Social Bacteria- Structuring their Balanced Networks
Bacteria are known for being “selfish” organisms, only concerned with the progression of their individual genetic data. This article introduces a paradigm shift into how bacteria may actually work in “cohesive units”. Research at MIT indicates that certain bacteria may produce chemical compounds that can either destroy or inhibit the growth of bacterial populations in neighboring areas, while causing no harm to closely related populations. Resistance is given to similar bacterial strains, and antagonism towards those of minimal relation. It is difficult to analyze social interactions in some animal populations, especially in microorganisms. Yet this finding gives insight into further study of the social interactions within the realm of microbiology.
In the experiment, 185 related, yet distinct species of ocean bacteria in the family Vibrionaceae were observed within the same environment. About 35,000 interactions occurred amongst these organisms. The dynamic of these interactions varied based on different sensitivities towards antibiotics the bacteria release on one another. The bacteria that are unaffected by antibiotics are termed resistant. This resistance is an important avenue of research, especially in human health care.
In lecture, balanced networks were discussed from Chapter 5. The characterization of the balanced network can be applied to the social structure of these bacteria. Bacteria that are resistant and of close relation towards one another can be viewed as “mutual friends”, whereas not as closely related bacteria that release chemical toxins towards one another can be viewed as “mutual enemies”. Therefore, a balanced structure of different sets of bacteria is formed. The bacteria within these sets have positive interactions, yet between these sets are negative interactions. Every member of each node has a negative interaction (edge) towards every member of another node.
Thus, structural balance of positive and negative relationships can be seen even at the microbial level.
Source: Bacteria Show Complex Social Interactions. National Science Foundation. http://www.theepochtimes.com/n2/science/are-bacteria-social-microorganisms-289061.html. September 2012.