Scientists have discovered the world’s largest bacteria in a Caribbean mangrove swamp.
Most bacteria are microscopic, but this one is so large that you can see it with the naked eye†
The thin white filament, about the size of a human eyelash, is “by far the largest bacterium known to date,” said Jean-Marie Volland, a researcher. marine biologist at Lawrence Berkeley National Laboratory and co-authored a paper announcing the discovery Thursday in the journal Science†
Olivier Gros, a co-author and biologist at the University of the French Indies and Guyana, found the first example of this bacterium — called Thiomargarita magnifica, or “beautiful sulfur pearl” — clinging to submerged mangrove leaves in the Guadeloupe archipelago in 2009. .
But he didn’t immediately know it was a bacterium because of its surprisingly large size — these bacteria reach an average length of 0.9 centimeters. Only later genetic analysis revealed that the organism was a single bacterial cell.
“It’s an amazing discovery,” said Petra Levin, a microbiologist at Washington University in St. Louis, who was not involved in the study. “It begs the question of how many of these giant bacteria there are — and reminds us that we should never, ever underestimate bacteria.”
Gros also found the bacteria attached to oyster shellsrocks and glass bottles in the swamp.
Scientists have not yet managed to grow it in lab culture, but the researchers say the cell has a structure that is unusual for bacteria. One key difference: it has a large central compartment, or vacuole, that allows some cell functions to take place in it controlled environment rather than throughout the cell.
“The acquisition of this large central vacuole definitely helps a cell evade physical limitations… about how big a cell can be,” said Manuel Campos, a biologist at the French National Center for Scientific Research, who was not involved in the study. research. †
The researchers said they’re not sure why the bacterium is so large, but study co-author Volland hypothesized it could be an adaptation to prevent it from being eaten by smaller organisms.