DegU co-ordinates multicellular behaviour exhibited by Bacillus subtilis.
Unicellular organisms use a variety of mechanisms to co-ordinate activity within a community and accomplish complex multicellular processes. Because some of the processes that are exhibited by one species can be physiologically incompatible, it raises the question of how entry into these different pathways is regulated. In the Gram-positive bacterium Bacillus subtilis, genetic competence, swarming motility, biofilm formation, complex colony architecture and protease production are all regulated by the response regulator DegU. DegU appears to integrate environmental signals and co-ordinate multicellular behaviours that are subsequently manifested at different levels of DegU phosphorylation. Data are presented which indicate that: (i) swarming motility is activated by very low levels of DegU approximately P that can be generated independently from its cognate sensor kinase DegS; (ii) complex colony architecture is activated by low levels of DegU approximately P that are produced in a DegS-dependent manner to activate transcription of yvcA, a novel gene required for complex colony architecture; and (iii) high levels of DegU approximately P inhibit complex colony architecture and swarming motility but are required prior to the activation of exoprotease production. A model is proposed to explain why such a system may have evolved within B. subtilis to control these multicellular processes through a single regulator.
Verhamme
Daniël T
DT
Division of Environmental and Applied Biology, College of Life Sciences, MSI/WTB/JBC Complex, University of Dundee, Dundee DD1 4EH, UK.
Kiley
Taryn B
TB
Stanley-Wall
Nicola R
NR
D001412:Bacillus subtilis / Q000166:cytology* / Q000235:genetics / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D020689:Exopeptidases / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics; D011401:Promoter Regions, Genetic; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; C066497:DegU protein, Bacteria; D014157:Transcription Factors; D020689:Exopeptidases