title: Thinking about bacterial populations as multicellular organisms.
abstract: It has been a decade since multicellularity was proposed as a general bacterial trait. Intercellular communication and multicellular coordination are now known to be widespread among prokaryotes and to affect multiple phenotypes. Many different classes of signaling molecules have been identified in both Gram-positive and Gram-negative species. Bacteria have sophisticated signal transduction networks for integrating intercellular signals with other information to make decisions about gene expression and cellular differentiation. Coordinated multicellular behavior can be observed in a variety of situations, including development of E. coli and B. subtilis colonies, swarming by Proteus and Serratia, and spatially organized interspecific metabolic cooperation in anaerobic bioreactor granules. Bacteria benefit from multicellular cooperation by using cellular division of labor, accessing resources that cannot effectively be utilized by single cells, collectively defending against antagonists, and optimizing population survival by differentiating into distinct cell types.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Chicago, Illinois 60637, USA. jsha@midway.uchicago.edu
authors.forename: J A
authors.initials: JA
authors.lastname: Shapiro
mesh_terms: D001412:Bacillus subtilis / Q000502:physiology; D001419:Bacteria / Q000166:cytology*; D001422:Bacterial Adhesion / Q000502:physiology; D018407:Bacterial Physiological Phenomena; D018441:Biofilms / Q000254:growth & development; D002455:Cell Division / Q000502:physiology; D004926:Escherichia coli / Q000502:physiology; D011511:Proteus / Q000502:physiology; D012705:Serratia / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology*; D013171:Spores, Bacterial / Q000502:physiology