#bacteria

The World's Largest Bacterium Can Grow up to 2 Centimeters LongWhen you think of bacteria, you assume that they can only be seen under a microscope. They are single-cell organisms, after all. But scientists have discovered one that can can grow up to two centimeters (.78 inches) long! Yes, that is still only one cell. Thiomargarita magnifica is not the first known bacteria that can be seen with the naked eye, but it is the biggest so far, ten times bigger than scientists thought possible. But that's not all that makes T. magnifica special.Most bacteria contain DNA free-floating in the cell, while higher orders of life package and protect their DNA in a cell nucleus. But T. magnifica separates its DNA in a sac, separate from a water-filled sac that it uses to take in nutrients. That difference blurs the line between bacteria and other single-cell microbes (prokaryotes) and multi-cellular species (eukaryotes).We may have to redefine classifications due to this new discovery. Read about Thiomargarita magnifica and how it was discovered at Science. #bacteria #Thiomargaritamagnifica #DNA

Bacteria are Evolving to Consume PlasticThe earth has a way of changing and adapting to new conditions over millions of years. New species arise, fill ecological niches, and then evolve again when conditions change. There was a time in the earth's ancient past that an adaptation in trees caused pollution in the form of too much lignin. Eventually, a type of microorganism evolved that ate lignin and solved the problem, although it took many millions of years. Today the pollution is human-driven, and the world has too much plastic. Will something evolve that eats plastic? That's already happened. Scientist discovered a new bacterium they named Ideonella sakaiensis near a plastic recycling facility in Japan. I. sakaiensis manufactures an enzyme that breaks down the plastic called polyethylene terephthalate (PET) into organic molecules it can consume. Other bacteria with such talents have been identified since then. But we don't have tens of million of years to dispose of plastic. Mother Nature has all the time in the world, but in order to preserve life as we know it, scientists are growing these plastic-eating bacteria and boosting their PETase, which is what the novel enzyme was named. While we still need to reduce our plastic waste, having microbes that decompose it can't hurt. Or can it? When we encourage any species to evolve and thrive, we don't know what the long-term consequences will be. Read more about this research at Real Clear Science. (Image credit: Dying Regime) #bacteria #plastic #evolution

A Cancer-Quashing Microbe Emerges from the DeepWhile we often think of them as life-threatening, bacteria are so numerous and so varied that these microbes have saved countless people from death. Through several decades in the 20th century, scientists harnessed bacteria to produce natural but specific chemical compounds that could be used to prevent and/or treat disease, particularly the useful class called Actinomycetes. The more exotic the bacteria's habitat, the more specific these chemicals turned out to be. But it's hard to find new bacteria. Oceanographer Paul Jensen and chemist William Fenical teamed up to look into the ocean depths for marine bacteria that were different from their landlocked cousins, in order to study their potentially useful chemical talents.At the time, says Fenical, the consensus among pharmaceutical microbiologists was that actinomycetes lived only on land, and therefore “nothing was important in the oceans.” But Fenical suspected that a sampling bias drove that conclusion, and in June 1989, he and Jensen traveled to the Bahamas to see for themselves, collecting vials of ocean-floor sediment from 15 different locations at depths of up to 33 meters. Back at the lab, it didn’t take long for the two scientists to prove the naysayers wrong. When they cultured their samples, they found 289 separate actinomycete colonies. Some of these bacteria, members of a new genus that they later named Salinispora, had never been documented on land. Moreover, they were most abundant in the deeper samples, suggesting that they hadn’t simply washed into the ocean with terrestrial runoff. And then there was the kicker: Salinispora grew only in salt water.Working with a team of colleagues, Jensen eventually identified two different species of Salinispora bacteria from the Bahamian samples, both of which produced unique active compounds. One of these species, S. tropica, made a molecule that would change the course of their careers. When Fenical tested it on a line of difficult-to-kill human colon cancer cells, the compound passed with flying colors. He then sent it to labs at the National Cancer Institute to be tested against a panel of 60 different cancer cells. The results were exactly what Jensen and Fenical wanted to see: the compound, which they named salinosporamide A, was especially active against some cancer cell lines, but not others.“You want that selectivity, because if it kills all cancer cells equally, then it’s probably also going to equally kill noncancerous cells,” Jensen explains. It seemed they had the makings of a viable drug on their hands: a compound that could target a tumor without killing the person it afflicted.Read how salinosporamide A, also called marizomib, went from a bacterial product to a life-saving medicine at Hakai magazine. The article is also a look into how networks of scientists in the field, the lab, and in patient care have to work together to advance medical science. -via Real Clear Science#medicine #bacteria #cancer

Why People Who Brush Still Get Cavities Like my parents, I've always drank coffee and tea with no sugar instead of soda pop, and brushed my teeth religiously. And like my parents, I have endured a lifetime of dental repair. It doesn't seem fair, especially when I encounter people who are haphazard about dental hygiene but never get cavities. It appears that there are more factors at play in our mouths, specifically streptococcus mutans.   Increasingly, scientists are thinking of cavities as a microbiome problem. The advice you got as a kid — brush your teeth, floss, eat less candy — is still important. But it’s becoming more clear that the types of bacteria inhabiting your mouth matter, too. Some people do all the oral hygiene stuff right and still get cavities because of the bacteria living in their mouths. Which presents a question: If the types of bacteria in your mouth can make you more prone to cavities, could you fix your teeth by getting different bacteria?Getting different bacteria leads one to think of a saliva transplant, but that idea comes with a whole other set of questions. Read what we know so far about how the microbiome in our mouths affects tooth decay at FiveThirtyEight. -via Damn Interesting(Image credit: RosarioVanTulpe) #microbiome #cavity #toothdecay #bacteria

The Persistence of Bacteria In ConcreteConcrete is the most common building material in the world because of its great durability. However, just like all materials, concrete structures deteriorate in quality through time, and because many structures all over the world are made of concrete, there is a growing need for concrete maintenance and repair.Bacteria thrive best in a warm and moist environment. Knowing this, it would be extremely difficult for bacteria to thrive in concrete. In fact, it might just be the worst possible environment for bacteria, as concrete is hard, dry, and salty. Yet, there are bacteria which can survive inside concrete. Some could even provide “biorepair” to the concrete. Scientists hope to use bacteria someday as a new method for providing concrete maintenance.#Concrete #Bacteria #ConcreteMaintenance #Biorepair(Image Credit: Kathy F. Atkinson and Anders Kiledal/ University of Delaware)

Museum Used Flesh-Eating Bacteria to Clean Michelangelo's Statues Because They're Full of Human CorpseArt historians have long noticed that marble sculptures by Michelangelo on the tomb of Duke Alessandro de Medici were staining badly, but it was only in 2019 that they discovered the gruesome reason: the improperly embalmed corpse within was leaking.Thankfully, science has the solution in form of flesh-eating bacteria:Anna Rosa Sprocati, a biologist at the Italian National Agency for New Technologies, hand-picked from her catalog of more than 1,000 bacteria to test against the stains. They had successes and failures, with some of the bacteria eating not just the human remains, but the delicate Carrera marble, too. But the chapel's museum believed that bacteria would be more effective than harsh chemicals or abrasives.Sprocati's all-female team picked the eight most promising bacteria and tested them on a gridded section behind the altar of the church. The ones that worked were then put on the tomb of Giuliano di Lorenzo, specifically the statues of Night and Day. The bacteria successfully cleaned Night's hair and eyes of accumulated residue.Image: eos1/Wikimedia Commons#flesheatingbacteria #Michelangelo #Medici #marblestatue #bacteria