Nooks and crannies in type VI secretion regulation.
Type VI secretion systems (T6SS) are macromolecular, transenvelope machines encoded within the genomes of most Gram-negative bacteria, including plant, animal, and human pathogens, as well as soil and environmental isolates. T6SS are involved in a broad variety of functions: from pathogenesis to biofilm formation and stress sensing. This large array of functions is reflected by a vast diversity of regulatory mechanisms: repression by histone-like proteins and regulation by quorum sensing, transcriptional factors, two-component systems, alternative sigma factors, or small regulatory RNAs. Finally, T6SS may be produced in an inactive state and are turned on through the action of a posttranslational cascade involving phosphorylation and subunit recruitment. The current data reviewed here highlight how T6SS have been integrated into existing regulatory networks and how the expression of the T6SS loci is precisely modulated to adapt T6SS production to the specific needs of individual bacteria.
Laboratoire d'Ingénierie des Systèmes Macromoléculaires, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, CNRS-UPR 9027, 31 chemin Joseph Aiguier, 13402 Marseille Cedex 20, France. cascales@ifr88.cnrs-mrs.fr
Christophe S
CS
Bernard
Yannick R
YR
Brunet
Erwan
E
Gueguen
Eric
E
Cascales
D001426:Bacterial Proteins / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D006090:Gram-Negative Bacteria / Q000502:physiology*; D005810:Multigene Family; D055571:Secretory Pathway / Q000502:physiology*
D001426:Bacterial Proteins