Bacterial solutions to multicellularity: a tale of biofilms, filaments and fruiting bodies

• Published in: Nature reviews. Microbiology Vol. 12; no. 2; pp. 115 - 124
• Main Authors: Claessen, Dennis, Rozen, Daniel E., Kuipers, Oscar P., Søgaard-Andersen, Lotte, van Wezel, Gilles P.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.02.2014; Nature Publishing Group
• Subjects: 631/326/2565/855; 631/326/41/2528; 631/326/41/2529; Apoptosis; Bacteria; Bacteria - cytology; Bacteria - growth & development; Bacterial Physiological Phenomena; Behavior; Biofilms; Biofilms - growth & development; Biological Evolution; Biological research; Biology; Biology, Experimental; Cell Division; Cell interaction; Cell Transdifferentiation; Cyanobacteria; Cytoskeleton; Infectious Diseases; Life Sciences; Medical Microbiology; Microbial colonies; Microbiology; Parasitology; Physiological aspects; review-article; Signal Transduction; Spores, Bacterial; Virology; Netherlands
• ISSN: 1740-1526; 1740-1534
• DOI: 10.1038/nrmicro3178

Key Points Bacterial multicellularity takes several phenotypically diverse forms and has independently evolved in different species. Simple bacterial multicellularity can rapidly evolve as a result of mutations that prevent cells from separating after division or that cause independent cells to co-aggregate. Hallmark features of bacterial multicellularity include morphological differentiation, programmed cell death and a well-defined and reproducible multicellular shape (known as patterning). The benefits of bacterial multicellularity include predation- and stress-resistance and improved resource acquisition and dispersal. Bacterial multicellular structures that arise via aggregation — for example, in Myxobacteria spp. — are susceptible to the emergence of cheater cells that exploit other cooperative cells. Experimental evolution offers exciting possibilities for understanding the mechanisms and dynamics of the de novo evolution of bacterial multicellularity under defined laboratory conditions. In this Review, van Wezel and colleagues discuss recent studies that have improved our understanding of the processes that lead to bacterial multicellularity. By considering phylogenetically diverse bacteria, the authors explore the evolutionary and ecological consequences of multicellular behaviour. Although bacteria frequently live as unicellular organisms, many spend at least part of their lives in complex communities, and some have adopted truly multicellular lifestyles and have abandoned unicellular growth. These transitions to multicellularity have occurred independently several times for various ecological reasons, resulting in a broad range of phenotypes. In this Review, we discuss the strategies that are used by bacteria to form and grow in multicellular structures that have hallmark features of multicellularity, including morphological differentiation, programmed cell death and patterning. In addition, we examine the evolutionary and ecological factors that lead to the wide range of coordinated multicellular behaviours that are observed in bacteria.