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Perspective

Life, Death, Differentiation, and the Multicellularity of Bacteria

  • Susan M. Rosenberg mail

    smr@bcm.edu

    Affiliation: Departments of Molecular and Human Genetics, Biochemistry and Molecular Biology, Molecular Virology and Microbiology, and the Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, Texas, United States of America

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  • Published: March 13, 2009
  • DOI: 10.1371/journal.pgen.1000418

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Behavior of Bacteria and Systems Science: New Isomorphism.

Posted by janecka on 29 Mar 2009 at 20:42 GMT

Many of the behaviors of bacteria that you described in your article (*) are quite congruous with systems science principles. Here are some of the main correlates:
The observed appearance of “multicellular” behavior of individual cells for a group benefit is analogous to the systems science principle of each system component optimizing the whole system instead of maximizing self.
The bacterial cell–cell communication imparting higher functionality to groups (like production of light, or attacking a host with toxin proteins) indicates compliance with system’s principle of emergence where the whole is greater than the sum of its parts.
The approach to risk by bacteria is especially relevant to the current breakdown of the financial system. You mentioned that bacteria differentiate subpopulations that take risks, while the remaining cells stay aloof, hedging the clone's bets—a process called bistability. The wisdom of biology is awe aspiring as bacteria innately understand that being too big to fail is not really a survivable option in the long-term. The Dynamic Systems Model (**) differentiates functional benefits, limits and the risks of the zone of chaos.
The capacity of small cell subpopulations of starving bacteria of many species take up foreign DNA, thus altering their genomes, indicates the existence of a high degree of self-adaptation to the environment as well as a well-functioning semipermeable system’s boundary.
The fact that many bacteria continuously differentiate small subpopulations of temporarily growth-impaired “persister” cells that will lose in a race to colonize new territory rapidly, but can survive a transient blast of antibiotics that will kill their rapidly growing siblings, ensuring some survivors in a clone, points to the evolutionary capabilities of a well-designed biologic system. The “persister” cells find themselves in the entropy-susceptible zone of order (**) while the rapidly growing sibling cells are in the outer edge of the zone of chaos where randomness is prevalent and risk of sudden catastrophic event is high; this clustering of cell functionality in different zones of the system’s model, assures the survival of the entire system.
The differentiation of a cell subpopulation slated for programmed cell death is a normal process of system cycle resetting which either totally ends or moves to a different singularity of oscillation. Biologic systems are open systems with the need to maintain the system-essential gradient and velocity of energy and info; as part of this process, discarding must happen as part of acquiring.
As systems science continues to evolve, the observed isomorphic resonance with biology should continue. The sophisticated and highly adaptable group behavior of individual bacteria, described in your Perspective, is a valuable step in that direction.
*Rosenberg SM: Life, Death, Differentiation, and the Multicellularity of Bacteria. PLoS Genet 5(3): e1000418. doi:10.1371/journal.pgen.1000418 http://www.plosgenetics.o...
** Janecka IP: Cancer control through principles of systems science, complexity, and chaos theory: A model. Int J Med Sci 2007; 4:164-173. http://www.medsci.org/v04...

No competing interests declared.