Chemoreceptor VfcA Mediates Amino Acid Chemotaxis in Vibrio fischeri

VfcA mediates amino acid chemotaxis in Vibrio fischeri 1 2

23 24 Flagellar motility and chemotaxis by Vibrio fischeri are important behaviors mediating 25 colonization of its mutualistic host, the Hawaiian bobtail squid. However, none of the 43 26 putative methyl-accepting chemotaxis proteins (MCPs) encoded in the V. fischeri genome has 27 been previously characterized. Using both an available transposon mutant collection and 28 directed mutagenesis, w...

Observing Chemotaxis in Vibrio fischeri Using Soft Agar Assays in an Undergraduate Microbiology Laboratory

Chemotaxis in Vibrio cholerae.

The ability of motile bacteria to swim toward or away from specific environmental stimuli, such as nutrients, oxygen, or light provides cells with a survival advantage, especially under nutrient-limiting conditions. This behavior, called chemotaxis, is mediated by the bacteria changing direction by briefly reversing the direction of rotation of the flagellar motors. A sophisticated signal trans...

Amino acid residues in LuxR critical for its mechanism of transcriptional activation during quorum sensing in Vibrio fischeri.

PCR-based site-directed mutagenesis has been used to generate 38 alanine-substitution mutations in the C-terminal 41 amino acid residues of LuxR. This region plays a critical role in the mechanism of LuxR-dependent transcriptional activation of the Vibrio fischeri lux operon during quorum sensing. The ability of the variant forms of LuxR to activate transcription of the lux operon was examined ...

Quorum regulation of luminescence in Vibrio fischeri.

Luminescence in Vibrio fischeri is controlled by a population density-responsive regulatory mechanism called quorum sensing. Elements of the mechanism include: LuxI, an acyl-homoserine lactone (acyl-HSL) synthase that directs synthesis of the diffusible signal molecule, 3-oxo-hexanoyl-HSL (V. fischeri autoinducer-1, VAI-1); LuxR, a transcriptional activator protein necessary for response to VAI...