Featured Research

from universities, journals, and other organizations

'Two In One' Enzyme: Unusually Flexible

Date:
October 16, 2008
Source:
Ruhr-Universitaet-Bochum
Summary:
Scientists have solved the structure of an unusually flexible enzyme in a virus that infects marine bacteria.

3D structural model of the phycoerythrobilin synthase (PebS) with the attached biliverdin substrate (green).
Credit: Image courtesy of Ruhr-Universitaet-Bochum

Scientists from the Ruhr-University Bochum (RUB) have solved the structure of an unusually flexible enzyme in a virus that infects marine bacteria.

Related Articles


The virus, which infects the marine cyanobacterium Prochlorococcus, can produce specific pigments more effectively than its host can. It requires only one enzyme, in contrast to the host Prochlorococcus, which needs two enzymes. The virus makes use of phycoerythrobilin synthase, a “two in one” enzyme.

As part of his dissertation, Thorben Dammeyer, a member of the research team under the supervision of Prof. Nicole Frankenberg-Dinkel (Physiology of Microorganisms) and Assistant Professor Dr. Eckhard Hofmann (X-ray diffraction analysis of proteins), solved the 3D structure of the enzyme. An unexpected flexibility was discovered, allowing sections of the protein to assume different positions – an unusual property for proteins in combination with their substrate.

The scientists have documented their results, honored as “Paper of the Week,” in the current issue of the Journal of Biological Chemistry.

Pigments are produced in two steps

The so-called P-SSM2 virus with the “two in one” enzyme infects the cyanobacterium Prochlorococcus, a cyanobacterium found in extremely large numbers in the worlds oceans. The virus does however differ in that - in contrast to its cyanobacterial relatives - it does not harvest light for photosynthesis via red and blue pigments, but with chlorophyll, as is the case with higher plants. Nevertheless Prochlorococcus contains all the genetic information for the entire machinery required to produce these pigments. This takes place in two steps with two different enzymes as catalysts.

Green turns red in one step

Nicole Frankenberg-Dinkel stated that “we have discovered the genetic blueprint for an enzyme within the virus. This enzyme is capable of producing the red pigment more effectively than its host, which has convinced us that the pigment cannot be unimportant for Prochlorococcus, even if it is not required for light trapping. On the other hand, we obviously wanted to know how this enzyme can combine two functions.”

The scientists used X-ray diffraction analysis to determine the 3D structure of the enzyme at atomic resolution both alone and in complex with its natural substrate, the green biliverdin IXa. This molecule was found in the binding pocket of the protein, where the conversion into a red pigment takes place.

Prof. Frankenberg-Dinkel explained that the scientists were able to observe how different parts of the enzyme around the binding pocket are capable of assuming different positions. “This property might not be unusual for proteins in solution, but is extremely rarely found in protein crystals.” The structural variations observed supplied the scientists with the first indications of the movements of the enzyme during catalysis.

Next step: tracking the evolution

The next stage of research will consist of studies of targeted and randomly genetically altered forms of the unusually flexible protein. Using this system, the scientists want to observe the in vitro evolution of this specific enzyme. Nicole Frankenberg-Dinkel’s and Eckhard Hofmann’s research teams are funded by the Collaborative Research Centre 480 “Molecular Biology of Complex Functions in Botanical Systems.”


Story Source:

The above story is based on materials provided by Ruhr-Universitaet-Bochum. Note: Materials may be edited for content and length.


Journal Reference:

  1. Dammeyer, T., Hofmann, E. & Frankenberg-Dinkel, N. Phycoerythrobilin synthase (PebS) of a marine virus: Crystal structure of the biliverdin-complex and the substrate free form. J.Biol. Chem., 2008; 283: 27547-27554

Cite This Page:

Ruhr-Universitaet-Bochum. "'Two In One' Enzyme: Unusually Flexible." ScienceDaily. ScienceDaily, 16 October 2008. <www.sciencedaily.com/releases/2008/10/081006093026.htm>.
Ruhr-Universitaet-Bochum. (2008, October 16). 'Two In One' Enzyme: Unusually Flexible. ScienceDaily. Retrieved April 21, 2015 from www.sciencedaily.com/releases/2008/10/081006093026.htm
Ruhr-Universitaet-Bochum. "'Two In One' Enzyme: Unusually Flexible." ScienceDaily. www.sciencedaily.com/releases/2008/10/081006093026.htm (accessed April 21, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Tuesday, April 21, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Humanoid Robot Can Recognise and Interact With People

Humanoid Robot Can Recognise and Interact With People

Reuters - Innovations Video Online (Apr. 20, 2015) An ultra-realistic humanoid robot called &apos;Han&apos; recognises and interprets people&apos;s facial expressions and can even hold simple conversations. Developers Hanson Robotics hope androids like Han could have uses in hospitality and health care industries where face-to-face communication is vital. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Drones and Health Apps at Santiago's "Robotics Day"

Drones and Health Apps at Santiago's "Robotics Day"

AFP (Apr. 20, 2015) Latin American robotics experts gather in Santiago, Chile for "Robotics Day". Video provided by AFP
Powered by NewsLook.com
Japan Humanoid Robot Receives Customers at Department Store

Japan Humanoid Robot Receives Customers at Department Store

AFP (Apr. 20, 2015) She can smile, she can sing and she can give you guidance at one of the most upscale department stores in Tokyo...a female-looking humanoid makes her debut as a receptionist Video provided by AFP
Powered by NewsLook.com
Pee-Power Toilet to Light Up Disaster Zones

Pee-Power Toilet to Light Up Disaster Zones

Reuters - Innovations Video Online (Apr. 20, 2015) Students and staff are being asked to use a prototype urinal to &apos;donate&apos; urine to fuel microbial fuel cell (MFC) stacks that generate electricity to power lighting. The developers hope the pee-power technology will light toilet cubicles in refugee camps, where women are often at risk of assault in poorly lit sanitation areas. Matthew Stock 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