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A species of marine bacteria, called Vibrio alginolyticus, possesses a natural ability to seek out food as quickly as possible, which could inspire novel human therapies using Escherichia coli, suggests an international research team lead by the University of Edinburgh, UK. The study found that the ocean microbes that travel fastest change direction most often, so that they could target the nutrients they need more precisely. They also found that the closer V. alginolyticus were to the food, the faster they swam. The scientists believe that E. coli could be engineered to include the genes that give V. alginolyticus such abilities, which can then be used to deliver drugs precisely.

New research has revealed that Pneumocystis carinii, a fungus that infects piglets and has commonly been thought to be less dangerous than some other pathogens, may be making it easier for secondary respiratory infections to take hold. Scientists from the University of Veterinary Medicine, Vienna, Austria, investigated piglets of various ages and found that P. carinii appeared to weaken the animals’ lungs, allowing bacteria to co-infect at the same time.

Researchers at Purdue University, USA, have discovered a way of extending the shelf life of milk – by quickly heating and then cooling it. The study found that increasing the temperature of milk by 10°C for less than a second killed off more than 99% of the bacteria that remained after pasteurisation. This method means that milk could last several weeks longer than it currently does. The scientists hope that these findings could help reduce food waste.

For the first time, a rare compound has been found in the Doratomyces microsporus fungus, which had previously only been found in an Antarctic sponge. Researchers at the University of Veterinary Medicine, Vienna, Austria, induced the fungus into producing several compounds, including cyclo-(L-proline-L-methionine) – or cPM – by applying valproic acid. The cPM compound is known to increase the activity of other antimicrobial compounds, and the study showed that it gave the antibiotic ampicillin a boost against ampicillin-resistant bacteria. Lab tests showed that these microbes were more susceptible to ampicillin when combined with cPM, even at lower doses of the drug.

Researchers at Swansea University, UK, have been working on killing Aedes aegypti mosquitoes with Metarhizium brunneum, a fungus that has previously been used to control populations of other insects. The study found that M. brunneum blastospores – particles that the fungus produces through budding – can attack and kill mosquito larvae in freshwater, where the bugs hatch. The blastospores release mucus that allows them to stick to the surface of the larvae, then they penetrate the outer protective layer called the larval cuticle. The insects also ingest blastospores found in the water, turning it into a double attack from both inside and out. With such brutal tactics, the research team noticed that infected larvae die within 24 hours of blastospore contact. This research could potentially help control the spread of A. aegypti mosquitoes, which are responsible for the spread of diseases like dengue and Zika.

Extremely cold and saturated with oxygen, Antarctic waters do not seem the sort of place to harbour life, but Euplotes forcardii – a single-celled micro-organism – tolerates this hostile environment exceedingly well. To find out more about how life can adapt to such harsh conditions, scientists from the University of Camerino, Italy, looked at the genetic make-up of the microbe. The study found that some genes only expressed by E. forcardii specifically helped protect it from oxidative stress – a build-up of toxic molecules naturally produced when cells interact with oxygen. The research team believe that these protective genes evolved in E. forcardii as the micro-organism adapted to living in the Antarctic.

‘Adapt or die out’ seems like a harsh mantra to live by, but this could be what drove humans to be what they are today, potentially with a little help from viruses. Scientists at Stanford University, USA, studied the evolution of human proteins – molecules that perform functions like transport oxygen around the body or fight infections – and found that the ones that interacted with viruses mutated three times more often than those that had no contact with the microbes. These findings reveal the impact of how viruses have shaped human genetics, and could help towards finding new solutions to fight them.

In most organisms, the older they get, the more ‘defects’ they acquire. Since bacteria reproduce by dividing in two, what happens when older microbes – which have more defects in their genetic code – replicate? Are the defects split evenly between the two new bacteria? Scientists at the University of Copenhagen, Denmark, studied several bacterial communities and noticed that colonies left to their own devices divided almost symmetrically, sharing the defects evenly. However, if the colonies were exposed to stress – heat, for example – one of the two new bacteria would collect all of the defects, leaving the other ‘young’ and refreshed.

New research from Tufts University School of Medicine, USA, reveals that individual bacteria in a population are not entirely identical, and we can use this to better fight infection. The study noticed that, within one community of Mycobacterium smegmatis – a non-pathogenic relative of M. tuberculosis – each microbe can vary in size. The smaller individuals were more susceptible to antibiotic treatment, as well as the bacteria at the beginning or the end of their cell division cycle. These findings could potentially mean that medicines are scheduled to be given at times the bacteria are weaker, shortening antibiotic treatment time for diseases like tuberculosis.

Scientists at the Alfred Wegener Institute, Germany, have recently discovered that when Emiliania huxleyi, the most common species of microalgae in the world’s oceans, is in a state of starvation, the microbes partially digest themselves in order to stay alive. As the open sea naturally lacks the phosphorus and nitrogen needed by microalgae to reproduce, it becomes a race for the nutrients when they do find their way into the water from external sources. Once the nutrients are depleted, E. huxleyi faces a famine situation that triggers a molecular mechanism, causing the algae to ‘eat’ themselves in order to survive until the next meal comes along.