News http://www.fourmentinguilbert.org Site News daily 1 2009-12-28T16:17:26Z Don't destroy research http://www.fourmentinguilbert.org/postings/dont-destroy-research An appeal from scientists at the publicly funded Rothamsted Research. “On 27th May 2012 protesters are planning to destroy our Chemical Ecology group’s scientific research because it uses genetically modified wheat. Growing wheat has an environmental toll of extensive insecticide use to control aphid pests. The research, which is non-commercial, is investigating how to reduce that by getting the plants to repel aphids with a natural pheromone. We are appealing for protesters to call off the destruction and discuss the work.” 
John Pickett, Scientific Leader of Chemical Ecology, Rothamsted Research


“As scientists, we know only too well that we don’t have all the answers. But if the work is destroyed, we’ll lose years of work and we will never know whether it could reduce the environmental impact of wheat growing. Please sign our petition and oppose the destruction of our research.”  
Gia Aradottir, Postdoctoral Researcher, Insect Biology, Rothamsted Research

 

More information at: http://www.senseaboutscience.org/pages/rothamsted-appeal.html


]]> No publisher admin2 2012-05-04T12:23:00Z News Item New Layer of Genetic Information Discovered http://www.fourmentinguilbert.org/postings/what-does-determine-the-speed-of-protein-production By measuring the rate of protein production in bacteria, a team at University of California, San Francisco (UCSF) discovered that slight genetic alterations could have a dramatic effect. This was true even for seemingly insignificant genetic changes known as “silent mutations,” which swap out a single DNA letter without changing the ultimate gene product. To their surprise, the scientists found these changes can slow the protein production process to one-tenth of its normal speed or less. As described today in the journal Nature, the speed change is caused by information contained in what are known as redundant codons — small pieces of DNA that form part of the genetic code. They were called “redundant” because they were previously thought to contain duplicative rather than unique instructions.

This new discovery challenges half a century of fundamental assumptions in biology. It may also help speed up the industrial production of proteins, which is crucial for making biofuels and biological drugs used to treat many common diseases, ranging from diabetes to cancer.

To know more:

http://www.ucsf.edu/news/2012/03/11794/new-layer-genetic-information-discovered

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10965.html

 

]]> No publisher nathalie 2012-03-30T13:58:57Z News Item The spike of the virus http://www.fourmentinguilbert.org/postings/the-spike-of-the-virus Wherever there are bacteria (digestive tracts, contaminated water,...) you will find a group of virus called bacteriophages. These viruses infiltrate bacteria by drilling into the bacterial outer membrane. Once completely through all of a bug's defenses, the phages inject their DNA, which essentially turns the bacterium into phage-producing factories. Eventually, the microbes become filled with so many viruses that they burst, releasing a new horde of phages into the environment.


Scientists have long known that bacteriophages have a knack for infiltrating bacteria and that some begin their attack with a protein spike. But the tip of this spike is so small that no one knew what it was made of or exactly how it worked. Now a team of researchers has found a single iron atom at the head of the spike, a discovery that suggests phages enter bacteria in a different way than surmised: Forcefully rather than softening first the membrane. "It's like driving a nail or stake through the membrane of the bacteria." says virus experts.

Read the complete article at:

http://news.sciencemag.org/sciencenow/2012/02/bacteria-killing-viruses-wield-a.html?ref=hp

]]> No publisher nathalie 2012-03-02T09:16:04Z News Item DNA Sequencing is Now Improving Faster Than Moore's Law! http://www.fourmentinguilbert.org/postings/dna-sequencing-is-now-improving-faster-than-moores-law Two leading manufacturers of DNA sequencing instruments announce that they would introduce new machines this year capable of sequencing an entire human genome in a single day for a cost of $1,000 per genome.  

The speed of genome sequencing has far better than doubled every two years since 2003, when the first whole human genome was completed in 13 years’ time at a cost of $3.8 billion.

The parallel with Moore’s law indicates that, just as revolutionary computing and digital electronics applications have transformed society over the past four decades, innovations spurred by widely available gene sequencing could soon do the same. In cancer research for instance, widespread access to DNA sequencing will enable patients or oncologists to share the genomic details of their cancer over time, helping researchers more quickly identify links between mutations and various therapeutic responses.

Article source:

http://www.forbes.com/sites/techonomy/2012/01/12/dna-sequencing-is-now-improving-faster-than-moores-law/

]]> No publisher nathalie 2012-01-16T09:48:47Z News Item Gut Bacteria can control Diabetes http://www.fourmentinguilbert.org/postings/gut-bacteria-can-control-diabetes Insulin resistance is the harbinger of metabolic syndrome. Insulin resistance is when the body cannot use insulin effectively. As a result, blood sugar and fat levels rise. Therein lies the path to morbid obesity, diabetes, stroke, and heart problems.

A group of Brazilian researchers have taken a strain of mice normally known to be immune to insulin resistance, and made them insulin resistant (pre-diabetic) by changing their gut bacteria. They then gave the mice antibiotics, and by changing their gut bacteria again, reversed the process, curing them of the disease. Their research shows just how influential the bacteria living in our gut can be on our health."

 

More information:

http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001212

]]> No publisher nathalie 2012-01-13T10:02:14Z News Item Orange sweet potato a hit in Mozambique http://www.fourmentinguilbert.org/postings/orange-sweet-potato-a-hit-in-mozambique-1 Mozambique, like many poor countries, has a high prevalence of vitamin A deficiency, which can erode the immune system and cause blindness. Pregnant woman and young children in low-income countries are often hit the hardest, according to the WHO, and 600,000 children are estimated to die from a lack of vitamin A each year.  

Scientists have been working on the sweet potato for years, in the hope of battling deficiencies in vitamin A that afflict around 200 million of the world's poor. A programme aiming to persuade Mozambican villagers to switch from eating white and yellow sweet potato to a biofortified orange version, which contains more of a precursor of vitamin A,  has proved successful, with two-thirds of the targeted households adopting the new variety.

For three years, the biofortified sweet potato was created using conventional techniques to introduce six varieties to the Zambezia province.

The study, published in the British Journal of Nutrition last month (10 October) showed that the varieties were welcomed. It did not assess whether eating orange sweet potato caused levels of vitamin A to rise in the blood, though a previous, much smaller study in the same area had demonstrated this connection. "There has been a growing body of evidence to show that betacarotene [a precursor of vitamin A] in orange sweet potato is bioavailable and converted to vitamin A in the body," said Christine Hotz, former coordinator of HarvestPlus Nutrition, which led the research. HarvestPlus said that new, more drought-tolerant, orange-fleshed sweet potato varieties will be distributed to 120,000 households over the next two years.



The complete article is available at:

http://www.scidev.net/en/health/nutrition/news/orange-sweet-potato-a-hit-in-mozambique-say-inventors.html

]]> No publisher nathalie 2011-12-06T11:12:45Z News Item Quasi-science prevents an environmentally friendly agriculture and forestry http://www.fourmentinguilbert.org/postings/quasi-science-prevents-an-environmentally-friendly-agriculture-and-forestry At the end of this month, the world’s population will reach 7 billions; 1 billion are hungry, and 1 billion more are malnourished. In the next decades, there will be more humans. Limited land and water, costly energy for fertilizer, and climate change will ensure that more of them are hungry. Science and technology can contribute greatly to the solution. Why then is Europe regulating one part of the solution- GM (genetically modified) crops- as if they are a hazard?  

 

41 leading Swedish plant scientists urge politicians and environmental groups to take the necessary steps to change the relevant legislation so that all available knowledge can be used to develop sustainable agricultural and forest industries. Endorsed by British plant scientists, they have issued an important statement, expressing dismay, bewilderment and anger that legislation of GM crops in the EU is not based on science, ignores recent evidence, blocks opportunities to increase agricultural sustainability, and sustains the dominance of multinationals.

 

To know more:

 

http://www.plantsci.org.uk/news/leading-plant-researchers-call-science-based-gm-regulation

 

http://www.plantsci.org.uk/sites/default/files/Debate%20article.pdf

]]> No publisher nathalie 2011-10-21T09:47:35Z News Item Gamers help protein 3D structure modeling http://www.fourmentinguilbert.org/postings/gamers-help-protein-3d-structure-modeling One of the goals of computational biology is to predict the complete high-order structure of a protein from its amino acid sequence. Often reasonably good structures can be produced by modeling a new protein according to an already-known structure of a homologous protein, one with a similar sequence and presumably a similar structure. However, these structures can be inaccurate, and obviously this method will not work if no homologous structure is known.  

Foldit is an online game developed by the research team of Dr. David Baker that attempts to address this problem by combining an automated structure prediction program called ROSETTA with input from human players who manually remodel structures to improve them. Even though most of the players have little or no advanced biochemical knowledge, Foldit has already had some striking results improving on computational models. A paper in Nature Structural & Molecular Biology details some interesting new successes from the Foldit players.

 

Does this prove that gamers know more about folding proteins than computers do? Some of them might, but Foldit doesn’t really use human expertise. Rather, the game uses human intelligence to identify when the ROSETTA program has gone down the wrong path and figure out how to push it over the hump. When the human intelligences aren’t daring enough, or trust the system too much, Foldit doesn’t do any better than completely automated structural methods. When the human players are encouraged to challenge the computational results, however, the results can be striking. As Baker’s group are clearly aware, further development of the program needs to be oriented towards encouraging players to go further afield from the initial ROSETTA predictions.

 

The complete article by Michael W. Clarkson is at:

http://conflux.mwclarkson.com/2011/09/foldit-pmv-pr/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+ConformationalFlux+%28Conformational+Flux%29

 

The paper describing Foldit players results is available directly from David Baker's lab:

http://www.cs.washington.edu/homes/zoran/NSMBfoldit-2011.pdf

 

]]> No publisher nathalie 2011-09-22T18:09:08Z News Item RNA as an assembly line http://www.fourmentinguilbert.org/postings/synthetic-organization Delebecque and coworkers describe in Science the design and construction of self-assembling RNA scaffolds that spatially organize enzymes in bacterial cells. Internal organization in cells ranges from the simple colocalization of molecules in complexes to the compartmentalization of metabolic pathways within organelles.

Delebecque and coworkers designed and assembled multidimensional RNA structures and used them as scaffolds for the spatial organization of hydrogen-producing pathway.

RNA scaffolds served as docking sites to promote protein-protein interactions in cells and concentrate proteins and their products.

Several arrangements of organelle-like structures are generated and their effectiveness to increase hydrogen biosynthesis is measured.

This study is another demonstration that component spatial organization is key in the design of biosynthetic pathways. 3D modeling with a tool like LifeExplorer can help as it allows to construct, visualize and simulate cellular processes in a realistic way.

http://www.sciencemag.org/content/333/6041/470.short

]]> No publisher damien 2011-07-27T13:00:12Z News Item Escherichia chlori http://www.fourmentinguilbert.org/postings/chemical-evolution-of-a-bacteriums-genome Marlière and coworkers evolved the genetic program of an E. coli bacterium in order to replace one of the four DNA acid base by a chloro molecule analog.

This experiment is opening the road to xenobiology with modified organisms unable to exchange genetic material with living systems.

To go in the details of the paper:

http://onlinelibrary.wiley.com/doi/10.1002/ange.201100535/abstract?systemMessage=Wiley+Online+Library+will+be+disrupted+2+July+from+10-12+BST+for+monthly+maintenance

]]> No publisher nathalie 2011-07-04T05:30:00Z News Item Farewell Symposium for Andreas Engel http://www.fourmentinguilbert.org/postings/farewell-symposium-for-andreas-engel Andreas Engel, Professor for Structural Biology and former Chairman of the Biozentrum, retired from service to the Biozentrum and became Professor emeritus in October 2010. On February 11th, 2011, the Biozentrum bade farewell to its long standing member and remarkable researcher with a scientific symposium in his honor.  

Andreas Engel worked and taught at the Biozentrum for over 25 years. He focused on unraveling the structure and understanding the function of various membrane proteins. To analyze these proteins, he employed the techniques of electron crystallography, atomic force microscopy and scanning transmission electron microscopy.

Andreas Engel had a great influence on the development of 2D crystallization of membrane proteins, on the initial work of the 3D structure determination of the bacterial OmpF porin as well as the elucidation of the structure of human aquaporin-1. Together with Peter Agre (Baltimore) and Yoshinori Fujiyoshi (Kyoto) Engel’s work led to the first understanding of the atomic structure of a water channel membrane protein. It was in connection to this, that Peter Agre received the Nobel Prize for Chemistry in 2003, for his discovery of water channels.

 

For more information :

http://www.biozentrum.unibas.ch/bionews/bionews_20110214_engl.html

]]> No publisher nathalie 2011-03-30T13:56:32Z News Item The 3D architecture of the bacterial chromosome http://www.fourmentinguilbert.org/postings/the-3d-architecture-of-the-bacterial-chromosome A bacterial chromosome is so long that it must be highly compacted and folded to stand within the cellular space. Genetic studies coupled with fluorescence microscopy showed that it is well organized into isolated domains. These domains also move with order when the chromosome is duplicated and the two new chromosomes are separated each in one half the dividing cell.  

But 3D images of the chromosome within its intact cell were still very difficult to obtain due to the limitations of the current microscopy technics. The folding of the chromosome in space, its functional architecture have thus remained unclear.

A recent study shows such images. Thanks to a cryo-electron tomographic analysis, of the 3D architecture of the chromosome of the bacterium Bdellovibrio bacteriovorus. clearly appears. The salient observation is the versatile nature of this architecture: The chromosome can take several but very different shapes (twisted spiral vs. compact) providing the bacterium with different behaviors.

This study reinforces the idea of a pivotal role for one particular proteins called MreB. MreB is more and more thought to be a major actor in several cellular processes like the elongation, the nucleoid organization, the chromosome segregation, the chemoreceptor localization.

 

 

Reference:

Spiral architecture of the nucleoid in Bdellovibrio bacteriovorus
C. Butan, L.M. Hartnell, A.K. Fenton, D. Bliss, R.E. Sockett, S.Subramaniam and J.L. S. Milne
J. Bacteriology, 2010 Dec 10.

]]> No publisher nathalie 2011-02-07T09:26:55Z News Item LifeExplorer illustrates the front page of Molecular Microbiology http://www.fourmentinguilbert.org/postings/lifeexplorer-illustrates-the-front-page-of-molecular-microbiology The December 2010 issue contains several papers dedicated to bacterial cell division. The journal cover highlights a 3D model of the bacterial division machinery (the divisome) created with the LifeExplorer tool in collaboration with F.-X. Barre and N. Dubarry.  

More information:

http://onlinelibrary.wiley.com/doi/10.1111/mmi.2010.78.issue-5/issuetoc

]]> No publisher nathalie 2010-12-10T09:45:00Z News Item The eukaryotic ribosome has revealed its structure http://www.fourmentinguilbert.org/postings/the-eukaryotic-ribosome-has-revealed-its-structure Researchers at the Institute of Genetics and Molecular and Cell Biology (CNRS / University of Strasbourg / Inserm) have determined the first atomic structure of an eukaryotic ribosome (yeast ribosome). The eukaryotic ribosome, currently the largest asymmetric biological molecule, is an essential machinery of the cell for proteins synthesis from genetic information. It interacts with many proteins and has a key role in various cellular processes.

In 2009, the Nobel Prize in Chemistry rewarded researchers who first determined in 2000 the first structure at atomic resolution of the bacterial ribosome. The race for revealing the high resolution structure of the eukaryotic ribosome was then initiated.

More information on:

http://www2.cnrs.fr/presse/communique/2042.htm

]]> No publisher nathalie 2010-11-30T13:20:00Z News Item Bacteria self-assemble in a composite material for civil engineering http://www.fourmentinguilbert.org/postings/bacteria-self-assemble-in-a-composite-material-for-civil-engineering Researchers have designed bacteria that can produce a special glue to knit together cracks in concrete structures.  

The genetically modified microbe (Bacillus subtilis) has been programmed to swim down fine cracks in concrete. Once at the bottom, the resulting clumping of bacteria activates the concrete repair process and the cells differentiate into three types: cells which produce calcium carbonate crystals, cells which become filamentous —acting as reinforcing fibers — and thirdly cells that produce a glue that acts as a binding agent and fills the gap. The whole ultimately hardens to the same strength as the surrounding concrete.


Jennifer Hallinan says that "this could be particularly useful in earthquake zones where hundreds of buildings have to be flattened because there is currently no easy way of repairing the cracks and making them structurally sound."
Regarding potential risks to the environment, the microbe spores start germinating only when they make contact with concrete — triggered by the very specific pH of the material — and they have a built-in self-destruct gene that prevents them from proliferating away from the concrete target.

More information at:

http://www.msnbc.msn.com/id/40201539/ns/technology_and_science-future_of_energy/

]]> No publisher nathalie 2010-11-16T11:15:40Z News Item