Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Viruses Hijack Deep-Sea Bacteria at Hydrothermal Vents

02.05.2014

More than a mile beneath the ocean’s surface, as dark clouds of mineral-rich water billow from seafloor hot springs called hydrothermal vents, unseen armies of viruses and bacteria wage war.

Like pirates boarding a treasure-laden ship, the viruses infect bacterial cells to get the loot: tiny globules of elemental sulfur stored inside the bacterial cells.


Image courtesy of MARUM, University of Bremen and NOAA-Pacific Marine Environmental Laboratory.

Black smoke from the top of a "chimney" in the Lau Basin in the western Pacific Ocean. Water samples collected by an unmanned submarine revealed how viruses hijack deep-sea bacteria at hydrothermal vents.

Instead of absconding with their prize, the viruses force the bacteria to burn the valuable sulfur reserves, then use the unleashed energy to replicate, eventually filling the bacterial cells to the bursting point.

“Our findings suggest that viruses in the dark oceans indirectly access vast energy sources in the form of elemental sulfur,” said University of Michigan marine microbiologist and oceanographer Gregory J. Dick, whose team collected DNA from deep-sea microbes in seawater samples from hydrothermal vent sites in the western Pacific Ocean and the Gulf of California.

The study identifies viruses as key players in the thriving ecosystems – which include exotic 6-foot tube worms, giant clams and mussels, as well as shrimp – huddled around deep-sea hydrothermal vents.

In addition, they hint that the viruses act as agents of evolution in chemosynthetic systems by swapping genes with the bacteria, Dick said. “We suggest that the viruses serve as a reservoir of genetic diversity that helps shape bacterial evolution,” he said.

A paper summarizing the findings is scheduled for online publication May 1 in Science. The first author is Karthik Anantharaman, a doctoral student in Dick’s lab at the Department of Earth and Environmental Sciences.

Similar microbial interactions have been observed in shallow ocean waters between photosynthetic bacteria and the viruses that prey on them. But this is the first time such a relationship has been seen in a chemosynthetic system, one in which the microbes rely solely on inorganic compounds, rather than sunshine, as their energy source.

Dick and his colleagues collected water samples during trips to the Eastern Lau Spreading Center in the Western Pacific and the Guaymas Basin in the Gulf of California. An unmanned submarine from the Woods Hole Oceanographic Institution captured the samples, at a depth of more than 6,000 feet, near “black smokers” spewing mineral-rich seawater at temperatures surpassing 500 degrees Fahrenheit.

Back in the laboratory, the researchers reconstructed near-complete viral and bacterial genomes from the DNA snippets retrieved at six hydrothermal vent plumes. In addition to the common sulfur-consuming bacterium SUP05, they found genes from five previously unknown viruses.

The genetic data suggest that the viruses prey on SUP05. That’s not too surprising, since viruses are the most abundant biological entities in the oceans and are a pervasive cause of mortality among marine microorganisms.

The real surprise is that the viral DNA contains genes closely related to SUP05 genes used to extract energy from sulfur compounds.

When combined with results from previous studies, this finding suggests that the viruses force SUP05 bacteria to use viral SUP05-like genes to help process stored globules of elemental sulfur. The SUP05-like viral genes are called auxiliary metabolic genes.

“We hypothesize that the viruses enhance bacterial consumption of this elemental sulfur, to the benefit of the viruses,” said co-author Melissa Duhaime, an assistant research scientist in the U-M Department of Ecology and Evolutionary Biology. The revved-up metabolic reactions may release energy that the viruses then use to replicate and spread.

“We suspect that these viruses are essentially hijacking bacterial cells and getting them to consume elemental sulfur so the viruses can propagate themselves,” Anantharaman said.

But how did SUP05-like genes end up in these viruses? The researchers can’t say for sure, but presumably the viruses snatched genes from SUP05 during some ancient microbial interaction.

“There seems to have been an exchange of genes, which implicates the viruses as an agent of evolution. That’s interesting from an evolutionary biology standpoint,” Dick said.

The new microbial findings will help researchers understand how marine biogeochemical cycles, including the sulfur cycle, will respond to global environmental changes such as the ongoing expansion of dead zones. SUP05 bacteria, which may generate the greenhouse gas nitrous oxide, will likely expand their range as oxygen-starved zones continue to grow in the oceans.

In addition to Anantharaman, Dick and Duhaime, authors of the Science paper are John A. Breir of the Woods Hole Oceanographic Institution, Kathleen Wendt of the University of Minnesota and Brandy M. Toner of the University of Minnesota.

The project was funded in part by the Gordon and Betty Moore Foundation through grants GBMF2609 and GBMF2764; the National Science Foundation through grants OCE-1038006, OCE-1038055, OCE-1037991 and OCE-1029242; and the U-M Rackham Graduate School Faculty Research Fellowship Program.

“Viruses play a cardinal role in biogeochemical processes in the ocean’s shallow and mid-to-deeper waters,” said David Garrison, program director in the National Science Foundation’s Division of Ocean Sciences, which funded the research. “This study suggests that viruses may have a similar importance in deep-sea thermal vent environments.”

Jim Erickson | newswise
Further information:
http://www.umich.edu

Further reports about: DNA Hydrothermal Oceanographic bacteria bacterial genes grants metabolic microbial oceans sulfur viruses

More articles from Earth Sciences:

nachricht Researchers find higher than expected carbon emissions from inland waterways
25.05.2016 | Washington State University

nachricht Rutgers scientists help create world's largest coral gene database
24.05.2016 | Rutgers University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Worldwide Success of Tyrolean Wastewater Treatment Technology

A biological and energy-efficient process, developed and patented by the University of Innsbruck, converts nitrogen compounds in wastewater treatment facilities into harmless atmospheric nitrogen gas. This innovative technology is now being refined and marketed jointly with the United States’ DC Water and Sewer Authority (DC Water). The largest DEMON®-system in a wastewater treatment plant is currently being built in Washington, DC.

The DEMON®-system was developed and patented by the University of Innsbruck 11 years ago. Today this successful technology has been implemented in about 70...

Im Focus: Computational high-throughput screening finds hard magnets containing less rare earth elements

Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.

The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...

Im Focus: Atomic precision: technologies for the next-but-one generation of microchips

In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.

In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...

Im Focus: Researchers demonstrate size quantization of Dirac fermions in graphene

Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices

Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.

Im Focus: Graphene: A quantum of current

When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene

In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking 4.0: International Laser Technology Congress AKL’16 Shows New Ways of Cooperations

24.05.2016 | Event News

Challenges of rural labor markets

20.05.2016 | Event News

International expert meeting “Health Business Connect” in France

19.05.2016 | Event News

 
Latest News

11 million Euros for research into magnetic field sensors for medical diagnostics

27.05.2016 | Awards Funding

Fungi – a promising source of chemical diversity

27.05.2016 | Life Sciences

New Model of T Cell Activation

27.05.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>