aMakes only plush stature thiomargarita magnifica Something very special: the creature is well over a centimeter long and is visible to the naked eye. It certainly sounds remarkable because the life form researchers working with French biologist Jean-Marie Woland of the University of California at Berkeley discovered in the mangrove swamps of Guadeloupe is a unicellular organism. And this is remarkable, but also not completely different from the usual. There are many marine protozoa that are anything but microbes in the sense of microscopic life, such as bladderwort algae. wallonia ventricosaAlso called “cellar’s eyeball” in English, whose cells can reach up to four centimeters in diameter.
But thiomargarita magnifica A cell is not an algae or any other higher organism in the biological sense, but a bacterium. The largest type of bacteria known to date, the sulfur bacteria Thiomargarita Namibiansis, on average 180 micrometers long, isolated specimens reach an impressive 750 micrometers, or 0.75 millimeters, for which you’d need at least a magnifying glass as a person with normal vision. As the name suggests, is T. magnifica It is now related to the record holder, but grows to 50 times its size and is larger than some animals, for example nematodes or fruit flies. Most bacteria, on the other hand, do not reach more than a few micrometres. this tower T. magnifica From five thousand times. “It’s like meeting a man the size of Mount Everest,” says Jean-Marie Woland.
spirit of nitrate
come to know T. magnifica As an unusual accumulation of long white fibers on the surface of rotting leaves in a mangrove swamp of a Caribbean island belonging to France. as Woland and co-authors Report now in Science, the macroscopic microbe lives by “inhaling” the nitrate and oxidizing sulfur in the process. The name Thiomargarita literally means “sulfur pearl” and comes from the sulfur granules that members of this genus carry in their cytoplasm.
Giant bacilli store nitrate in a giant sac, or vacuole, that occupies most of its cell, leaving only two to three microns of space under the cell membrane for sulfur granules and other organelles. so solves T. magnifica The problem of all giant protozoa: how to quickly transport molecules responsible for metabolism through the vast dimensions of the cell, when diffusion only allows biomolecules to move at a typical speed of one millimeter per hour.
Another trick of large protozoa is to distribute genetic material with instructions for the synthesis of important biomolecules throughout the cell. One T. magnificaThe cell contains an estimated 40,000 copies of its genetic information and takes the theory of the decentralized genome to an extreme, in that it packs each of these sets of DNA individually into its own vesicles, the so-called pepins. Petra Anne Levine from Washington University in St. Louis wrote in her publication science With comment, the data suggested that these pepins are the major sites for protein synthesis. “Also, the structure of pepins suggests that they function almost entirely like autonomous organelles within the cell.”
Charm, but also mystery thiomargarita magnifica However, it has a sheer, unexpected shape. This is similar to the questions posed by paleontologists to the giant herbivorous sauropods of the Jurassic and Cretaceous periods: why – through what evolutionary processes – these bacteria could or have become so large? AND: Have they reached the upper limit of what bacterial cells can be in terms of their dimensions and associated metabolic issues?
