Morphological and functional asymmetry in alpha-proteobacteria.
The release of an increasing number of complete bacterial genomic sequences allows the evolutionary analysis of processes such as regulatory networks. CtrA is a response regulator of the OmpR subfamily, belonging to a complex regulatory network in the dimorphic bacterium Caulobacter crescentus. It coordinates the cell cycle with an asymmetric division, which is part of the adaptation of Caulobacter to poor-nutrient environments. CtrA is only found in alpha-proteobacteria, a group of bacteria encompassing genera with very distinct lifestyles, including host-associated bacteria. Analyses of CtrA regulatory networks and morphological examinations of some alpha-proteobacteria are presented. Our observations suggest that the core of the CtrA regulation network is conserved and that alpha-proteobacteria divide asymmetrically. We propose that the two daughter cells might be differentiated bacteria, each one displaying specific functions.
Unité de Recherche en Biologie Moléculaire (URBM), University of Namur, 61 rue de Bruxelles, B-5000 Namur, Belgium.
Régis
R
Hallez
Anne-Flore
AF
Bellefontaine
Jean-Jacques
JJ
Letesson
Xavier
X
De Bolle
D001426:Bacterial Proteins / Q000502:physiology*; D001665:Binding Sites; D016935:Caulobacter crescentus / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D002453:Cell Cycle / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D014157:Transcription Factors / Q000502:physiology*
D001426:Bacterial Proteins; C097706:CtrA protein, Caulobacter; D004268:DNA-Binding Proteins; D014157:Transcription Factors