Giant Bacterium Unearthed Alters Perception of the Single-Celled Universe's Proportions
In a groundbreaking discovery, a team of researchers led by Olivier Gros, a mangrove biologist at the University of the French Antilles in Guadeloupe, have uncovered a new species of bacteria that defies traditional understandings of bacterial simplicity. Named Thiomargarita magnifica, this single-celled organism is more than a thousand times larger than a typical bacterium and carries more than 700,000 copies of its genetic blueprint, making it the largest bacterium ever discovered.
Before the discovery of Thiomargarita magnifica, the record for the largest bacterium was held by Thiomargarita namibiensis, discovered in 1999. However, Thiomargarita magnifica is more than 50 times larger, measuring approximately the size and shape of an eyelash.
The complexity of Thiomargarita magnifica is remarkable. Unlike most bacteria, which store their DNA in a single, unorganised region of the cell, Thiomargarita magnifica stores its DNA in tidy little packets called "pepins". These pepins are membrane-bound compartments that perform different functions, blurring the distinctions between bacterial and eukaryotic cells.
The structure of the pepins in Thiomargarita magnifica allows for more sophisticated control and greater complexity, further defying the previous understanding of bacterial simplicity. The complexity of Thiomargarita magnifica may help it overcome the predicted limits for bacterial cell size, as its structure allows for efficient nutrient absorption and metabolic processes.
Thiomargarita magnifica is longer than many multicellular animals such as fruit flies, yet it is a single bacterial cell. This discovery challenges the notion that bacterial cells cannot become very large due to basic physics and nutrient absorption requirements.
The discovery of Thiomargarita magnifica also suggests a possible explanation for the increasing size of eukaryotic genomes over time. As eukaryotic cells evolved from bacteria, they may have inherited the ability to organise their DNA into compartments like Thiomargarita magnifica, allowing for more efficient use of genetic material.
The next goal in the study of Thiomargarita magnifica is to grow it in a lab to further understand its biology and life cycle. Researchers are also working to understand its reproduction and maintenance of large genetic material in a lab setting.
The discovery of Thiomargarita magnifica illustrates the incredible diversity and intricate structural and genomic adaptations of bacteria. As research continues, we may uncover even more surprising discoveries about these microscopic organisms that play such a crucial role in our world.
