Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Evolution mystery: Spider venom and bacteria share same toxin

02.02.2006


It’s a case of evolutionary detective work. Biology researchers at Lewis & Clark College and the University of Arizona have found evidence for an ancient transfer of a toxin between ancestors of two very dissimilar organisms--spiders and a bacterium. But the mystery remains as how the toxin passed between the two organisms. Their research is published this month in the journal Bioinformatics, 22(3): 264-268, in an article titled "Lateral gene transfer of a dermonecrotic toxin between spiders and bacteria."


"We are piecing together an historical puzzle with evidence from living descendants of an ancient ancestor," said Greta Binford, assistant professor of biology at Lewis & Clark. Her coresearcher on the project is Matthew Cordes, assistant professor of biochemistry and molecular biophysics at the University of Arizona. The toxin is uniquely found in the venom cocktail of brown or violin spiders, including the brown recluse, and in some Corynebacteria. The toxin from the spider’s venom can kill flesh at the bite site; the bacterium causes various illnesses in farm animals.

"Our research was inspired by the fact that we have a group of spiders with a unique toxin, and that toxin also happens to exist outside the animal kingdom in this particular bacterium," she added. "A pattern like this raises the possibility of lateral gene transfer as a explanation." Lateral gene transfer refers to the movement of genes between the genomes of unrelated organisms. This contrasts with vertical transfer of genes from parent to offspring.

Cordes and Binford found a common structural motif at the end of both toxic proteins that is not found in any other proteins. Evidence for common ancestry (homology) of the toxins had previously been noted, but this uniquely shared structural bit is best explained by these toxins being more closely related to each other than they are to any other known protein.



"That one structural detail--which resembles a plug or cork at the end of a barrel-shaped enzyme--is evidence that the spider and bacterium share a relatively recent common ancestor," Cordes said. "Aside from being an example of lateral transfer between very distantly related organisms, this study is an unusual example of using structural motifs in proteins to answer questions about common ancestry when gene sequences are too different to be clear about these relationships."

"We’re still left with the question of whether this venom enzyme hopped species from the spider to the bacteria, or the other way around. Either way, the presence of this medically-relevant toxin in one of these groups of organisms is likely the result of transfer from the other lineage," Binford said. "Understanding the importance of this structural motif in the toxic activity may help with developing treatments that minimize the effects of bites of brown recluse and their relatives. If this motif is central to protein function, treatments designed for the spider bites may also work for treating problems caused by the corynebacterial toxin," she added.

Tania Thompson | EurekAlert!
Further information:
http://www.lclark.edu

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>