Microbiology

The bacterium Clostridium difficile causes antibiotic-related diarrhea and is a growing problem in the hospital environment and elsewhere in the community. Understanding how the microbe colonizes the human gut when other "healthy" microbes have been destroyed during a course of antibiotics might lead to new ways to control infection.


A parasitic fungus - Ophiocordyceps camponoti-rufipedis, known as the "zombie ant fungus" - must kill its ant hosts outside their nest to reproduce and transmit their infection,so they manipulate its victims to die in the vicinity of the colony, ensuring a constant supply of potential new hosts, according to a new paper.

 Previous research shows that zombie ant fungi control the behavior of carpenter ant workers -- Camponotus rufipes -- to die with precision attached to leaves in the understory of tropical forests, noted study lead author Raquel Loreto, doctoral candidate in entomology, Penn State's College of Agricultural Sciences. 

It sounds like science fiction, but a new paper in the journal BioEssays
 says that bacteria within us — which outnumber our own cells about 100-fold — may very well be affecting both our cravings and moods to get us to eat what they want, and often are driving us toward obesity. 

The scholars from UC San Francisco, Arizona State University and University of New Mexico concluded that from a review of the recent scientific literature that microbes influence human eating behavior and dietary choices to favor consumption of the particular nutrients they grow best on, rather than simply passively living off whatever nutrients we choose to send their way.


Bacteria's ability to destroy viruses has been a mystery but researchers say they now have a clear picture of the bacterial immune system and say its unique shape is likely why bacteria can so quickly recognize and destroy their assailants.

The researchers drew what they say is the first-ever picture of the molecular machinery, known as Cascade, which stands guard inside bacterial cells. To their surprise, they found it contains a two-strand, unencumbered structure that resembles a ladder, freeing it to do its work faster than a standard double-helix would allow.


Researchers have discovered a highly virulent, multi-drug resistant form of the pathogen Pseudomonas aeruginosa, in patient samples in Ohio. Their investigation suggests that the particular genetic element involved, still rare in the United States, has been spreading unnoticed and that surveillance is urgently needed.  

The P. aeruginosa contained a gene for a drug resistant enzyme called a metallo beta-lactamase. Beta-lactamases enable broad-spectrum resistance to beta-lactam antibiotics, including carbapenems, cephalosporins, and penicillins, because they can break the four atom beta-lactam ring, a critical component of these antibiotics' structure.


Our immunosensory system detects virus such as influenza via specific characteristics of viral ribonucleic acid - and the immune system's ability to prevent viruses from using molecular camouflage to escape detection is quite good.

But how that works has been a mystery. Researchers have discovered that our immunosensory system attacks viruses on a molecular level to keep rotaviruses, a common cause of diarrheal epidemics, at bay. The results have been published in the renowned journal Nature.


The body's assailants are cleverer than previously thought. New research from Lund University in Sweden shows for the first time how bacteria in the airways can help each other replenish vital iron. The bacteria thereby increase their chances of survival, which can happen at the expense of the person's health.

The bacteria Haemophilus influenzae is a type of bacteria in the respiratory tract that can cause ear infections and worsen the prognosis for COPD patients. In rare cases, it can also lead to meningitis and septicaemia.


The Deepwater Horizon oil spill, a BP project in the Gulf of Mexico, began in April of 2010. The oil rig collapsed and it took some three months to cap the gusher. During that, concern was also on how to clean up the over four million barrels of oil in the environment

Among other approaches, the government used the Corexit oil dispersant, which emulsifies oil into balls and microbes, such as the genetically modified marine bacterium Alcanivorax borkumensis and the Colwellia species of bacteria, to consume it. And it worked, but a new paper says some of the more toxic components still remain.


A probiotic that prevents obesity could be on the horizon, at least if an animal model translates to humans. Bacteria that produce a therapeutic compound in the gut inhibit weight gain, insulin resistance and other adverse effects of a high-fat diet in mice, Vanderbilt University investigators say.

A lot would have to happen before this could move to human studies - regulatory hurdles and raising millions of dollars in venture capital, but the findings in the Journal of Clinical Investigation have the researchers excited because they suggest that it may be possible to manipulate the bacterial residents of the gut — the gut microbiota — to treat obesity and other chronic diseases.


Researchers have detected a previously unknown interaction between microorganisms and salt. When Escherichia coli cells are introduced into a droplet of salt water and left to dry, bacteria manipulate the sodium chloride crystallisation to create biomineralogical biosaline 3D morphologically complex formations, where they hibernate.

Afterwards, by rehydrating the material, bacteria are revived. The discovery was made by chance with a home microscope but made the cover of Astrobiology because it may be a way to find signs of life on other planets.