Navigation Links
Heat helped hasten life's beginnings
Date:12/2/2010

CHAPEL HILL, N.C. -- There has been controversy about whether life originated in a hot or cold environment, and about whether enough time has elapsed for life to have evolved to its present complexity.

But new research at the University of North Carolina at Chapel Hill investigating the effect of temperature on extremely slow chemical reactions suggests that the time required for evolution on a warm earth is shorter than critics might expect.

The findings are published in the Dec. 1, 2010, online early edition of the Proceedings of the National Academy of Sciences.

Enzymes, proteins that jump-start chemical reactions, are essential to life within cells of the human body and throughout nature. These molecules have gradually evolved to become more sophisticated and specific, said lead investigator Richard Wolfenden, PhD, Alumni Distinguished Professor of biochemistry and biophysics at UNC School of Medicine.

To appreciate how powerful modern enzymes are, and the process of how they evolved, scientists need to know how quickly reactions occur in their absence.

Wolfenden's group measured the speed of chemical reactions, estimating that some of them take more than 2 billion years without an enzyme.

In the process of measuring slow reaction rates, "it gradually dawned on us that the slowest reactions are also the most temperature-dependent," Wolfenden said.

In general, the amount of influence temperature has on reaction speeds varies drastically, the group found. In one slow reaction, for instance, raising the temperature from 25 to 100 degrees Celsius increases the rate 10 million fold. "That is a shocker," Wolfenden said. "That's what's going to surprise people most, as it did me."

That is surprising, Wolfenden said, because a textbook rule in chemistry for more than a century has been that the influence of temperature is modest. In particular, a doubling in reaction rate occurs when the temperature rises 10 degree Celsius, according to experiments done in 1866.

High temperatures were probably a crucial influence on reaction rates when life began forming in hot springs and submarine vents, Wolfenden said. Later, the cooling of the earth provided selective pressure for primitive enzymes to evolve and become more sophisticated, the Wolfenden's group hypothesizes.

Using two different reaction catalysts which are not protein enzymes but that may have resembled early precursors to enzymes the group put the hypothesis to the test. The catalyzed reactions are indeed far less sensitive to temperature, compared with reactions that are accelerated by catalysts. The results are consistent with our hypothesis, Wolfenden said.

Wolfenden's group plans to test the hypothesis using other catalysts. In the meantime, these findings are likely to influence how scientists think of the first primitive forms of life on earth, and may affect how researchers design and enhance the power of artificial catalysts, he added.


'/>"/>

Contact: Les Lang
llang@med.unc.edu
919-966-9366
University of North Carolina School of Medicine
Source:Eurekalert

Related biology news :

1. New World post-pandemic reforestation helped start Little Ice Age, say Stanford scientists
2. Snakes and how they helped our big brains evolve
3. Adapting to darkness: How behavioral and genetic changes helped cavefish survive extreme environment
4. Global warming predicted to hasten carbon release from peat bogs
5. Stress may hasten the growth of melanoma tumors
6. Biofuels could hasten climate change
7. UCI receives prestigious federal research award to hasten medical advances
8. NIH Transformative Research Project Awards hasten innovation
9. M.I.N.D. Institute researchers call for fragile X testing throughout the lifespan
10. Modern lifestyle prevents tooth decay
11. Late motherhood boosts family lifespan
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/27/2017)... ROCKVILLE CENTRE, N.Y. , March 27, 2017 ... by Healthcare Information and Management Systems Society (HIMSS) ... Analytics Outpatient EMR Adoption Model sm . In ... top 12% of U.S. hospitals using an electronic ... recognized CHS for its high level of EMR ...
(Date:3/23/2017)... 23, 2017 The report "Gesture Recognition and Touchless Sensing ... Geography - Global Forecast to 2022", published by MarketsandMarkets, the market is expected ... 29.63% between 2017 and 2022. Continue Reading ... ... ...
(Date:3/22/2017)... March 21, 2017 Optimove , ... by retailers such as 1-800-Flowers and AdoreMe, today ... Recommendations and Replenishment. Using Optimove,s machine learning algorithms, ... product and replenishment recommendations to their customers based ... predictions of customer intent drawn from a complex ...
Breaking Biology News(10 mins):
(Date:8/16/2017)... , Aug. 16, 2017  Kingfisher Talent, the ... development, and Virdis Group, global executive search specialists in the ... enables clients to leverage the expertise and reach of both ... here in the Boston biotech hub, ... leadership talent throughout the US, Canada ...
(Date:8/15/2017)... , ... August 15, 2017 , ... ... biosensors that accelerate pharmaceutical and biotherapeutics development, announces the launch of the new ... steps needed to gain kinetic binding data for a wide range of molecules, ...
(Date:8/15/2017)... , ... August 15, 2017 , ... ... family of 6” modular downlights designed to stay tightly sealed and perform efficiently ... where damp and wet location listings just aren't enough, such as: hospitals; behavioral ...
(Date:8/15/2017)... ... 15, 2017 , ... JULABO USA introduces its new website ... makes it easy to navigate through the site whether you’re in the office, ... information, educational industry content and visit the company’s social media accounts, all on ...
Breaking Biology Technology: