Quorum sensing in Vibrio controls carbon metabolism to optimize growth in changing environmental conditions.

Bacteria sense population density via the cell-cell communication system called quorum sensing (QS). The evolution of QS and its maintenance or loss in mixed bacterial communities is highly relevant to understanding how cell-cell signaling impacts bacterial fitness and competition, particularly under varying environmental conditions such as nutrient availability. We uncovered a phenomenon in which Vibrio cells grown in minimal medium optimize expression of the methionine and tetrahydrofolate (THF) synthesis genes via QS.

Bacterial quorum sensing controls carbon metabolism to optimize growth in changing environmental conditions.

Bacteria sense population density via the cell-cell communication system called quorum sensing (QS). Some QS-regulated phenotypes ( , secreted enzymes, chelators), are public goods exploitable by cells that stop producing them. We uncovered a phenomenon in which cells optimize expression of the methionine and tetrahydrofolate (THF) synthesis genes via QS.

The quorum-sensing systems of Vibrio campbellii DS40M4 and BB120 are genetically and functionally distinct.

Vibrio campbellii BB120 (previously classified as Vibrio harveyi) is a fundamental model strain for studying quorum sensing in vibrios. A phylogenetic evaluation of sequenced Vibrio strains in Genbank revealed that BB120 is closely related to the environmental isolate V. campbellii DS40M4.

Diversity in Natural Transformation Frequencies and Regulation across Species.

In species, chitin-induced natural transformation enables bacteria to take up DNA from the external environment and integrate it into their genome. Expression of the master competence regulator TfoX bypasses the need for chitin induction and drives expression of the genes required for competence in several species. Here, we show that TfoX expression in strains DS40M4 and NBRC 15631 enables high natural transformation frequencies.

Promoter Boundaries for the and Operons in Vibrio harveyi Defined by the Method Rapid Arbitrary PCR Insertion Libraries (RAIL).

Experimental studies of transcriptional regulation in bacteria require the ability to precisely measure changes in gene expression, often accomplished through the use of reporter genes. However, the boundaries of promoter sequences required for transcription are often unknown, thus complicating the construction of reporters and genetic analysis of transcriptional regulation. Here, we analyze reporter libraries to define the promoter boundaries of the bioluminescence operon and the osmotic stress operon in We describe a new method called apid rbitrary PCR nsertion ibraries (RAIL) that combines the power of arbitrary PCR and isothermal DNA assembly to rapidly clone promoter fragments of various lengths upstream of reporter genes to generate large libraries.