Writing in the current issue (Sept. 9, 2007) of the journal Nature Chemical Biology, a team of researchers from the UW-Madison School of Pharmacy describes a novel enzyme capable of changing the chemical properties of a variety of existing drugs and small molecules to make new agents to treat cancer and fight infection.
"We're finding this enzyme glycosylates all sorts of molecules," says Jon Thorson, a UW-Madison professor of pharmaceutical sciences describing the process of adding natural sugar molecules to other chemical molecules to enhance their biological effects.
The newly evolved enzyme developed by Thorson and colleagues Gavin. J. Williams and Changsheng Zhang, according to Thorson, is akin to a "Swiss Army enzyme," a catalyst that can decorate many different chemical molecules with all sorts of sugars to alter their biological effects.
Enzymes are proteins that act as catalysts across biology, from single-celled organisms to humans. They promote chemical reactions in cells and are used widely in industry for everything from making beer and cheese to producing paper and biofuel.
They are also important for making so-called natural drugs, therapeutic agents based on the blueprints of chemicals produced in nature by plants and microorganisms. Such natural sugar-bearing chemicals are the basis for some of medicine's most potent antibiotics and anticancer drugs as exemplified by the antibiotic erythromycin and the anticancer drug doxorubicin.
Important chemical features of such drugs are natural sugars, molecules that often determine a chemical compound's biological effects. Although scientists can sometimes manipulate how sugars are added or subtracted to a chemical molecule to alter its therapeutic properties, it is difficult and not always possible to routinely modify them to enhance their beneficial effects.
The new enzyme was created by generating random mutations in genes that make a naturally occurring enzyme. The altered genes were then put into a bacterium, which fabricated a series of randomly mutated new enzymes. These enzyme variants were then tested in a high throughput screen where chemical molecules engineered to fluoresce stop glowing when a sugar is successfully attached.
"We're transferring the sugar to a beacon," Thorson explains. "When you attach a sugar, you shut off the fluorescence."
The development of the screen, according to Thorson, was critical, overcoming a key limitation in the glycosyltransferase field.
"We're assaying hundreds of very interesting drug-like molecules now with newly evolved glycosyltransferases. The ability to rapidly evolve these enzymes has opened a lot of doors."
The range of potential therapeutic agents that might be generated with the new technology includes important anti-inflammatory and anti-cancer compounds, and antibiotics.
What's more, the work could lead to the creation of a "super bug," an engineered bacterium that can perform the entire process in a laboratory dish: "There's no doubt that this is going to work in vivo," says Thorson. "We can create a bug where you feed it sugars and the compounds you want to hang those sugars on" to arrive at new medicines.
Jon Thorson | EurekAlert!
Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz
Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences