Featured Research

from universities, journals, and other organizations

How Enzymes Work: Central Mechanism Discovered

Date:
June 20, 2007
Source:
University at Buffalo
Summary:
Chemists report the discovery of a central mechanism responsible for the action of the powerful biological catalysts known as enzymes. The research provides critical insight into why catalysis is so complex and may help pave the way for improving the design of synthetic catalysts.

University at Buffalo chemists report the discovery of a central mechanism responsible for the action of the powerful biological catalysts known as enzymes. The research provides critical insight into why catalysis is so complex and may help pave the way for improving the design of synthetic catalysts.

"The more that is known about catalysis, the better chances we have of designing active catalysts," said John P. Richard, Ph.D., professor of chemistry in the UB College of Arts and Sciences and co-author of the paper with Tina L. Amyes, Ph.D., UB adjunct associate professor of chemistry.

"Attempts to replicate evolution and design catalysts of non-biological reactions with enzyme-like activity have failed, because scientists have yet to unravel the secrets of enzyme catalysis," Richard said.

But, he said, these secrets, once revealed, have the potential to transform the chemical industry in processes ranging from soft-drink manufacturing to the production of ethanol and countless other industrial processes.

"Enzymes are the products of billions of years of cellular evolution," he said.

While attempts to design catalysts have been somewhat successful, the catalysis that results is far less efficient than that produced by reactions with enzymes.

Richard explained that protein catalysts are distinguished by their enormous molecular weights, ranging from 10,000 to greater than 1,000,000 Daltons, whereas a synthetic molecule with a weight of 1,000 would be considered large.

The recent results by Richard and Amyes provide critical insight into why effective catalysis requires such large molecules.

Catalysis starts with molecular recognition of the substrate by the catalyst, Richard explained. The so-called "catalytic" recognition is limited in man-made catalysts to several atoms that participate in the chemical reaction.

Amyes and Richard have provided compelling evidence that interactions between enzymes and non-reacting portions of the substrate are critical for large catalytic rate accelerations.

"These findings demonstrate a simple principle of catalysis that is important for many enzymes that catalyze reactions of substrates containing phosphate groups and which can be generalized to all enzymes," said Richard.

He explained that the chemistry between a catalyst and substrate occurs where groups of amino acid residues interact with the substrate.

But enzymes also have domains that interact with the non-reacting parts of the substrate, he continued. "A flexible loop on the enzyme wraps around the substrate, burying it in an environment that's favorable for catalysis," he said. "In order to bury the substrate, certain interactions are necessary that allow the loop to wrap around the substrate and that's what the phosphate groups on the substrate are doing."

The UB research demonstrates just how important this process is to catalysis. "We've shown that these interactions are critical to the process of making reactions faster," said Richard.

The critical experiment by the UB researchers was to clip the covalent bond that links the phosphate groups to the substrate.

"We have found that the interactions between phosphate groups and several enzymes are used to promote the chemistry even in the absence of a covalent linkage," said Richard. "These results have surprised many enzymologists."

To conduct the research, Richard and Amyes developed a specialized and technically difficult assay for enzyme activity that uses nuclear magnetic resonance spectroscopy to detect chemical reactions that would normally be invisible.

Richard and Amyes have applied their method during the past 10 years to a wide variety of chemical and enzymatic reactions with results published in approximately 25 papers in Biochemistry and The Journal of the American Chemical Society. Richard's work on enzymes has been supported continuously since 1987 by grants from the National Institutes of Health.

This research was published in the journal Biochemistry.


Story Source:

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


Cite This Page:

University at Buffalo. "How Enzymes Work: Central Mechanism Discovered." ScienceDaily. ScienceDaily, 20 June 2007. <www.sciencedaily.com/releases/2007/06/070619155727.htm>.
University at Buffalo. (2007, June 20). How Enzymes Work: Central Mechanism Discovered. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2007/06/070619155727.htm
University at Buffalo. "How Enzymes Work: Central Mechanism Discovered." ScienceDaily. www.sciencedaily.com/releases/2007/06/070619155727.htm (accessed September 22, 2014).

Share This



More Plants & Animals News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: San Diego Zoo Welcomes Cheetah Cubs

Raw: San Diego Zoo Welcomes Cheetah Cubs

AP (Sep. 20, 2014) The San Diego Zoo has welcomed two Cheetah cubs to its Safari Park. The nearly three-week-old female cubs are being hand fed and are receiving around the clock care. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
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