Bacteria Build Interconnected Structures Just Like We Build Cities


We call bacterial cities biofilms. Dental plaque is such a biofilm. But we should know a bit more about this biofilm before we indulge ourselves next time and skip brushing our teeth. Oral flora is consistent with different types of bacteria. Some of them are needed to keep things in order and healthy. The bad guy that causes plaque is Streptococcus mutans. It gets hep from other anaerobes, but it is Streptococcus mutans that’s in command.

A new study performed thorough surveillance of Streptococcus mutans’ behavior and discovered that it isn’t much different than gregarious human conduct. Even if, surprisingly, only 40% of the bacteria stay alive and flourish, the rest of it getting lost in loneliness or being used by the strongest, this 40% manages to build an entire universe in our mouth.

How Bacteria Build Interconnected Structures

About 80 to 90% of the weight of plaque is water. The dry weight is split into 70% bacteria and 30% polysaccharides and glycoproteins. It is a messy and stinky universe, but they work hard for it. “And what we see is that, remarkably, the spatial and structural features of their growth are analogous to what we see in urbanization,” says Hyun Koo from the University of Pennsylvania.

To understand better how they do it, we must realize how biofilm works. A biofilm is an environment based on cross-feeding. It means that one species lives off what another species produces. They depend on one another. They form little colonies in different areas with the ultimate goal of merging all. They need their neighbor to thrive, so they mutually endorse their efforts.

Streptococcus mutans build without competing with one another. Rooms, houses, districts, cities, all made of extracellular polymeric substances. These are natural polymers secreted by themselves into their environment. Yeah, it is their environment, too, not just our mouth!
So, how does it feel to know you are subject to microbial exploitation?