Rhythm of Prosperity

In human society, cooperation and competition are among the most important elements that drive social development. This is likely true for any community-based organization. How do we strike a balance between these two factors to maximize the benefit of the community as a whole? This question has intrigued a wide range of researchers, including biologists, economists, and sociologists. By looking into a relatively simple community, scientists now unveil the rhythm of prosperity for Bacillus subtilis biofilms and decode the intricate metabolic regulation behind the scene (Liu et al., 2015). The story started with the observation that after growing to a certain size, the biofilm expansion became oscillated due to the limitation in glutamine supply. Interestingly, only the cells in the periphery contributed to the periodic expansion, and these cells were exactly the ones exposed to plenty of glutamate in the media, an essential component for glutamine synthesis. Naturally, the other key component for glutamine synthesis, ammonium, came to mind. As it turned out, the bacterial cells in the interior were responsible for feeding the peripheral cells ammonium, thereby sustaining the biofilm growth while they themselves remained nonproliferating.