Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Light-sensing protein illuminates sun-loving ocean bacteria

19.07.2005


About 13% of bacteria near the ocean’s surface contain proteorhodopsin, a membrane protein able to harness sunlight’s energy, according to a new study by Oded Beja and colleagues in the open-access journal PLoS Biology. Given the dearth of nutrients in their environment, these oligotrophic bacteria must generate their energy from a variety of sources. The study reveals that proteorhodopsin is uniquely suited to capturing the high-radiation sunlight that illuminates the sea. Through the use of meta-genomic analysis, the authors also observed great diversity among proteorhodopsin genes.


Ocean bacteria with the light-sensitive proteorhodopsin enzyme live several meters above this coral reef. (Photo: Boaz Harel)



Estimating the average size of the bacterial genome led Beja and colleagues to the conclusion that about 13% of ocean bacteria encode proteorhodopsin. "This is a big chunk of the population that is harvesting light in a different way than photosynthesis," says Beja. He added that his study "is the first to report fast photocycles with the so-called blue proteorhodopsins. This means both blue and green proteorhodopsins can act as proton pumps" to harvest energy because they contain proteorhodopsin. The authors also found some evidence suggesting that many of the bacteria with proteorhodopsin might be able to metabolize sulfur, a common energy source for deep-sea life. The marine bacteria might additionally be able to manufacture retinal, a molecule typically associated with vision.

The authors skimmed their bacteria samples from the top, or photic layer, of the Mediterranean and Red Seas. Since these bacteria can’t survive typical lab conditions, the scientists inserted large segments of collected ocean bacterial DNA into host bacteria to create an amplified collection of the genome known as a large-insert bacterial artificial chromosome (BAC) library. To detect the gene segments of interest, the scientists used "specially designed PCR primers that can detect almost all proteorhodopsins reported today," Beja explains.


Many other organisms use proteins resembling proteorhodopsin for different functions. Humans, for instance, use rhodopsin to sense light in the eyeball. The presence of rhodopsin-like proteins in a wide range of life may eventually provide hints to the protein’s evolutionary age. That this large class of transmembrane proteins was so well-conserved over a long evolutionary time scale provides evidence for complex ancient proteins. The new study also raises the question of whether bacteria use proteorhodopsin solely for energy transduction or also for sensory input as humans use rhodopsin.

Paul Ocampo | EurekAlert!
Further information:
http://www.plosbiology.org
http://www.plos.org

More articles from Life Sciences:

nachricht Not of Divided Mind
19.01.2017 | Hertie-Institut für klinische Hirnforschung (HIH)

nachricht CRISPR meets single-cell sequencing in new screening method
19.01.2017 | CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>