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 September 16, 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 September 16, 2014).

Share This



More Matter & Energy News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Manufacturer Prints 3-D Car In Record Time

Manufacturer Prints 3-D Car In Record Time

Newsy (Sep. 15, 2014) — Automobile manufacturer Local Motors created a drivable electric car using a 3-D printer. Printing the body only took 44 hours. Video provided by Newsy
Powered by NewsLook.com
Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Refurbished New York Subway Tunnel Unveiled After Sandy Damage

Reuters - US Online Video (Sep. 15, 2014) — New York officials unveil subway tunnels that were refurbished after Superstorm Sandy. Nathan Frandino reports. Video provided by Reuters
Powered by NewsLook.com
Frustration As Drone Industry Outpaces Regulation In U.S.

Frustration As Drone Industry Outpaces Regulation In U.S.

Newsy (Sep. 14, 2014) — U.S. firms worry they’re falling behind in the marketplace as the FAA considers how to regulate commercial drones. Video provided by Newsy
Powered by NewsLook.com
Smart Gun Innovators Fear Backlash From Gun Rights Advocates

Smart Gun Innovators Fear Backlash From Gun Rights Advocates

Newsy (Sep. 14, 2014) — Winners of a contest for smart gun design are asking not to be named after others in the industry received threats for marketing similar products. Video provided by Newsy
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:
from the past week

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