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There are species of fungi that inhabit the sub-zero temperatures of Antarctica, and until now it wasn’t known how they survive – and even thrive – in these icy conditions. A researcher at the National Institute of Polar Research, Japan, studied the Antarctic yeast Mrakia blollopis and found that one strain of the micro-organism consumes a lot of energy during growth, in order to cope with the cold. By sacrificing this energy instead of storing it, the SK-4 strain of M. blollopis can stop its cells from freezing at temperatures below freezing.

A new study by scientists at King Abdullah University of Science and Technology (KAUST), Saudi Arabia, has found a bacterial wastewater treatment system that could help limit the spread of antibiotic resistance. Many treatment facilities use two types of membrane bioreactors (MBRs), which use either aerobic or anaerobic bacteria to break down the contaminants in wastewater. The effects of the various household pollutants on the structure of the bacterial communities has not been studied, and there are concerns that constant exposure to antibiotics in the wastewater could encourage the bioreactor bacteria to develop drug resistance, which could then spread. In their investigation, the KAUST research team found that although there were changes in the expression of genes in both types of bacteria, antibiotic resistance gene levels were significantly lower in the anaerobic system. The group suggest that these results provide a strong argument for using anaerobic MBRs over aerobic.

A newly discovered bacterium, found down a South African gold mine by scientists at the Blue Marble Space Institute of Science, USA, could potentially be used as a model for alien life. Desulforudis audaxviator was isolated 2.8km below ground in an extremely inhospitable environment – lacking light, oxygen and carbon – and instead seemed to thrive on the radiation from uranium, using it to drive biochemical processes. Since radiation also exists in space, the researchers wonder if other life forms exist elsewhere in the universe, surviving on cosmic rays in a similar way to D. audaxviator.

New research from scientists across several French institutions has shown that Staphyloccocus aureus can use the fatty acids naturally found in the human body to resist triclosan, an antibacterial agent found in a wide variety of household products. Triclosan blocks the ability of some bacteria, including S. aureus, to create the fatty acids they use for growth and virulence. The study showed that, when triclosan is introduced, S. aureus is able use the fatty acids in its surrounding environment – in this case, in the infected individual’s body – to continue growing instead.

Enteroaggregative Escherichia coli is a bacterium that can cause severe diarrhoea and growth problems in children, but for some reason, some of them carry the micro-organism in their guts with mild or even no symptoms. To understand why this might be the case, researchers from different Danish institutions studied the gut microbiome of over 170 children between the ages of 0 and 6 years over the course of a year. The study found that the enteroaggregative E. coli was prevalent among the children, but only half of them experienced gastrointestinal symptoms, with most of them mild. However, the scientists noticed that many of the E. coli strains isolated were resistant to antibiotics. This suggests that any prescribed antibiotic treatments may have devastated the natural gut flora without killing the E. coli, allowing it to then take over and cause more severe symptoms.

There are many consequences of climate change, but a new study by scientists at various institutions in Japan found that the temperature rise could kill off some species of insect by proxy. The investigation showed that, when exposed to higher temperatures, heat-sensitive bacteria living symbiotically in insects’ guts can die, which can lead to the death of their hosts. This could mean disaster for insects such as the Southern green shield bug, as they rely on their specific set of gut microbes to survive. In lab tests, the researchers raised the insects at temperatures 2.5°C higher than normal, and none of the young bugs survived to adulthood.

Researchers at the University of Illinois, USA, have discovered that soil microbes thrive better in undisturbed agricultural land. In the study, no-till agriculture and conservation tillage – where the disturbance of the soil is kept to a minimum – appeared to allow the micro-organisms to flourish as the natural soil structure is preserved. Previously, most studies into the effect of tillage on soil microbes have not spanned across multiple sites. In an effort to look for patterns, the Illinois research team analysed data from 62 studies and were able to confirm the connection between soil tillage and microbial activity.

A recent study of dog microbiomes shows that it is possible to predict inflammatory bowel disease (IBD) by just looking at their faeces. Researchers at the University of California, San Diego, USA, analysed canine stool samples and found similarities in the microbial communities of IBD-affected animals. The scientists were able to then predict which dogs had IBD with over 90% accuracy. However, as the gut microbiomes of dogs and humans are different, it is not possible to use them as animal models for humans with IBD.

Malaria is caused by Plasmodium parasites that are carried by mosquitoes, transmitted to people through insect bites, but how do the parasites infect mosquitoes in the first place? Researchers at John Hopkins Bloomberg School of Public Health, USA, have now discovered the fungus a compromises the mosquito’s immune systems as Penicillium chrysogenum. This infection makes the bugs more susceptible in turn to infection by Plasmodium parasites. The finding may help answer questions about differing levels of transmission activity across different regions, and the research could potentially be used in the fight against mosquito-borne diseases like malaria.

The first catalogue of the bacteria inside pigs’ guts has now been published by an international group of researchers from France, Denmark, Norway and China. After analysing faecal samples from across multiple farms in different countries, the scientists were able to identify huge numbers of both known and unknown bacteria. Importantly, their findings showed differences between pig gut microbiomes from different countries, such as the effect of the prohibition of antibiotic-use in growth promotion in Denmark and France. The study showed that bacteria living within Danish and French pigs appeared to have fewer resistance genes, although they still carry genes that can give resistance to many antibiotics.