Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Methuselah enzymes: SEN and the art of molecule maintenance

02.04.2004


Single-enzyme nanoparticles, or SENs, left, and their thinner cousins, right, remain active for up to 143 days, thanks to their protective caging. (J.B. Kim, Pacific Northwest National Laboratory.)


Lab discovers way to keep short-lived catalysts active for longer than five months

Enzymes, the workhorses of chemical reactions in cells, lead short and brutal lives. They cleave and assemble proteins and metabolize compounds for a few hours, and then they are spent.

This sad fact of nature has limited the possibilities of harnessing enzymes as catalytic tools outside the cell, in uses that range from biosensing to toxic waste cleanup.



To increase the enzyme’s longevity and versatility, a team at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Wash., has caged single enzymes to create a new class of catalysts called SENs, or single enzyme nanoparticles. The nanostructure protects the catalyst, allowing it to remain active for five months instead of hours.

"The principal concept can be used with many water-soluble enzymes," said Jungbae Kim, PNNL senior scientist who described the feat here today at the national meeting of the American Chemical Society.

"Converting free enzymes into these novel enzyme-containing nanoparticles can result in significantly more stable catalytic activity," added Jay Grate, PNNL laboratory fellow and SENs co-inventor.

Kim and Grate, working in the W.R. Wiley Environmental Molecular Sciences Laboratory at PNNL, modified a common protein-splitting enzyme called alpha-chymotrypsin. They modified the enzyme surface to make it soluble, then added vinyl reagents to induce the growth of molecular threads, or polymers, from the enzyme surface. A second polymerization step cross-linked silicon chains, forming a basketball-netlike structure a few nanometers thick. What result are SENs that appear in electron microscopic images as hollow enzyme-containing nanostructures about 8 nanometers across. Kim and Grate found that by using less reactive forms of vinyl they could vary the thickness of the nano-netting by half. Thick or thin, the porous netting preserves the shape of the enzyme inside yet allows its active site to interact with a substrate. SENs are also amenable to storage; they have been refrigerated for five months, losing little of their activity.

Among the uses Kim noted for SENs is the breakdown toxic waste-a single treatment could last months. Stabilized enzymes are also a prerequisite for many types of biosensors. And they may be of interest for coating surfaces, with application ranging from medicine (protecting implants from protein plaques) to shipping (keeping barnacles off hulls). PNNL is investigating several other applications in the environmental and life sciences.

PNNL is a DOE Office of Science laboratory that solves complex problems in energy, national security, the environment and life sciences by advancing the understanding of physics, chemistry, biology and computation. PNNL employs 3,800, has a $600 million annual budget, and has been managed by Ohio-based Battelle since the lab’s inception in 1965.

Bill Cannon | PNNL
Further information:
http://www.pnl.gov/news/2004/04-24.htm

More articles from Life Sciences:

nachricht Mass spectrometry sheds new light on thallium poisoning cold case
14.12.2018 | University of Maryland

nachricht Protein involved in nematode stress response identified
14.12.2018 | University of Illinois College of Agricultural, Consumer and Environmental 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: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>