Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New study pinpoints why some microbial genes are more promiscuous than others

Bacteria more likely to adopt 'loner' genes than genes that are well-connected, study finds

A new study of more than three dozen bacteria species — including the microbes responsible for pneumonia, meningitis, stomach ulcers and plague — settles a longstanding debate about why bacteria are more likely to steal some genes than others.

While most organisms get their genes from their parents just like people do, bacteria and other single-celled creatures also regularly pick up genes from more distant relatives. This ability to 'steal' snippets of DNA from other species — known as lateral gene transfer — is responsible for the rapid spread of drug resistance among disease-causing bacteria.

"By understanding why some genes are more likely to spread from one species to the next, we can better understand how new virulent bacterial strains emerge," said co-author Tal Pupko, a visiting scientist at the National Evolutionary Synthesis Center in Durham, NC.

Scientists have proposed several theories to explain why some bacterial genes are more likely to jump into other genomes. One theory, Pupko explained, is that it depends on what the gene does in the cell.

Genes involved in core functions, like converting RNA into protein, are much less likely to make the leap. "If a species already has the basic molecular machinery for transcription and translation, there's no advantage to taking in another set of genes that do the same thing," Pupko said.

Other studies suggest it's not what the gene does that matters, but how many proteins it interacts with – a network researchers have dubbed the 'interactome.' Genes involved in transcription and translation, for example, must work in concert with many partners to do their job.

To find out which factor was more important — what a gene does, or how connected it is — the researchers looked for evidence of gene transfer in more than three dozen bacteria species, including a number of pathogens known to cause illness in people.

When they compared proteins with similar degrees of connectivity, the importance of gene function disappeared. "The reason some proteins are rarely acquired is because of how connected they are, not because of their function," said co-author Uri Gophna of Tel Aviv University.

Genes whose protein products rely on many partners to do their job are less likely to work properly in a new host, Gophna said. Transferring a highly connected gene into a new host is like importing a fax machine into a remote village, he explained. "While the machine itself is potentially useful, it needs a number of additional connections to work – electricity, a phone line, a supply of paper, possibly a technician. If one of these is missing the machine becomes useless and ends up as junk."

Bacteria are more likely to adopt 'loner' genes than genes that are well-connected, the authors added. "If you think of the cell like a machine, it's much more difficult to exchange the hub of a machine than some of its accessories," Pupko said.

The scientists describe their findings in the April 2011 issue of Molecular Biology and Evolution.

Ofir Cohen of Tel Aviv University was also an author on this study.

CITATION: Cohen, O., U. Gophna, et al. (2011). "The complexity hypothesis revisited: connectivity rather than function constitutes a barrier to horizontal gene transfer." Molecular Biology and Evolution 28(4): 1481-1489. First published online December 13, 2010 doi:10.1093/molbev/msq333

The National Evolutionary Synthesis Center (NESCent) is a nonprofit science center dedicated to cross-disciplinary research in evolution. Funded by the National Science Foundation, NESCent is jointly operated by Duke University, The University of North Carolina at Chapel Hill, and North Carolina State University. For more information about research and training opportunities at NESCent, visit

Robin Ann Smith | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Make way for the mini flying machines
21.03.2018 | American Chemical Society

nachricht New 4-D printer could reshape the world we live in
21.03.2018 | American Chemical Society

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

TRAPPIST-1 planets provide clues to the nature of habitable worlds

21.03.2018 | Physics and Astronomy

The search for dark matter widens

21.03.2018 | Materials Sciences

Natural enemies reduce pesticide use

21.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>