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Very few bacterial species have been found that have the ability to photosynthesise, but researchers at the University of Southern Denmark have now discovered one more in a lake in the Gobi Desert. The study found that the genes allowing the bacteria to process sunlight into fuel is organised into cluster, which means it could be removed altogether and transferred to another bacterium. This means that, in principle, scientists could artificially make Escherichia coli photosynthetic. As E. coli shares many common traits with a variety of other bacteria and is easy to manipulate, if successful, the experiment could lead to more economic and efficient biofuel production.

Swapping microbes with other people sounds unpleasant, but new research led by researchers at the University of California, Berkeley, and Duke University, both USA, found that it means a wider microbial diversity. The study monitored the microbiomes of wild chimpanzees in Tanzania and noticed that the more sociable animals had increased diversity of gut micro-organisms. Researchers also found that unrelated chimps that spent time together had as similar gut microbiomes as mothers and their babies. This suggests that sharing germs through social interaction is as important for gut microbe diversity as the first point of exposure through birth.

It seems bizarre, but sometimes bacteria can affect whether or not the host of a disease-causing parasite can carry or transmit that disease. Sodalis glossinidius is one such species of bacteria – it allows the tsetse fly to be a carrier of the protozoa that cause African trypanosomiasis, or African Sleeping Sickness. Flies without the bacteria are unable to transmit the parasite. Scientists at the University of Salford, UK, will be attempting to exploit this fact by investigating how S. glossinidius’s genetic make-up influences the host–parasite relationship. The results of the study may lead to better solutions to control insect-borne diseases.

A new study from Duke Health, USA, has investigated why only some people come down with a stomach bug, while others get off scot-free. Healthy adults were first exposed to Escherichia coli, a common cause of bacteria-related stomach illnesses, such as ‘traveller’s diarrhoea’. The researchers then tested these volunteers and found differences in the activity of immune system-related genes, between the patients who showed severe symptoms and those who showed none. These findings suggest that some people may be genetically less, or more, prone to infection.

A team led by scientists at the European Academy of Bozen/Bolzano (EURAC), Italy, recently found the presence of the bacterium Helicobacteri pylori in the stomach of Ötzi, the 5,000-year-old “Iceman” preserved in a glacier until he was found in 1991. H. pylori can be found inside half of all humans today, and can be the cause of things like stomach ulcers in older people. This finding backs the theory that modern humans have been infected by H. pylori for thousands of years.

Researchers at the National University of Mexico discovered that there are microbes naturally growing on peanut shells, which could be exploited to clean air of pollutants. Fusarium, a genus of fungi, and Brevibacterium, a genus of bacteria, can both be cultivated on peanut shells. The peanut shells are then made into biofilters, where the micro-organisms consume and degrade pollutants in the atmosphere into non-toxic products.

Domoic acid is a toxin naturally produced by species of algae belonging to the Pseudo-nitzschia genus, particularly affecting shellfish. Scientists at the University of California, Santa Cruz, USA, investigated the toxin’s persistence in the marine life, long after the bloom had disappeared, and found that it had found its way into the muscle tissue of some commercial species of fish. Although the toxicity levels were well below regulated limits, being present in muscle tissue means it stays in the food web for much longer than if it was simply in the fish’s digestive system. These results could have implications in the seafood trade, and researchers will need to continue to monitor and predict when prolonged algal blooms occur.

Some of the most pathogenic bacteria in the world possess the ability to quickly overwhelm and kill their prey cells, by injecting toxic proteins into them – often using a process called type VI secretion (T6S). When first discovered in 2006, scientists believed this system was unstoppable, but a new study from Princeton University, USA, and the University of Basel, Switzerland, revealed that if the target cells are a large enough group, the predatory bacteria cannot overpower them all. Although the outer organisms are vulnerable to attack, if the group is big enough the inner cells can reproduce at a rate that means the pathogen is unable to take over.

The saying “you can’t teach an old dog new tricks” does not appear to apply to Moorella thermoacetica, a non-photosynthetic bacterium that scientists at the University of California, Berkeley, USA, have taught to photosynthesise. The researchers introduced an artificial photosynthesis system to the micro-organism, which converts carbon dioxide into acetic acid – a valuable chemical used in the production of things like paint and aspirin. These results highlight just one of the ways microbes can be exploited to sustainably and inexpensively produce useful compounds.

You may have had a lot of foot traffic coming in and out of your house last month, but for every human guest, you will have also had millions of bacterial guests. It may sound disgusting, but Dr Jack Gilbert, a researcher at the University of Chicago, USA, suggests it’s anything but. Studying the formation of microbial communities, Dr Gilbert explains that being exposed to other people’s microbes probably helps each of us build immunities to a range of things. He suggests that many social things we do may have evolved as a way to share bacteria – for example, kissing may promote healthy digestion and keep the immune system on its toes.