Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biochemical ‘On-Switch' Could Solve Protein Purification Challenge

22.10.2009
Drugs based on engineered proteins represent a new frontier for pharmaceutical makers. Even after they discover a protein that may form the basis of the next wonder drug, however, they have to confront a long-standing problem: how to produce large quantities of the protein in a highly pure state. Now, a multi-institutional research team including a biochemist at the National Institute of Standards and Technology (NIST) may have found* a new solution in an enzymatic "food processor" they can activate at will.

The team has found an efficient method of harvesting purified protein molecules by altering an enzyme that soil bacteria use to break down their food. In its natural form, this enzyme would be of little use to drug developers, but the team has modified it so that it can be activated at the desired moment.

By creating essentially an "on-switch" for the enzyme's activity, the team has found a way to separate a single, desired protein from the mixture of thousands generated by a living cell, which remains biotechnology's natural protein factory of choice.

Bacteria use the enzyme, called subtilisin, as a sort of food processor: After producing it internally, they release the enzyme into the soil, where it uses a minuscule "blade" to chop up proteins into digestible pieces. Because it could damage the bacterium's interior, the blade has a protective sheath that only comes off once the enzyme has exited the cell.

"The enzyme and sheath are strongly attracted to each other. The enzyme's first act is to cut the sheath away," says NIST's Travis Gallagher. "The method takes advantage of their attraction in order to isolate the protein we want."

The team first creates many "sheathless" copies of the enzyme, which are modified to function only in the presence of a triggering molecule such as fluoride. The modified enzymes are bound to the surface of a strainer. Then the team uses engineered cells to generate mass quantities of a potentially therapeutic protein, each copy of which has a subtilisin sheath attached to it. After harvesting these proteins along with the thousands of others that grow in the cellular interior, they filter the mixture through the strainer, where the protein-sheath pairs are caught and stuck fast to the subtilisin while the rest of the mixture drains away.

At this point, the team flicks their switch. They add a bit of fluoride and the enzyme snips the bond between sheath and protein, releasing the desired protein free of almost all impurities. "The technique can conceivably be used to obtain any protein you like, and the process is repeatable, as the sheaths can be removed for another round of purification," Gallagher says. "For most proteins, the method can achieve greater than 95 percent purity at a single step."

The research team also includes members from Potomac Affinity Proteins, LLC (PAP) and the University of Maryland Biotechnology Institute (UMBI). UMBI holds the patent, which has been licensed to PAP. The research was supported by grants from the National Institutes of Health and the Bill and Melinda Gates Foundation.

Chad Boutin | Newswise Science News
Further information:
http://www.nist.gov

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

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...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

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...

Im Focus: Deep inside Galaxy M87

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...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

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...

Im Focus: Microprocessors based on a layer of just three atoms

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>