Biological complexity: more bacterial mat complexity (Introduction)

by David Turell , Friday, March 24, 2023, 23:33 (610 days ago) @ David Turell

A careful complete description:

https://www.scientificamerican.com/article/bacteria-gang-together-in-killer-biofilms-bu...

"Although individual bacteria are not visible to the naked eye, in this slime they form easily seen communities referred to as microbial mats, or “biofilms.” Through a microscope these films show remarkable three-dimensional structure, with microbes glued onto one another to form many levels of filaments, winding pathways and features resembling tiny towers. To me, they look like cities of slime, a pulsing metropolis with blocks and skyscrapers and streets that are busier than major avenues in Tokyo or New York.

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"There were early clues that bacteria within biofilms become fundamentally different from single cells. In 1998 researchers George A. O’Toole and Roberto Kolter demonstrated that biofilm formation by the soil bacterium Pseudomonas fluorescens required the synthesis of new proteins as well as the presence of 24 genes. Most of the genes were of unknown function, although some encoded proteins used for surface attachment, such as adhesins. The mystery genes suggested that becoming an attached cell meant taking on a novel bacterial physiology. Then, in 2002, my colleagues and I demonstrated that bacteria not only change on surface contact but keep transforming and adapting as the biofilm develops from just a few attached cells into a 3-D community, producing different sets of proteins at each stage. Further work showed that the proteins enable the transition from one biofilm stage to the next in a set sequence.

"These findings suggested that biofilms, like cities, are built brick by brick, with their construction following a master plan, one building phase and one city block at a time. Knowing how biofilms are built means that we have started to understand how to interfere with the master plan. In the laboratory, by adding chemicals that inhibit or enhance some of these proteins, we can stop biofilms at a particular developmental stage or even remodel them, making them revert to earlier stages. And some strategies are making their way to the clinic."

Comment: the article goes on to describe how to medical treat biofilm problems. My point is to show another example of bacterial actions. In this case banding together and supporting each other with new proteins helps them survive. Only bacteria have this capacity with the distinct ability to edit DNA as necessary. Living alone one-celled organisms must be ready and able to help themselves. Shapiro has shown this.