Abstract
Bacteria control multicellular behavioural responses, including biofilm formation and swarming motility, by integrating environmental cues through a complex regulatory network. Heterogeneous gene expression within an otherwise isogenic cell population that allows for differentiation of cell fate is an intriguing phenomenon that adds to the complexity of multicellular behaviour. This review focuses on recent data about how DegU, a pleiotropic response regulator, co-ordinates multicellular behaviour in Bacillus subtilis. We review studies that challenge the conventional understanding of the molecular mechanisms underpinning the DegU regulatory system and others that describe novel targets of DegU during activation of biofilm formation by B. subtilis. We also discuss a novel role for DegU in regulating multicellular processes in the food-borne pathogen Listeria monocytogenes.
Highlights
Bacteria control multicellular behavioural responses, including biofilm formation and swarming motility, by integrating environmental cues through a complex regulatory network
We review studies that challenge the conventional understanding of the molecular mechanisms underpinning the DegU regulatory system and others that describe novel targets of DegU during activation of biofilm formation by B. subtilis
During biofilm formation by B. subtilis, cells differentiate into specific subpopulations that become responsible for matrix production or sporulation (Chai et al, 2008; Vlamakis et al, 2008)
Summary
B. subtilis, like other bacterial species, is capable of manifesting different multicellular processes. Two-component signal transduction systems are the major family of signalling proteins by which bacteria sense and respond to changes in the environment They typically consist of a membrane-associated histidine kinase (DegS) and a cytoplasmic response regulator (DegU). The promoter regions contain multiple binding sites, with specific affinities, that result in the activation of transcription at low levels of signal perception but inhibition of transcription at high levels of signal. Given the central role that DegS and DegU have in coordinating multicellular responses in B. subtilis it is not surprising that the DegS–DegU regulatory system is finely controlled at the following three stages within the cell: degU transcription, DegU phosphorylation and DegU~P activity. The positive auto-regulation of degU transcription (Fig. 1) by DegU~P leads to the heterogeneous expression of degU within the population (Veening et al, 2008a, b)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
