Natural transformation describes how some bacteria can incorporate exogenous DNA into their genome and acquire new traits. This phenomenon occurs in Vibrios and is induced by the biopolymer chitin. In Vibrios, TfoX is a primary regulator of natural transformation. The mechanisms underlying chitin-induced natural transformation and activation of TfoX in Vibrio fischeri remain unclear. This proje...

Ecotoxicity assessment using luminescent bacteria has been wildly used because it is rapid, sensitive and cost effective for screening water and wastewater quality. This mini-review focused on the application of Vibrio qinghaiensis sp. Q67 (abbreviated as “Q67”), a natural freshwater luminescent bacteria strain discovered in China. The characteristics of the bioassay using Q67 were firstly revi...

Vibrio fischeri belongs to the Vibrionaceae, a large family of marine gamma-proteobacteria that includes several dozen species known to engage in a diversity of beneficial or pathogenic interactions with animal tissue. Among the small number of pathogenic Vibrio species that cause human diseases are Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus, the only members of the Vibrion...

Quorum sensing (QS) describes the exchange of chemical signals in bacterial populations to adjust the bacterial phenotypes according to the density of bacterial cells. This serves to express phenotypes that are advantageous for the group and ensure bacterial survival. To do so, bacterial cells synthesize autoinducer (AI) molecules, release them to the environment, and take them up. Thereby, the...

Animals are typically colonized by diverse bacterial symbionts, many of which are commensal and, in numerous cases, even essential for their host's proper development and growth. In exchange, the host must supply a sufficient array and quantity of nutrients to support the proliferation and persistence of its microbial community. In this investigation, we have examined such a nutritional environ...

In a symbiosis, two or more evolutionarily distinct organisms communicate with one another in order to co-exist and co-adapt in their shared environment. The mutualistic symbiosis between the bioluminescent marine bacterium Vibrio fischeri and the Hawaiian squid Euprymna scolopes provides a model system that allows scientists to examine the mechanisms by which this communication occurs (McFall-...

Successful colonization of a eukaryotic host by a microbe involves complex microbe-microbe and microbe-host interactions. Previously, we identified in Vibrio fischeri a putative sensor kinase, RscS, required for initiating symbiotic colonization of its squid host Euprymna scolopes. Here, we analysed the role of rscS by isolating an allele, rscS1, with increased activity. Multicopy rscS1 activat...

Two-component signal transduction systems, composed of sensor kinase (SK) and response regulator (RR) proteins, allow bacterial cells to adapt to changes such as environmental flux or the presence of a host. RscS is an SK required for Vibrio fischeri to initiate a symbiotic partnership with the Hawaiian squid Euprymna scolopes, likely due to its role in controlling the symbiosis polysaccharide ...

CcdB(Vfi) from Vibrio fischeri is a member of the CcdB family of toxins that poison covalent gyrase-DNA complexes. In solution CcdB(Vfi) is a dimer that unfolds to the corresponding monomeric components in a two-state fashion. In the unfolded state, the monomer retains a partial secondary structure. This observation correlates well with the crystal and NMR structures of the protein, which show ...

Sandfly control measures were evaluated at the Da Barra Ranch, Lobato municipality, Paraná State, Brazil. The insects were captured with Falcão traps in houses, a cattle corral, and a forest area from July to November 1999 and from February to June 2000. In December 1999 and January 2000 the following measures were taken to decrease the sandfly density in peridomiciliary areas and domiciles: (i...