#virus

#virus

The World's Deadliest VirusIf you were to guess the deadliest virus on earth, the odds are good that you'd guess rabies. The only reason you wouldn't is because you don't think of rabies as something that would affect you or someone you love. We've done a pretty good job in isolating people from the Rabies lyssa virus, by living indoors, having our animals vaccinated, and using vaccine treatment in the case of an animal bite. People who work with animals get rabies vaccines ahead of time. But lyssa is still a deadly virus because it works its way around your immune system. If it gets to the brain without treatment, you're a goner. And it's a horrible way to die. Kurzgesagt explains how the lyssa virus works inside one's body, whether that body belongs to a wild animal or a person. Despite the displayed length, this video is only nine minutes long.#virus #lyssa #rabies #Kurzgesagt   

Viruses Can Be Villains or HeroesMost of us are familiar with viruses as the tiny packets of DNA that can infect us and make us sick, and antibiotics can't help. Viruses such as smallpox, hepatitis, rabies, diphtheria, and COVID-19 are often quite deadly. But the world of viruses is much larger than those we've had bad experiences with. Viruses infect animals, plants, funguses, and even bacteria. The viruses, or bacteriophages, that invade bacteria cells keep them at manageable levels, whether in the oceans or in our digestive systems. This is an upside to viruses that equate to "the enemy of my enemy is my friend." Scientists are experimenting with bacteriophages that can attack cancer cells. But viruses have contributed to our ecosystem in other ways. There are two types of virus. Virulent phages are the ones that infect cells, replace their DNA, and use the cell to manufacture more virus. The other type are the temperate phages. These viruses will infect a cell and merge its DNA with that of the cell instead of evicting it. It may lie dormant and then become infectious years down the road. Or it may just create new combinations of DNA. In fact, temperate phages may be the crucial method of inserting genes that change existing life forms. Read how that happens at The Conversation. -via Damn Interesting#virus #phage #bacteriophage #DNA

What Happens When Two Different Respiratory Viruses Infect the Same CellViruses are microscopic packets of DNA that cannot reproduce on their own, so they infect living cells of species like ours. Once inside, they harness the cell's abilities to manufacture more virus. But what if that cell is already infected by a virus? Or two viruses invade at the same time? A study from the University of Glasgow set up human lung cells in a lab and gave it two different respiratory viruses to find out the results of this "co-infection." Research shows that up to 30% of infections may harbour more than one virus. What this means is that, at some point two different viruses are infecting the cells that line your nose or lungs.We know that co-infection can be important if we look at a process called “antigenic shift” in influenza viruses, which is basically caused by virus “sex”. This sometimes occurs when two different influenza strains meet up inside the same cell and exchange genes, allowing a new variant to emerge.Co-infection can create a predicament for viruses when you consider that they need to compete for the same resource: you. Some viruses appear to block other viruses, while some viruses seem to like each other. What is driving these positive and negative interactions during co-infections is unknown, but animal studies suggest that it could be critical in determining how sick you get.The experiment yielded some resulting virus particles that had DNA from both infectious viruses, what they called a "chimeric" virus. Read about the research and its implications at Real Clear Science. (Image credit: Yale Rosen) #virus #chimera #coinfection

Scientists Extracted 15,000-year-old Viruses, Most Previously Unknown to Man, From Tibetan Glacier IceScientists have extracted two ice core samples from a glacier at the Tibetan Plateau in China that contain viruses nearly 15,000 years old.Zhi-Ping Zhong, lead author of the virus study and researcher at The Ohio State University, said that as the glaciers formed gradually, they trapped dust, gases, as well as viruses in the ice. Studying the different layers of the ice cores help scientists learn about climate change, microbes, and viruses over the centuries.Previous studies conducted in Western China were limited in its ice core analysis. Now that they have new ice core samples, scientists discovered genetic codes for 33 viruses. Four of the viruses were previously known to science, but at least 28 of them were novel.Interestingly, about half of the viruses survived because they had gene sequences that made them thrive in extreme environments. "These viruses have signatures of genes that help them infect cells in cold environments - just surreal genetic signatures for how a virus is able to survive in extreme conditions," said professor Matthew Sullivan of Ohio State. "These are not easy signatures to pull out, and the method that Zhi-Ping developed to decontaminate the cores and to study microbes and viruses in ice could help us search for these genetic sequences in other extreme icy environments – Mars, for example, the moon, or closer to home in Earth’s Atacama Desert," he added.Image credit:Lonnie Thompson#virus #TibitanPlateua #WesternChina #ice #icecore #virology

Viruses Have a Novel Genetic Alphabet in Their DNAAsk any high school biology student how many bases our genetic material DNA has, and you'll get four as the answer: adenine (A), cytosine (C), guanine (G), and thymine (T).But in a series of new studies published in Science, three teams have identified dozens of viruses that has swapped one of the bases in their DNA for a novel one called 2-aminoadenine, later dubbed 'Z'.From Quanta Magazine:The Z base looks like a chemical modification of A; it’s an adenine nucleotide with an extra attachment. But that modest change allows Z to form a triple hydrogen bond with T, which is more stable than the double bond that holds together A-T....since the alterations were “at the deepest level of chemical organization,” [geneticist Philippe Marlière of the University of Evry in France] said, “my instinct told me this is not just an anecdote. This is a profound violation.”#DNA #virus #bacteriophage #biology #syntheticbiology #genetics