I used to be fascinated by invertebrate marine animals, but lately my affections have turned to bacteria and how they affect their environments—usually in humans, but my attention was caught recently by news about bacteria living in the top 1/500th of an inch of the ocean.
New research by a Canadian scientist is revealing more about the bacteria that live in the top 60 microns of the oceans. Globs of carbohydrates—jelly, the researchers called it—released by phytoplankton in the lower inches of water float up to the surface and form an incredibly thin layer. The layer is remarkably intact, surviving up to surface wind speeds of 16-18 knots. As it buffers the environment below from surface turbulence, it nurtures a microbial colony that is dominated by organisms commonly found in biofilms. Biofilms are found in many many places, and seem to have roles both in the origin of chronic diseases like recurrent ear infections and tooth decay, as well as in the protection of human health, such as in the reserves of good bacteria in our appendixes. They also form the slippery coating on rocks in streams, tiles in shower stalls, and the inside of sewer pipes. And my favorite zoogleal mat—the kombucha culture—is a variety of biofilm as well.
There is something amazing and terrifying to me about bacteria and other microorganisms ganging together to form large-scale structures with differentiated functions and microstructures like channels to shunt nutrients around in the film.
In the case of the microbial colonies at the surface of the ocean, we may find them intensely involved in the processing of contaminants in the ocean and in the absorption of carbon dioxide from the atmosphere. Understanding the health of the oceans and how they affect the health of the whole Earth must involve an understanding of this minutely thin surface layer—as everything coming into and going out of the ocean passes through this layer!
How strange that global warming, chronic ear infections, and kombucha share this connection. I’m starting to read a review paper from 2007 in the journal Microbiology to understand a bit more about biofilms – given my interests I think I’m going to keep hearing about them through the years!