Germs usually live their tiny lives in an invisible realm, but now scientists have discovered a marvel the size of a human eyebrow. The new findings are “the largest bacterium known to date,” Jean-Marie said. The team for researchers from Lawrence Berkeley National Laboratory and the Comprehensive Research Laboratory discovered these bacteria. These germs are 5,000 times larger than most germs. ” He added: “To see things the same way, it is quite common for people to meet another person as tall as Mount Everest.”The smoker, about one inch [1 cm] in diameter, somehow attaches itself to the damp leaves of the Caribbean mangrove swamp. But laboratory tests revealed that they did not ‘have the essential properties of plant or animal cells, and genetic analysis quickly revealed their true nature. They are related to other bacteria that live in sulfur and grow into large ones – but not the big ones.
Now called Thiomargarita magnifica, these bacteria have not yet been developed in the laboratory, so much about their way of life remains unclear – including what benefits they get from their underwater environment by growing to such a large size they live on oxidizing sulfur, and are 50 times larger than any other known bacteria.
Hiding in the decaying leaves of the Caribbean Guadeloupe mangroves in the Caribbean lives a rare species of cord. These tiny insect-like insects, which grow to about an inch in length, are the largest germs in a single cell. Biologist Olivier Gros discovered the virus in 2009 while studying mangroves in Guadeloupe, where he works at the University of Antilles, the French West Indies. “At first, I thought it was something like a fungus or a virus, but eukaryote, maybe,” Gros said. Unlike bacteria and archaea, which are simple microorganisms, eukaryotes that combine animals and plants are complex cells that contain nucleus and organelles such as mitochondria.
Returning to his research facility at Pointe-à-Pitre in Guadeloupe, Gros examined his microscope. It was then that he realized he wasn’t looking for eukaryote – and that he had found something special. In 2018, marine biologist Jean-Marie Volland at the Lawrence Berkeley National Laboratory in California, examined bacteria more closely using a series of mechanisms, including electron microscopy transmission and a thought process called fluorescence in situ hybridization. In this way, he helped ensure that it was a single cell.
Thiomargarita magnifica
There are other whoppers in the Thiomargarita bacterium family, but the next largest is only 750 micrometres in length. Some fiber-like organisms are found in mangroves, but all consist of tens or even hundreds of cells. “What’s so different about T. magnifica that all the fibers, among the longest fibers in a stalk, are just one cell, ”says Volland.The key to the bacterium is its vacuole – a water-repellent, fluid-filled membrane. At the edges of these structures are structures bound by membranes, which the authors call pepin and describe them as organisms commonly found in eukaryotic cells. T magnifica is remarkable for its size. In some viruses, genes float freely within a cell, usually in the form of a single circular chromosome. In T. magnifica, the team found that genetic information was stored in hundreds of thousands of these pepins. Each of these contains DNA and ribosomes, molecular machines that translate instructions from DNA to make proteins. Pepins collectively hold up to 700,000 copies of the genome.
In addition to the old challenging ideas about the possible size, each of these organisms arranges its interior in an unusual way. package type. This is similar to what is done to complex cell types, such as those that make up plants and animals. Volland warns that this does not mean that these viruses are some kind of “non-existent link” between the simplest and most complex forms of life, citing “just an interesting example of a bacterium that has transformed a high level of complexity.”
However, the discovery of this internal organism, along with its astonishing size, makes this a “truly remarkable discovery,” according to Thijs Ettema, a microbiologist at Wageningen University & Research who was not part of this research team.”Researchers have discovered a real ‘microbial monster’,” Ettema said in an email. “Their work emphasizes that the microbial world continues to amaze us!” These germs cannot even be properly named microbes, because germs by definition are invisible, notes Petra Anne Levin of Washington University in St. Louis, who wrote the report accompanying the article new report. Furthermore, although many germs reproduce separately into two identical cells, these long, filamentous creatures seem to reproduce by sprouting from one small piece that may eventually float and continue to make something new.
And even though these insects are so large that hundreds of thousands of tiny bacteria can invade their outer space, researchers found that these areas look clean, suggesting that these germs may release a certain type of antibiotic to repel younger relatives. Discovering the virus “has really opened our eyes to the vast variety of untested insects that exist,” says Shailesh Date of the University of California, San Francisco, with the Comprehensive Systems Research Laboratory. There are many questions left.
Among them are whether the mangrove habitat, which has high levels of sulfur molecules and sulfur-eating bacteria, is important for the presence of this virus. And pepins themselves need to be looked at to determine if they all contain the same mixture of genes, ribosomes, and proteins. “We have not yet followed each pepin – we have followed the whole cell, which contains hundreds of thousands of pepins,” Volland said. In particular, researchers do not know that each pepin contains one copy of the genome, or more than one.
Now as T. magnifica has been discovered, Gros expects other teams to go in search of even bigger viruses – which may be hidden, he says. Petra Levin at the University of Washington in St. Louis, Missouri, says the discovery challenges the common sense that viruses have a lower limit than eukaryotic cells. “Maybe there is an extra limit on cell size at some point, but I don’t think it will differ from bacteria or archaea or eukaryote.” “We should not underestimate the value of evolution, for we cannot predict where it will go” Says Kevin. “I wouldn’t have guessed that this thing exists, but now that I see it, I see the concept of evolution so far.
Source Journal Reference: Katharine Sanderson, Largest bacterium ever found is surprisingly complex, nature News (2022), https://www.nature.com/articles/d41586-022-01757-1
