Featured Research

from universities, journals, and other organizations

How Enzyme Works: A Molecular Switch Turns On The Flame In 'Nature's Blowtorch'

Date:
June 2, 2008
Source:
Brandeis University
Summary:
Uncontrolled reaction of organic compounds with oxygen is easy: we call it fire. But nature often needs to do oxidations very specifically, adding oxygen to a particular carbon atom in a complicated molecule without disturbing anything else. Usually, this job falls to an enzyme called cytochrome P450.

Uncontrolled reaction of organic compounds with oxygen is easy: we call it fire. But nature often needs to do oxidations very specifically, adding oxygen to a particular carbon atom in a complicated molecule without disturbing anything else. Usually, this job falls to an enzyme called cytochrome P450. Because cytochrome P450 can catalyze molecular oxidations with pinpoint accuracy, it has been called "nature's blowtorch," and its job is analogous to that of a welder doing a tricky repair in a highly flammable wooden house. It needs to do the repair without burning itself or the house.

Brandeis University researchers have been trying to understand the details of how P450 does this job so efficiently; that is, "burning" the right places in the target molecule (substrate) while not "burning down the house."

In new research online in the Cell Press journal Structure, chemistry graduate student Bo OuYang, along with fellow grad student Marina Dang and advisors Thomas and Susan Pochapsky, describe a new insight into how P450 works. The researchers discovered that the protein chain in P450 can change its structure by a 180 degree rotation around a single peptide bond. In one orientation, both oxygen and the molecule to be oxidized (substrate) can get in and out of the P450 active site, but the oxygen is not "activated," that is, it is not in a state to react with the substrate (or anything else, for that matter).

In the other orientation, however, the substrate is held tightly in the correct orientation for the oxidation, and the oxygen can be activated to do "the burn." The activated form of the molecule is generated by binding a helper protein, called Pdx, to the P450. This binding drives the reorientation around the peptide bond, and moves the P450 from the form in which substrate binds to the active form. After the reaction is finished, the Pdx falls off, the P450 moves back to the unactivated state, and the oxidized products are free to leave.

After another substrate molecule and oxygen move into the active site, the cycle can repeat. The reorientation of a single peptide bond, an event called an "isomerization," thus acts as a molecular switch, moving the P450 between safe and active forms while protecting the P450 and its environment from accidental oxidative damage.

Much of the experimental work for this discovery was done using the NIH-funded 800 MHz NMR spectrometer housed in the Landsman Research Facility at Brandeis University.


Story Source:

The above story is based on materials provided by Brandeis University. Note: Materials may be edited for content and length.


Cite This Page:

Brandeis University. "How Enzyme Works: A Molecular Switch Turns On The Flame In 'Nature's Blowtorch'." ScienceDaily. ScienceDaily, 2 June 2008. <www.sciencedaily.com/releases/2008/05/080529170518.htm>.
Brandeis University. (2008, June 2). How Enzyme Works: A Molecular Switch Turns On The Flame In 'Nature's Blowtorch'. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2008/05/080529170518.htm
Brandeis University. "How Enzyme Works: A Molecular Switch Turns On The Flame In 'Nature's Blowtorch'." ScienceDaily. www.sciencedaily.com/releases/2008/05/080529170518.htm (accessed October 21, 2014).

Share This



More Matter & Energy News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Massive Air Bag Recall Affects More Than 4.5 Million Vehicles

Massive Air Bag Recall Affects More Than 4.5 Million Vehicles

Reuters - US Online Video (Oct. 21, 2014) Major automakers are recalling millions of vehicles due to potentially defective front passenger air bag inflators that can rupture and spray metal shrapnel. Linda So reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins