine-like amino acids, all with one crucial change: each one could form two bridges instead of just one. The team achieved this by replacing cysteine's single sulfur group with a branch containing two sulfur groups. After synthesizing the five new amino acids, the team integrated them into the structure of two bioactive peptides, one that inhibits an enzyme implicated in cancer, and one blocking a receptor found in neurons.

Testing only a handful of cyclic peptides with the synthetic amino acid, Heinis' team was able to identify several peptides that showed enhanced activities. The best inhibitor of the neuron receptor was 8-fold improved and the best protease inhibitor had even a 40-fold higher activity.

"This was unexpected", says Christian Heinis. "Usually when you tamper with a natural molecule, you end up making it worse. In this case, we found the exact opposite, which is very exciting."

The emerging class of bicyclic peptides

The team focuses on therapeutics, where they have a strong background in developing "bicyclic" peptides – peptides that contain two rings in their structure. Bicyclic peptides have grown into a new class of therapeutic peptides that can be used on disease target that conventional small molecules or large antibodies cannot reach. Heinis' group has generated bicyclic peptides against a range of disease targets using directed evolution. "In our work with bicyclic peptides, we learned that wide structural diversity in peptide libraries is key for achieving good binding. With this new amino acid, it is possible to produce highly diverse peptide structures."

Heinis aims now to use the new amino acid in directed evolution experiments. Its structural features and its ability to efficiently make cyclic peptides makes the synthetic amino acid a promising candidate for developing new, effective polycyclic peptides for targeted therapy.



Chen S. Gopalakrishnan R, Schaer T, Marger F, Hovius R, Bertrand D, Pojer F, Heinis C. Di-thiol amino acids can structurally shape and enhance the ligand-binding properties of polypeptides. Nature Chemistry 31 August 2014. DOI: 10.1038/nchem.2043

Nik Papageorgiou | Eurek Alert!
Further information:

Further reports about: EPFL Ecole Polytechnique amino cysteine drugs proteins receptor

More articles from Life Sciences:

nachricht Two decades of training students and experts in tracking infectious disease
27.11.2015 | Hochschule für Angewandte Wissenschaften Hamburg

nachricht Increased carbon dioxide enhances plankton growth, opposite of what was expected
27.11.2015 | Bigelow Laboratory for Ocean Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Climate study finds evidence of global shift in the 1980s

Planet Earth experienced a global climate shift in the late 1980s on an unprecedented scale, fuelled by anthropogenic warming and a volcanic eruption, according to new research published this week.

Scientists say that a major step change, or ‘regime shift’, in the Earth’s biophysical systems, from the upper atmosphere to the depths of the ocean and from...

Im Focus: Innovative Photovoltaics – from the Lab to the Façade

Fraunhofer ISE Demonstrates New Cell and Module Technologies on its Outer Building Façade

The Fraunhofer Institute for Solar Energy Systems ISE has installed 70 photovoltaic modules on the outer façade of one of its lab buildings. The modules were...

Im Focus: Lactate for Brain Energy

Nerve cells cover their high energy demand with glucose and lactate. Scientists of the University of Zurich now provide new support for this. They show for the first time in the intact mouse brain evidence for an exchange of lactate between different brain cells. With this study they were able to confirm a 20-year old hypothesis.

In comparison to other organs, the human brain has the highest energy requirements. The supply of energy for nerve cells and the particular role of lactic acid...

Im Focus: Laser process simulation available as app for first time

In laser material processing, the simulation of processes has made great strides over the past few years. Today, the software can predict relatively well what will happen on the workpiece. Unfortunately, it is also highly complex and requires a lot of computing time. Thanks to clever simplification, experts from Fraunhofer ILT are now able to offer the first-ever simulation software that calculates processes in real time and also runs on tablet computers and smartphones. The fast software enables users to do without expensive experiments and to find optimum process parameters even more effectively.

Before now, the reliable simulation of laser processes was a job for experts. Armed with sophisticated software packages and after many hours on computer...

Im Focus: Quantum Simulation: A Better Understanding of Magnetism

Heidelberg physicists use ultracold atoms to imitate the behaviour of electrons in a solid

Researchers at Heidelberg University have devised a new way to study the phenomenon of magnetism. Using ultracold atoms at near absolute zero, they prepared a...

All Focus news of the innovation-report >>>



Event News

Fraunhofer’s Urban Futures Conference: 2 days in the city of the future

25.11.2015 | Event News

Gluten oder nicht Gluten? Überempfindlichkeit auf Weizen kann unterschiedliche Ursachen haben

17.11.2015 | Event News

Art Collection Deutsche Börse zeigt Ausstellung „Traces of Disorder“

21.10.2015 | Event News

Latest News

Siemens to supply 126 megawatts to onshore wind power plants in Scotland

27.11.2015 | Press release

Two decades of training students and experts in tracking infectious disease

27.11.2015 | Life Sciences

Coming to a monitor near you: A defect-free, molecule-thick film

27.11.2015 | Materials Sciences

More VideoLinks >>>