A Microorganism’s Friend
https://www.nature.com/articles/s41579-018-0004-5
Several studies in recent years point to just how much the human body is affected by the tiny organisms on us and in us. Their impact indicates that microorganisms could contribute more to our human functions than our own DNA. This growing interest in microorganisms motivates research about microorganism interaction. It turns out that microorganisms also have their very own social network among them. There are several methods of microorganism communication. Many of us learned in middle school science ecological symbiotic relationships, like how bees help flowers pollinate while flowers provide nectar. Likewise, microorganisms interact through symbiotic relationships. These include mutualism, where both organisms benefit, and parasitism, where one harms the other. We could label those relationships with positive and negative edges. However, there is a slew of various “-isms” among microbiota, which all cannot fit into binary categories, just as human relationships will exist on a spectrum.
Microorganisms maintain social networks because they are mostly auxotrophic, meaning that they cannot produce certain compounds on their own. But, through microbial exchange, they can acquire crucial vitamins and amino acids. However, microorganisms differ in their presentation of auxotrophy. Some organisms might lack a nutrient A, others might need a nutrient B, and others could be missing both A and B. Genes determine these assorted nutrient requirements across microorganism groups, and are therefore unchanging in a singular organism. As we humans make links to access more information and resources, microorganisms will choose their own “friends” based on their different auxotrophies to best receive the right nutrients. If the microorganisms correctly choose others to exchange nutrients with, they ensure a better exchange and can actually dominate over others. Microorganisms will also choose “friends” based on proximity. Understandably, it could getting amino acids all the way from one side of the petri dish to the other. Studies indicate that this spatiality drives microorganism partnership, similar to how many of our own friend groups are from the same location. In a way, we can see these microorganisms and their “friendships” as the oldest social network, long before humans arrived on the scene.