Unique chemistry in hydrogen catalysts

October 24, 2013

Making hydrogen easily and cheaply is a dream goal for clean, sustainable energy. Bacteria have been doing exactly that for billions of years, and now chemists at the University of California, Davis, and Stanford University are revealing how they do it, and perhaps opening ways to imitate them.

A study published Oct. 25 in the journal Science describes a key step in assembling the hydrogen-generating catalyst.

"It's pretty interesting that bacteria can do this," said David Britt, professor of chemistry at UC Davis and co-author on the paper. "We want to know how nature builds these catalysts—from a chemist's perspective, these are really strange things."

The bacterial catalysts are based on precisely organized clusters of iron and sulfur atoms, with side groups of cyanide and . Those molecules are highly toxic unless properly controlled, Britt noted.

The cyanide and carbon monoxide groups were known to come from the , Britt said. Jon Kuchenreuther, a postdoctoral researcher in Britt's laboratory, used a technique called to study the structure of the intermediate steps.

They found a series of chemical reactions involving a type of highly reactive called a radical SAM enzyme. The tyrosine is attached to a cluster of four iron atoms and four , then cut loose leaving the cyanide and carbon monoxide groups behind.

"People think of radicals as dangerous, but this enzyme directs the radical chemistry, along with the production of normally poisonous CO and CN, along safe and productive pathways," Britt said.

Kuchenreuther, Britt and colleagues also used another technique, Fourier Transform Infrared to study how the iron-cyanide-carbon monoxide complex is formed. That work will be published separately.

"Together, these results show how to make this interesting two-cluster enzyme," Britt said. "This is unique, new chemistry."

Explore further: Cobalt catalysts for simple water splitting

More information: "A Radical Intermediate in Tyrosine Scission to the CO and CN Ligands of [FeFe] Hydrogenase" Science, 2013.

Related Stories

Cobalt catalysts for simple water splitting

May 7, 2010

(PhysOrg.com) -- Researchers from UC Davis and the Massachusetts Institute of Technology are studying how a simple cobalt catalyst can split water molecules. Such inexpensive catalysts could one day be used to convert sunlight ...

New method for producing clean hydrogen

May 21, 2013

Duke University engineers have developed a novel method for producing clean hydrogen, which could prove essential to weaning society off of fossil fuels and their environmental implications.

The dance of the atoms

June 10, 2013

(Phys.org) —Catalysts can stop working when atoms on the surface start moving. At the Vienna University of Technology, this dance of the atoms could now be observed and explained.

New small-molecule catalyst does the work of many enzymes

October 3, 2013

Researchers report that they have created a man-made catalyst that is an "enzyme mimic." Unlike most enzymes, which act on a single target, the new catalyst can alter the chemical profiles of numerous types of small molecules. ...

Cheap metals can be used to make products from petroleum

October 21, 2013

The ancient alchemists sought to transform base metals, like lead, into precious gold. Now a new process developed at the University of Illinois at Chicago suggests that base metals may be worth more than their weight in ...

Recommended for you

New polymer creates safer fuels

October 1, 2015

Before embarking on a transcontinental journey, jet airplanes fill up with tens of thousands of gallons of fuel. In the event of a crash, such large quantities of fuel increase the severity of an explosion upon impact. Researchers ...

Researchers print inside gels to create unique shapes

September 30, 2015

(Phys.org)—A team of researchers at the University of Florida has taken the technique of printing objects inside of a gel a step further by using a highly shear-rate sensitive gel. In their paper published in the journal ...

How a molecular motor untangles protein

October 1, 2015

A marvelous molecular motor that untangles protein in bacteria may sound interesting, yet perhaps not so important. Until you consider the hallmarks of several neurodegenerative diseases—Huntington's disease has tangled ...

Anti-aging treatment for smart windows

October 1, 2015

Electrochromic windows, so-called 'smart windows', share a well-known problem with rechargeable batteries – their limited lifespan. Researchers at Uppsala University have now worked out an entirely new way to rejuvenate ...


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.