Featured Research

from universities, journals, and other organizations

Brookhaven, Carnegie Scientists Report First "Morphing" Of Plant Enzyme Function

Date:
November 16, 1998
Source:
Brookhaven National Laboratory
Summary:
In a transformation worthy of Hollywood special effects, biochemists have for the first time "morphed" a plant enzyme, turning it into another enzyme with a different function, through genetic manipulation.

UPTON, NY — In a transformation worthy of Hollywood special effects,biochemists have for the first time "morphed" a plant enzyme, turning itinto another enzyme with a different function, through geneticmanipulation.

The achievement advances the prospects of "designer" plants forrenewable industrial raw materials, fuel and food. It also sheds newlight on how plant enzymes evolved to perform different functions.

The team of scientists from the U.S. Department of Energy’s BrookhavenNational Laboratory and the Carnegie Institution of Washington’sStanford, California, campus reports its accomplishment in today’s issueof Science.

"We have shown that it is possible to change an enzyme’s functiondramatically by tweaking its structure just slightly," said JohnShanklin, who co-led the research team. "Nature has been doing this foreons through mutation; our experiment shows how such changes might comeabout and what their end result is."

DOE’s Director of the Office of Science, Martha Krebs, commented, "Thisis not only a discovery of fundamental scientific significance, but itclearly demonstrates a pathway to develop an alternative,biologically-based source for many oils used in industry which currentlydepend upon petroleum for their production."

Shanklin and his colleagues worked with enzymes called desaturases andhydroxylases, taken from different species of related cruciferousplants.

Both enzymes perform important tasks. Desaturase converts plantmolecules called fatty acids from straight to bent, by turning singlechemical bonds into double ones. Hydroxylase adds hydroxy groups to thefatty acids’ structure.

These simple chemical changes can make huge differences in plant oilproperties. For example, a fatty acid molecule with two bends may besensitive to heat, while a fatty acid with an added hydroxy group isheat-resistant and performs wells as a high-temperature lubricant.

While there are hundreds of applications for existing plant oils, evenmore uses could arise from novel oils produced by plants that are givennew enzymes.

The Brookhaven-Carnegie experiments were not performed on crop plantswhose oils are harvested for industrial use, but if crop plants could besimilarly changed, farmers could produce a far more diverse set of oils.

Enzymes are made of chains of amino acids, strung together in a certainorder to create a specific architecture that determines its uniquechemical function.

By careful detective work, Shanklin and Brookhaven’s Ed Whittle, alongwith Carnegie colleagues Chris Somerville and Pierre Broun, were able toidentify which amino acids in the sequence are responsible for aparticular activity of the desaturase and hydroxylase enzymes. Bymodifying the genetic blueprint for the enzymes, they swapped severalamino acids from one enzyme for their equivalents in another enzyme.

Then, they examined the consequences by implanting the genes in a plantknown as Arabidopsis, plant scientists’ equivalent of animalgeneticists’ well-studied fruit fly. An analysis of the oil thataccumulated in the modified plant’s seeds showed that the "morphing" hadbeen successful — the desaturase had become a hydroxylase and viceversa.

The changes centered around the enzymes’ ‘active sites’ — areas thatgrab fatty acids and catalyze the chemical changes. "Picture an enzymeas an industrial punch press and its active site as the die," saidShanklin. "What we have essentially done is learned how to change thedie to make the punch press produce a different product."

This achievement, Shanklin continued, means that enzymes are more"plastic," or able to be changed, than scientists had recognized. "Notonly can this knowledge be put to work in the field of designer oils, italso has implications for the concept of patenting enzymes."

Shanklin and his colleagues have studied desaturase and other plantenzymes for several years. In 1997, a team from Brookhaven and Sweden’sKarolinska Institute were the first to alter a desaturase so that itmade fatty acids bend at a different point and created an oil withslightly different characteristics.

The research was funded by DOE’s Office of Science.

The U.S. Department of Energy’s Brookhaven National Laboratory createsand operates major facilities available to university, industrial andgovernment personnel for basic and applied research in the physical,biomedical and environmental sciences, and in selected energytechnologies. The Laboratory is operated by Brookhaven ScienceAssociates, a not-for -profit research management company, undercontract with the U.S. Department of Energy.


Story Source:

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


Cite This Page:

Brookhaven National Laboratory. "Brookhaven, Carnegie Scientists Report First "Morphing" Of Plant Enzyme Function." ScienceDaily. ScienceDaily, 16 November 1998. <www.sciencedaily.com/releases/1998/11/981116043708.htm>.
Brookhaven National Laboratory. (1998, November 16). Brookhaven, Carnegie Scientists Report First "Morphing" Of Plant Enzyme Function. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/1998/11/981116043708.htm
Brookhaven National Laboratory. "Brookhaven, Carnegie Scientists Report First "Morphing" Of Plant Enzyme Function." ScienceDaily. www.sciencedaily.com/releases/1998/11/981116043708.htm (accessed July 31, 2014).

Share This




More Health & Medicine News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Concern Grows Over Worsening Ebola Crisis

Concern Grows Over Worsening Ebola Crisis

AFP (July 30, 2014) Pan-African airline ASKY has suspended all flights to and from the capitals of Liberia and Sierra Leone amid the worsening Ebola health crisis, which has so far caused 672 deaths in Guinea, Liberia and Sierra Leone. Duration: 00:43 Video provided by AFP
Powered by NewsLook.com
At Least 20 Chikungunya Cases in New Jersey

At Least 20 Chikungunya Cases in New Jersey

AP (July 30, 2014) At least 20 New Jersey residents have tested positive for chikungunya, a mosquito-borne virus that has spread through the Caribbean. (July 30) Video provided by AP
Powered by NewsLook.com
Xtreme Eating: Your Daily Caloric Intake All On One Plate

Xtreme Eating: Your Daily Caloric Intake All On One Plate

Newsy (July 30, 2014) The Center for Science in the Public Interest released its 2014 list of single meals with whopping calorie counts. 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