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Researchers at Kansas State University, USA, have found that mosquitoes from the Culex genus seem unable to transmit Zika virus – a welcome piece of information in the fight against this emerging disease. Studying these insects over a period of time, the research team noticed that the virus did not replicate within the species, but instead eventually died out. Knowing that Culex mosquitoes can be taken out of the equation ensures that those studying the transmission of Zika don’t end up wasting time and resources looking the wrong way, and can instead focus on the known vectors: Aedes mosquitoes.

Honey has often been studied for its antimicrobial properties, and new research from scientists at the University of Southampton, UK, has shown that the mānuka variety can limit the growth of bacterial biofilms. Biofilms are thin layers of microbes that build up on various surfaces, and their presence on things like medical devices can stop the technology from working properly or cause infections in a patient. The study saw different strengths of mānuka honey added to cultured strains of Escherichia coli and Proteus mirabilis – the two bacterial species that commonly cause infections through long-term catheter use. The results showed that the honey made it more difficult for the bacteria to stick together to form a biofilm, even at the lowest strength – a promising finding that could potentially be used to curb biofilms.

Recently, scientists at the University of Tokyo, Japan, have revealed the secret behind tardigrades’ incredible survival skills. Tardigrades are microscopic aquatic animals that can somehow survive boiling, freezing and radiation, and it appears to be all down to a protein that shields their DNA from extreme conditions. In lab tests, the researchers inserted this protein, named Dsup (damage suppressor), into cultured human cells, then exposed them to X-rays. The protected cells showed much less damage than they would had they not been Dsup treated. The research team say that this discovery could potentially be used for the protection of human cells from things like radiation.

A steel-corroding species of marine microbes has been found to be able to tolerate oxygen-rich environments, unlike others in its family. Researchers at the Bigelow Laboratory for Ocean Sciences, USA, and the University of Tübingen, Germany, have found that Mariprofundus sp. DIS-1 contains a set of genes that allow it to thrive in aerobic conditions and therefore may be the culprit in the initial rusting on things like ships, bridges and pipelines. The research team explain that understanding the microbiology behind the corrosion of marine infrastructure is the first step towards understanding how to mitigate it.

A new study by researchers at The Hong Kong Polytechnic University, Hong Kong, has found that Vibrio parahaemolyticus, a marine bacterium, has a gene for resistance against antibiotics. Strangely, this gene has almost always been found in non-marine microbes, and had never been seen in V. parahaemolyticus before, so it seems that the gene may have been passed on from a different bacterial species. Further investigation showed that the DNA molecule containing the gene, called a plasmid, can be transferred to the unrelated species E. coli – potentially where it came from in the first place.

Researchers at Purdue University, USA, may soon been able to find out if food has been contaminated by bacteria with a new detection technique: making E. coli glow in the dark. The scientists altered a bacteriophage – a virus that infects specific bacteria – so that it causes a severe disease-causing strain of E. coli to glow when infected. This new method can show if food is tainted in a much shorter time frame than traditional ones, which could be key to not allowing the distribution of contaminated items.

The type VI secretion system (T6SS) is a mechanism that some bacteria use against their rivals for nutrients, and a team of scientists from the University of Basel, Switzerland, have discovered that bacteria can utilise their ally’s weapons. T6SS acts like a spear gun loaded with toxins that bacteria inject into their competition to neutralise them. However, the study found that when a bacterium harpoons a close relative, the injected bacterium takes the spear tip, disassembles the protein components and adds them to their own arsenal. Further tests demonstrated that even defective bacteria, that are lacking the proteins to make their own harpoons, can recycle a friendly bacterium’s guns to create their own weapon.

Citrus greening disease, also known as Huanglongbing, is caused by Candidatus liberibacter spp. bacteria and can leave swathes of ruined citrus plants in its wake. A research team at the University of Florida, USA, may have a solution in an antibiotic called oxytetracycline. Injecting the antibiotic directly into infected trees’ trunks ensures it is delivered throughout the plant, from roots to leaves. This kind of application means that the treatment isn’t affected by things like rain, which could flush it out if only applied to leaves, for example. These findings could mean an answer to a very costly disease.

Based on the “feed a cold, starve a fever” theory, researchers at Yale University, USA, decided to investigate the effects of giving nutrients during either a viral or a bacterial infection. In lab tests, mice were infected with Listeria monocytogenes, the bacterium that often causes food poisoning, and the ones force-fed with glucose died whereas those left without food recovered. On the other hand, with mice infected with a flu virus, the glucose-fed individuals survived but those not given food died. Further research showed that the animals’ metabolic needs changed depending on what the immune system was fighting off.

A new bacterium related to Bacillus anthracis – which causes anthrax – has been discovered by researchers from the Robert Koch Institute, Germany, and it seems to mimic the symptoms of anthrax in various mammals in Africa. This novel pathogen looks more similar genetically to Bacillus cereus, another related species which can cause food poisoning, but contained two sections of genetic material that have only been seen in B. anthracis. This addition makes the behaviour of the new species closer to that of the anthrax-causing microbe, despite appearing to have evolved from a B. cereus strain. These results show that more surveillance may be needed to understand this new microbe’s impact on both animal and human health.