Science
19 views | +0 today
Follow
Your new post is loading...
Your new post is loading...
Rescooped by ALBERTO CHECA from Natural Products Chemistry Breaking News
Scoop.it!

Mahorones, Highly Brominated Cyclopentenones from the Red Alga Asparagopsis taxiformis

Mahorones, Highly Brominated Cyclopentenones from the Red Alga Asparagopsis taxiformis | Science | Scoop.it

The red alga Asparagopsis taxiformis (Rhodophyta, Bonnemaisoniaceae) has been shown to produce a large diversity of halogenated volatile organic compounds, with one to four carbons. As the distribution of this alga may expand worldwide, we implemented a research program that aims to understand the functions of its specialized metabolome in marine ecosystems. Phytochemical investigations performed on A. taxiformis gametophyte stages from the Indian Ocean revealed two new highly brominated cyclopentenones named mahorone (1) and 5-bromomahorone (2). They are the first examples of natural 2,3-dibromocyclopentenone derivatives. Their structure elucidation was achieved using spectrometric methods including NMR and MS. A standardized ecotoxicological assay was used as an assessment of their role in the environment, revealing high toxicities for both compounds (EC50 0.16 μM for 1 and 2). Additionally, both compounds were evaluated in antibacterial, antifungal, and cytotoxicity assays. Compounds 1 and 2 exhibit mild antibacterial activities against the human pathogen Acinetobacter baumannii.


Stéphane Greff †, Mayalen Zubia ‡, Grégory Genta-Jouve §, Lionel Massi , Thierry Perez †, andOlivier P. Thomas *† Institut Méditerranéen de Biodiversité et d’Ecologie Marine et Continentale, IMBE UMR 7263 CNRS/IRD/Aix-Marseille Université/Université d’Avignon et des Pays du Vaucluse, Station Marine d’Endoume, rue de la Batterie des Lions, 13007 Marseille, France‡ Agence pour la Recherche et la Valorisation Marine, ARVAM, 97490 Sainte-Clotilde, La Réunion, France§ Laboratoire de Pharmacognosie, UMR 8638 CNRS, Université Paris Descartes, Sorbonne Paris Cité, Faculté des Sciences Pharmaceutiques et Biologiques, 4 avenue de l’Observatoire, 75006 Paris, France Nice Institute of Chemistry-PCRE, UMR 7272 CNRS, Université de Nice Sophia-Antipolis, Faculté des Sciences, Parc Valrose 06108, Nice, FranceJ. Nat. Prod., Article ASAPDOI: 10.1021/np401094hPublication Date (Web): April 18, 2014




Via NatProdChem
more...
No comment yet.
Rescooped by ALBERTO CHECA from Plant Biology Teaching Resources (Higher Education)
Scoop.it!

Nature: Rate of tree carbon accumulation increases continuously with tree size

Nature: Rate of tree carbon accumulation increases continuously with tree size | Science | Scoop.it

"Forests are major components of the global carbon cycle, providing substantial feedback to atmospheric greenhouse gas concentrations.... Here we present a global analysis of 403 tropical and temperate tree species, showing that for most species mass growth rate increases continuously with tree size."

Green dots are eucalyptus and red are coast redwoods - very big trees and still growing!


Via Mary Williams
more...
Mary Williams's curator insight, January 16, 2014 3:24 AM

This study shows that although the rate of carbon fixed per leaf may be lower for larger trees, it's made up for by the fact that leaf area scales with the square of trunk diameter- so big trees are major carbon fixers.

(In other words, let's protect our old-growth forests!).

Rescooped by ALBERTO CHECA from Glossarissimo!
Scoop.it!

(EN) - Glossary of Biotechnology Terms | Kimball Nill

(EN) - Glossary of Biotechnology Terms | Kimball Nill | Science | Scoop.it

"Glossary of Biotechnology Terms by Kimball Nill"


Via Stefano KaliFire
more...
No comment yet.
Rescooped by ALBERTO CHECA from healthcare technology
Scoop.it!

Imaging technology could unlock mysteries of a childhood disease: respiratory syncytial virus (RSV)

Imaging technology could unlock mysteries of a childhood disease: respiratory syncytial virus (RSV) | Science | Scoop.it

By the time they're two, most children have had respiratory syncytial virus (RSV) and suffered symptoms no worse than a bad cold. But for some children, especially premature babies and those with underlying health conditions, RSV can lead to pneumonia and bronchitis - which can require hospitalization and have long-term consequences.

 

A new technique for studying the structure of the RSV virion and the activity of RSV in living cells could help researchers unlock the secrets of the virus, including how it enters cells, how it replicates, how many genomes it inserts into its hosts - and perhaps why certain lung cells escape the infection relatively unscathed. That could provide scientists information they need to develop new antiviral drugs and perhaps even a vaccine to prevent severe RSV infections.

 

"We want to develop tools that would allow us to get at how the virus really works," said Philip Santangelo, an associate professor in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. "We really need to be able to follow the infection in a single living cell without affecting how the virus infects its hosts, and this technology should allow us to do that."

 more at http://www.medicalnewstoday.com/releases/270726.php
Via nrip
more...
No comment yet.
Scooped by ALBERTO CHECA
Scoop.it!

The hottest articles published in Trends in Biotechnology :: Peccoud ...

The hottest articles published in Trends in Biotechnology :: Peccoud ... | Science | Scoop.it
As member of the editorial board of Trends in Biotechnology, I thought it might be useful to identify the Trends in Biotechnology articles that generate the most buzz. Below are the articles that have been mentioned in social ...
more...
No comment yet.
Scooped by ALBERTO CHECA
Scoop.it!

Lost Microbes are Eroding Amazon's Ability to Capture Carbon (Op-Ed) - LiveScience.com

Lost Microbes are Eroding Amazon's Ability to Capture Carbon (Op-Ed) - LiveScience.com | Science | Scoop.it
LiveScience.com Lost Microbes are Eroding Amazon's Ability to Capture Carbon (Op-Ed) LiveScience.com Beneath the lush forests of the Amazon is a whole different level of diversity that new research says may be one of the keys to understanding how...
more...
No comment yet.
Rescooped by ALBERTO CHECA from Natural Products Chemistry Breaking News
Scoop.it!

A mass spectrometry–guided genome mining approach for natural product peptidogenomics

A mass spectrometry–guided genome mining approach for natural product peptidogenomics | Science | Scoop.it

Peptide natural products show broad biological properties and are commonly produced by orthogonal ribosomal and nonribosomal pathways in prokaryotes and eukaryotes. To harvest this large and diverse resource of bioactive molecules, we introduce here natural product peptidogenomics (NPP), a new MS–guided genome-mining method that connects the chemotypes of peptide natural products to their biosynthetic gene clusters by iteratively matching de novo tandem MS (MSn) structures to genomics-based structures following biosynthetic logic.

 


Via NatProdChem
more...
No comment yet.
Rescooped by ALBERTO CHECA from Amazing Science
Scoop.it!

Parasites Use Sophisticated Biochemistry to Take Over Their Hosts

Parasites Use Sophisticated Biochemistry to Take Over Their Hosts | Science | Scoop.it
Parasites that take over hosts, effectively turning them into zombies, are far from rare. But only recently have scientists started to work out the sophisticated biochemistry that the parasites use.

 

n the rain forests of Costa Rica lives Anelosimus octavius, a species of spider that sometimes displays a strange and ghoulish habit. From time to time these spiders abandon their own webs and build radically different ones, a home not for the spider but for a parasitic wasp that has been living inside it. Then the spider dies — a zombie architect, its brain hijacked by its parasitic invader — and out of its body crawls the wasp’s larva, which has been growing inside it all this time.

 

There are many of such examples of zombies in nature. They are far from rare. Viruses, fungi, protozoans, wasps, tapeworms and a vast number of other parasites can control the brains of their hosts and get them to do their bidding. But only recently have scientists started to work out the sophisticated biochemistry that the parasites use.

 

“The knowledge that parasites can manipulate their hosts is old. The new part is how they do it,” said Shelley Adamo of Dalhousie University in Nova Scotia, a co-editor of the new issue. “The last 5 to 10 years have really been exciting.”

 

In the case of the Costa Rican spider, the new web is splendidly suited to its wasp invader. Unlike the spider’s normal web, mostly a tangle of threads, this one has a platform topped by a thick sheet that protects it from the rain. The wasp larva crawls to the edge of the platform and spins a cocoon that hangs down through an opening that the spider has kindly provided for the parasite.

To manipulate the spiders, the wasp must have genes that produce proteins that alter spider behavior, and in some species, scientists are now pinpointing this type of gene. Such is the case with the baculovirus, a virus sprinkled liberally on leaves in forests and gardens. (The cabbage in a serving of coleslaw carries 100 million baculoviruses.)

 

David P. Hughes of Penn State University and his colleagues have found that a single gene, known as egt, is responsible for driving the caterpillars up trees. The gene encodes an enzyme. When the enzyme is released inside the caterpillar, it destroys a hormone that signals a caterpillar to stop feeding and molt.

 

Dr. Hughes suspects that the virus goads the caterpillar into a feeding frenzy. Normally, gypsy moth caterpillars come out at night to feed and then return to crevices near the bottom of trees to hide from predators. The zombie caterpillars, on the other hand, cannot stop searching for food.

“The infected individuals are out there, just eating and eating,” Dr. Hughes said. “They’re stuck in a loop.”

 

Whether humans are susceptible to this sort of zombie invasion is less clear. It is challenging enough to figure out how parasites manipulate invertebrates, which have a few hundred thousand neurons in their nervous systems. Vertebrates, including humans, have millions or billions of neurons, and so scientists have made fewer advances in studying their zombification.

 


Via Dr. Stefan Gruenwald
more...
No comment yet.
Rescooped by ALBERTO CHECA from Rhizobium Research
Scoop.it!

The rhizosphere microbiome: significance of plant beneficial, plant pathogenic, and human pathogenic microorganisms

The rhizosphere microbiome: significance of plant beneficial, plant pathogenic, and human pathogenic microorganisms | Science | Scoop.it

Microbial communities play a pivotal role in the functioning of plants by influencing their physiology and development. While many members of the rhizosphere microbiome are beneficial to plant growth, also plant pathogenic microorganisms colonize the rhizosphere striving to break through the protective microbial shield and to overcome the innate plant defense mechanisms in order to cause disease. A third group of microorganisms that can be found in the rhizosphere are the true and opportunistic human pathogenic bacteria, which can be carried on or in plant tissue and may cause disease when introduced into debilitated humans. Although the importance of the rhizosphere microbiome for plant growth has been widely recognized, for the vast majority of rhizosphere microorganisms no knowledge exists. To enhance plant growth and health, it is essential to know which microorganism is present in the rhizosphere microbiome and what they are doing. Here, we review the main functions of rhizosphere microorganisms and how they impact on health and disease. We discuss the mechanisms involved in the multitrophic interactions and chemical dialogues that occur in the rhizosphere. Finally, we highlight several strategies to redirect or reshape the rhizosphere microbiome in favor of microorganisms that are beneficial to plant growth and health.


Via Francis Martin, Praveen Rahi, Jean-Michel Ané, IvanOresnik
more...
No comment yet.
Rescooped by ALBERTO CHECA from Amazing Science
Scoop.it!

Genetically identical bacteria can behave differently depending on organelle distribution

Genetically identical bacteria can behave differently depending on organelle distribution | Science | Scoop.it

Genetically identical bacteria can behave in radically different ways. New study shows when bacterial cell divides there can be uneven distribution of cellular organelles. Resulting cells can behave differently from each other, depending on which parts they received in the split.

 

As these bacterial cells divide, chemotaxis machinery (bright blue and red) localize in one daughter cell. This phenomenon is crucial in the bacteria's struggle for survival. The more diversity a population of bacteria has, the more likely it will contain individuals able to take advantage of a new opportunity or overcome a new threat, including the threat posed by an antibiotic.


In a recent study, researchers at the University of Washington showed that when a bacterial cell divides into two daughter cells there can be an uneven distribution of cellular organelles. The resulting cells can behave differently from each other, depending on which parts they received in the split.

"This is another way that cells within a population can diversify. Here we've shown it in a bacterium, but it probably is true for all cells, including human cells," said Dr. Samuel Miller, UW professor of microbiology, genome sciences, and medicine and the paper's senior author.

 

Bridget Kulasekara, who obtained a Ph.D in the UW Molecular and Cellular Biology Program, was the paper's lead author. Other contributors included: Hemantha Kulasekara, Matthias Christen, and Cassie Kamischke, who work in Miller's lab, and Paul Wiggins, UW assistant professor of physics and bioengineering. The paper appears in the online journal eLife.

 

In an earlier paper, Miller and his colleauges showed that when bacteria divided, the concentration of an important regulatory molecule, called cyclic diguanosine monophosphate (c-di-GMP). was unevenly distributed between the two progeny. c-di-GMP is a second messenger molecule. That finding was published in the journal Science in 2010.

 

More information: Kulasekara et al. c-di-GMP heterogeneity is generated by the chemotaxis machinery to regulate flagellar motility. ELife. 2013;2:e01402. DOI: 10.7554/eLife.01402

 

Chisten M et al. Asymmetrical Distribution of the Second Messenger c-di-GMP upon Bacterial Cell Division. Science. 2010; 328(5983):1295-1297 DOI: 10.1126/science.1188658


Via Dr. Stefan Gruenwald
more...
Ashlyn Johnson's curator insight, January 7, 2014 1:21 PM

This blog really interest me because it is about cells and how sells work and the process works.

Scooped by ALBERTO CHECA
Scoop.it!

MIT researchers find a drug that helps erase traumatic memories in mice - The Boston Globe

MIT researchers find a drug that helps erase traumatic memories in mice - The Boston Globe | Science | Scoop.it
In mind-control experiments over the past few years at the Massachusetts Institute of Technology, scientists have planted a false memory, activated a real memory, and, now, a team announced Thursday, erased a memory altogether.
more...
No comment yet.