Researchers found bacterial cells so large they are easily visible to the naked eye, challenging ideas about how large microbes can get.
In a Caribbean mangrove forest, scientists have discovered a species of bacteria that grows to the size and shape of a human eyelash.
These cells are the largest bacteria ever observed, thousands of times bigger than more familiar bacteria such as Escherichia coli. “It would be like meeting another human the size of Mount Everest,” said Jean-Marie Volland, a microbiologist at the Joint Genome Institute in Berkeley, Calif.
Dr. Volland and his colleagues published their study of the bacteria, called Thiomargarita magnifica, on Thursday in the journal Science.
Scientists once thought bacteria were too simple to produce big cells. But Thiomargarita magnifica turns out to be remarkably complex. With most of the bacterial world yet to be explored, it is entirely possible that even bigger, even more complex bacteria are waiting to be discovered.
It has been about 350 years since the Dutch lens grinder Antonie van Leeuwenhoek discovered bacteria by scraping his teeth. When he put the dental plaque under a primitive microscope, he was astonished to see single-celled organisms swimming about. For the next three centuries, scientists found many more kinds of bacteria, all of which were invisible to the naked eye. An E. coli cell, for example, measures about two microns, or under a ten-thousandth of an inch.