An image of the Martian surface from NASA’s Viking 2
To eke out even the barest subsistence on Mars, a living thing would have to adapt to a formidable set of environmental challenges: an arid, often extremely cold landscape with miniscule amounts of oxygen in the atmosphere and no organic matter to eat. During a recent foray into a similarly inhospitable part of our own planet, scientists have discovered several species of bacteria that hint at what life on Mars, if it exists, might look like. These microbes survive on minerals in the surrounding rocks—minerals also found in the Martian surface.
For the better part of a century, antibiotics have given doctors great powers to cure all sorts of bacterial infections. But due to bacteria’s nasty habit of evolving, along with widespread overuse of these drugs, disease-causing bacteria are evolving antibiotic resistance at an alarming rate, making it much harder, and at times impossible, to wipe them out. DARPA, the military’s research agency, is eyeing an innovative solution to the problem: Rather than struggling to make better antibiotics, ditch them altogether. It may be time to start killing bacteria a whole new way.
The bacterium Micavibrio aeruginosavorus (yellow), leeching
on a Pseudomonas aeruginosa bacterium (purple).
What’s the news: If bacteria had blood, the predatory microbe Micavibrio aeruginosavorus would essentially be a vampire: it subsists by hunting down other bugs, attaching to them, and sucking their life out. For the first time, researchers have sequenced the genome of this strange microorganism, which was first identified decades ago in sewage water. The sequence will help better understand the unique bacterium, which has potential to be used as a “living antibiotic” due to its ability to attack drug-resistant biofilms and its apparent fondness for dining on pathogens.
Israeli and German scientists recently took the plunge into the murky, salty Dead Sea, making what they say is the first scientific diving expedition there. Scouring the seafloor, they saw small freshwater springs—with mats of salt-loving, never-before-seen microorganisms coating the surface of nearby craters. In these waters—too salty for large animals, too rich in magnesium for many bacteria—seeing so much life was a surprise.
While floating in the Dead Sea is a popular tourist pastime, scuba-ing into its depths is a difficult and dangerous endeavor. Since the salty water is so buoyant, the divers had to carry 90 pounds each to weigh them down. Swallowing some of the salty water—a not-implausible occurrence during a dive—would make the larynx swell up, leading the diver to suffocate. If that weren’t enough, getting the water in your eyes would be painful at best, and potentially blinding. The scientists wore full face masks during their dive, and apparently weren’t scared off; they’re headed back down for a follow-up study in October.
The Centers for Disease Control and Prevention says at least 13 people have died as a result of a listeria outbreak linked to Colorado cantaloupes, making it the deadliest American case of food-borne illness in more than a decade, according to the Associated Press. The death toll could soon reach 16, health officials say, as investigators look into additional deaths in New Mexico, Kansas, and Wyoming. The CDC announced yesterday that 72 people in 18 states had been infected by several strains of Listeria monocytogenes. The bacterium has been traced to “Rocky Ford Cantaloupes” grown by Jensen Farms in Granada, Colo.
A cluster of 3.4 billion-year-old fossilized cells
What’s the News: Geologists have found fossils of microorganisms from 3.4 billion years ago, which may be the oldest fossils ever uncovered. Since these microbes date from a time when Earth’s atmosphere was still oxygen-free, astrobiologists could look for similarly structured microbes when searching for extraterrestrial life.
The European Food Safety Authority has released a scientific report on the deadly E. coli outbreak that has sickened more than 3,500 people and killed at least 44 in the last seven weeks, and the news is grim: the apparent source of the contamination, a shipment of fenugreek seeds from Egypt, has been scattered all across the continent, making recall tricky and new outbreaks likely until the seed packets reach their expiration date in three years. Maryn McKenna of Superbug expertly breaks down the report in all its chilling detail:
What’s the News: A massive outbreak of E. coli is spreading through Europe, with 17 people dead in the last two weeks and 1,500 people sickened in Germany alone, where the outbreak began. Authorities are still trying to figure out where the outbreak originated and how it can be treated.
What’s the News: Bacteria are everywhere—in us, on us, around us. But they’re also floating around in the atmosphere, and researchers cracking open hailstones have now discovered them at the core, lending credence to the theory that bacteria jump-start the atmospheric process of forming snow, hail, and rain as a way to hitch a ride down to Earth.
What’s the News: The bacterium that causes ulcers and some stomach cancers, Helicobacter pylori, could at least contribute to Parkinson’s disease, according to a new study in mice presented at a microbiology conference yesterday. Mice infected with H. pylori have shown Parkinson’s-like symptoms, building on earlier work that has suggested a link between the bacteria and Parkonson’s disease.