A designer enzyme for alternative energy

June 21, 2013 by Mona S. Rowe
Ribbon diagram showing introduction of histadine and tyrosine residues into myoglobin, resulting in enzymes that reduce oxygen (O2)to water (H2O) with more than 1,000 turnovers and minimal release of reactive oxygen species.

(Phys.org) —Imagine pulling energy out of thin air. Yi Lu and his colleagues are on that path, in a quest to find alternatives to fossil fuels. The team has designed an enzyme that can harvest the energy of atmospheric oxygen with high efficiency and long life. Their work is a big step in custom designing artificial enzymes for potential applications in alternative energy.

"Oxygen in air is abundant and cheap. Yet converting it to useful energy requires catalysts with and stability," said Lu, a professor at the University of Illinois. He explained that nature's catalysts are among the most efficient, certainly better than most fuel-cell catalysts of today. A typical "native" catalyst is the enzyme heme carbon oxidase, or HCO. But HCOs are too big, too expensive and too unstable for practical applications.

"We have designed an enzyme that is much smaller, cheaper and more stable than the native enzymes," said Lu.

In brief, they introduced one tyrosine and two histidine residues into , which yielded an enzyme that catalyzed the reduction of oxygen to water with minimal release of reactive oxygen species and more than 1,000 turnovers – the number of times an enzyme can catalyze the same reaction over and over. are incomplete intermediates for the oxygen reduction; they not only decrease the efficiency of the energy-conversion reaction, but also damage fuel-cell components.

According to Lu, designing enzymes, especially ones such as theirs that contain , is a real challenge. Most designed enzymes have relatively low turnovers and efficiency, making them difficult to use for applications. The researchers demonstrated the feasibility of designing enzymes with both high turnovers and efficiency.

From initial design of the enzymes to final confirmation of the design, obtaining high-resolution crystal structures is essential at every stage of this project, said Lu. That work has been done with Photon Sciences (PS) biologist Howard Robinson at Brookhaven National Laboratory's National Synchrotron Light Source (NSLS). Looking ahead, the research will continue at NSLS-II, expected to start commissioning at Brookhaven in 2014. Said Lu, "The new facility will offer even better capability to obtain crystal structures. It will also allow simultaneous study of our designed enzymes by both crystallography and single-crystal spectroscopy." The team has already started working toward that direction with Allen Orville, another PS biologist.

This current work on enzyme design was published in the journal Angewandte Chemie International Edition.

Explore further: Researchers First to 'See' Reactive Oxygen Species in Vital Enzyme

Related Stories

Researchers harness nature to produce the fuel of the future

January 30, 2013

Hydrogen has tremendous potential as an eco-friendly fuel, but it is expensive to produce. Now researchers at Princeton University and Rutgers University have moved a step closer to harnessing nature to produce hydrogen for ...

A cure for the common hangover?

February 18, 2013

(Phys.org)—In a discovery that could derail the popular "Hangover" movie franchise, a team of researchers led by UCLA engineers has identified a method for speeding up the body's reaction to the consumption of alcohol.

Charge your mobile phone with formic acid?

May 27, 2013

(Phys.org) —Surprisingly the answer is yes. With the technology of today it is possible to use environmental friendly formic acid in fuel cell powering your mobile phone or laptop. Physicist Florian Nitze, Umeå University, ...

High-efficiency zinc-air battery developed

May 29, 2013

Stanford University scientists have developed an advanced zinc-air battery with higher catalytic activity and durability than similar batteries made with costly platinum and iridium catalysts. The results, published in the ...

Recommended for you

New method developed for producing some metals

August 25, 2016

The MIT researchers were trying to develop a new battery, but it didn't work out that way. Instead, thanks to an unexpected finding in their lab tests, what they discovered was a whole new way of producing the metal antimony—and ...

Force triggers gene expression by stretching chromatin

August 26, 2016

How genes in our DNA are expressed into traits within a cell is a complicated mystery with many players, the main suspects being chemical. However, a new study by University of Illinois researchers and collaborators in China ...

Isolation of Fe(IV) decamethylferrocene salts

August 29, 2016

(Phys.org)—Ferrocene is the model compound that students often learn when they are introduced to organometallic chemistry. It has an iron center that is coordinated to the π electrons in two cyclopentadienyl rings. (C5H5- ...

New electrical energy storage material shows its power

August 24, 2016

A powerful new material developed by Northwestern University chemist William Dichtel and his research team could one day speed up the charging process of electric cars and help increase their driving range.


Adjust slider to filter visible comments by rank

Display comments: newest first

3 / 5 (2) Jun 21, 2013
This article appears extermely confused.

Reducing oxygen to water is not "harvesting the energy of oxygen in the atmosphere", it's simply combusting hydrogen fuel.
1 / 5 (1) Jun 21, 2013
@Eikka, Thanks for clarifying this. The article does not describe the full chemical reaction that these catalysts are enabling. It looks like this article is a press release that was prepared by a non-scientist in the PR department.
1 / 5 (4) Jun 21, 2013
I agree with Eikka. Turning oxygen in the air (where does the hydrogen come from?) into water produces water, not energy. Where is the energy produced? One also has to question the wisdom of a technology that makes the air unfit for breathing.
1 / 5 (1) Jun 21, 2013
Yes, it is not stated what form(s) the energy released from this reaction consists of.
1 / 5 (2) Jun 21, 2013
I call Bullshit. As pointed out by others, H2O is not energy nor energy storage. NTM where is all the 'free' H coming from. But even if it was as (poorly) claimed, is extracting O2 from the atmosphere actually a good idea when oceanic plankton and tropical rain forests are being decimated day in a day out. Atmospheric O2 levels are declining globally as it is. Dumb FKN monkeys.
1 / 5 (4) Jun 22, 2013
oceanic plankton and tropical rain forests being decimated day in a (sic) day out

First: Don't Panic (in large friendly letters, on the front).

Second: Only meteor impacts, million year CMEs, GRBs, nearby Supernovae, and large volcanic events cause enough damage to actually hurt anything over the long term (otherwise we'd have never evolved)

Third: Don't Panic (in large friendly letters on the back).
2 / 5 (4) Jun 22, 2013
Atmospheric O2 levels are declining globally as it is.

Cite, please.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.