Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Light-sensing protein illuminates sun-loving ocean bacteria


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:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>