“Most bacteria have microscopic cells that measure around 2 microns in length,” explained study lead author Jean-Marie Volland, a microbiologist at Lawrence Berkeley National Laboratory (Berkeley Lab).

There are some bacteria that can measure several hundred micrometers, but they are within the theoretical limit for how large they can grow. T magnifies, however, it is well above this limit. In comparison to most bacteria, it would be comparable to meeting another human as tall as Mount Everest.'

In addition to its enormous size, T. Magnifica has also surprised scientists with the unusual way that it stores its DNA. Unlike most bacteria, this bacterium's DNA was found inside compartments similar to those found in plants and animals.

The membrane-bound compartments represent a new type of bacterial organelle, which we call Pepin's, explained Dr. Volland. 'Until now, we believed that DNA is only packaged inside organelles in eukaryotic cells. As a result, it is an example of a bacterium that has evolved to a higher level of complexity.'

Similar to its genus-mates, T Magnifica contains a number of genes involved in sulfur oxidation and carbon fixation. In contrast to its relatives, this bacterium lacks most genes associated with nitrate metabolism, suggesting a sedentary lifestyle that makes it impossible to infect humans.

An estimated 25% of its genome is devoted to secondary metabolism, explained Tanja Woyke, an expert in single-cell genomics at Berkeley Lab. The genes may contain bioactive compounds, which may explain why we didn't find bacteria on the outside of the cell.

These genes make up a significant portion of its genome, which consists of about 12 million base pairs. It's not unheard of in bacteria but it's within the upper range. The genome of each cell contains more than half a million copies, or three trillion base pairs, which is a thousand times bigger than the human genome.”

There is still work to be done to better understand the world's largest bacterium's role in the ecosystem in which it lives, and how it evolved to attain its enormous size and strange genetic features.

'This study has opened our eyes to the diversity of microbes that have been unexplored,' said Shailesh Date, senior author of the study and associate professor of epidemiology and biostatistics at the University of California, San Francisco.

'We're just scratching the surface of things, and who knows what interesting discoveries await us. In addition to offering insights into the tree of life, the study of biological complexity may eventually lead to the development of new physiologies and biochemistry.'Original source: This news was published by earth.