The International Space Station (ISS) is a closed system inhabited by microorganisms originating from life support systems, cargo, and crew that are exposed to unique selective pressures such as microgravity. To date, mandatory microbial monitoring and observational studies of spacecraft and space stations have been conducted by traditional culture methods, although it is known that many microbes cannot be cultured with standard techniques. To fully appreciate the true number and diversity of microbes that survive in the ISS, molecular and culture-based methods were used to assess microbial communities on ISS surfaces. Samples were taken at eight pre-defined locations during three flight missions spanning 14 months and analyzed upon return to Earth. The results reveal a diverse population of bacteria and fungi on ISS environmental surfaces that changed over time but remained similar between locations. The dominant organisms are associated with the human microbiome and may include opportunistic pathogens. This study provides the first comprehensive catalog of both total and intact/viable bacteria and fungi found on surfaces in closed space systems and can be used to help develop safety measures that meet NASA requirements for deep space human habitation. The results of this study can have significant impact on our understanding of other confined built environments on the Earth such as clean rooms used in the pharmaceutical and medical industries. https://doi.org/10.1186/s40168-019-0666-x
Posts tagged bacteria
The electricity-eating microbes that the researchers were hunting for belong to a larger class of organisms that scientists are only beginning to understand. They inhabit largely uncharted worlds: the bubbling cauldrons of deep sea vents; mineral-rich veins deep beneath the planet’s surface; ocean sediments just a few inches below the deep seafloor. The microbes represent a segment of life that has been largely ignored, in part because their strange habitats make them incredibly difficult to grow in the lab.
The last drug has fallen. Bacteria carrying a gene that allows them to resist polymyxins, the antibiotics of last resort for some kinds of infection, have been found in Denmark and China, prompting a global search for the gene. The discovery means that gram-negative bacteria, which cause common gut, urinary and blood infections in humans, can now become “pan-resistant”, with genes that defeat all antibiotics now available. That will make some infections incurable, unless new kinds of antibiotics are brought to market soon. Colistin, the most common polymyxin, is a last-resort treatment for infections with bacteria such as E. coli and Klebsiella that resist all other available antibiotics.
University of Southern California (USC) have discovered bacteria that survives on nothing but electricity — rather than food, they eat and excrete pure electrons. These bacteria yet again prove the almost miraculous tenacity of life — but, from a technology standpoint, they might also prove to be useful in enabling the creation of self-powered nanoscale devices that clean up pollution. Some of these bacteria also have the curious ability to form into ‘biocables,’ microbial nanowires that are centimeters long and conduct electricity as well as copper wires — a capability that might one day be tapped to build long, self-assembling subsurface networks for human use.
In the last few years, the microbiome (sometimes referred to as “the second genome”) has become a focus for the health conscious and for scientists alike. Studies like the Human Microbiome Project, a national enterprise to sequence bacterial DNA taken from 242 healthy Americans, have tagged 19 of our phyla (groupings of bacteria), each with thousands of distinct species. As Michael Pollan wrote in this magazine last year: “As a civilization, we’ve just spent the better part of a century doing our unwitting best to wreck the human-associated microbiota… . Whether any cures emerge from the exploration of the second genome, the implications of what has already been learned — for our sense of self, for our definition of health and for our attitude toward bacteria in general — are difficult to overstate.”
Oenococcus oeni is the main lactic acid bacterium that carries out the malolactic fermentation in virtually all red wines and in some white and sparkling wines. Oenococcus oeni possesses an array of metabolic activities that can modify the taste and aromatic properties of wine. There is, therefore, industrial interest in the proteins involved in these metabolic pathways and related transport systems of this bacterium. In this work, we report the characterization of the O. oeni ATCC BAA-1163 proteome.
Now, if you think about it, there’s something deeply puzzling here. Bacterial colonies, travelling flames, and coffee particles are all totally different systems, and there’s no reason to expect that they should obey the same mathematical laws of growth. So what’s behind this mysterious universality? Why do such different beasts play by the same rules?
The bacteria, Carbapenem-Resistant Enterobacteriaceae (CRE), kill up to half of patients who get bloodstream infections from them. In addition to spreading among patients, often on the hands of health care personnel, CRE bacteria can transfer their resistance to other bacteria within their family. This type of spread can create additional life-threatening infections for patients in hospitals and potentially for otherwise healthy people. Currently, almost all CRE infections occur in people receiving significant medical care in hospitals, long-term acute care facilities, or nursing homes.
A healthy adult human harbours some 100 trillion bacteria in his gut alone. That is ten times as many bacterial cells as he has cells descended from the sperm and egg of his parents. These bugs, moreover, are diverse. Egg and sperm provide about 23,000 different genes. The microbiome, as the body’s commensal bacteria are collectively known, is reckoned to have around 3m. Admittedly, many of those millions are variations on common themes, but equally many are not, and even the number of those that are adds something to the body’s genetic mix.