This paper describes the development of an automated Flow Injection analyzer for water toxicity assessment. The analyzer is validated by assessing the toxicity of heavy metal (Pb(2+), Hg(2+) and Cu(2+)) solutions. One hundred μL of a Vibrio fischeri suspension are injected in a carrier solution containing different heavy metal concentrations. Biosensor cells are mixed with the toxic carrier sol...

Nitric oxide (NO) is implicated in a wide range of biological processes, including innate immunity against pathogens, signal transduction and protection against oxidative stress. However, its possible roles in beneficial host-microbe associations are less well recognized. During the early stages of the squid-vibrio symbiosis, the bacterial symbiont Vibrio fischeri encounters host-derived NO, wh...

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...

To determine the abundance and species composition of luminous bacteria in the coastal waters of the southern Adriatic Sea (Otranto, Italy), samples were collected from three sites affected by different degrees of anthropogenic pollution. A total of 116 strains of marine luminous bacteria were isolated and subjected to phenotypic characterization, which included 36 biochemical tests. Numerical ...

Lipopolysaccharide molecules released by the bacteria Vibrio fischeri when it rotates its flagella prompts its host, the Hawaiian bobtail squid, to prepare for its arrival.

This study reports the first description and molecular characterization of naturally occurring, nonbioluminescent strains of Vibrio fischeri. These ‘dark’ V. fischeri strains remained non-bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (eig...

this study was carried out to investigate the occurrence of potentially pathogenic species of vibrio in sea water and estuarine environments of the caspian sea in the golestan province of iran. a total of 127 water samples from coastal waters as well as from river and estuaries were collected and analyzed by culture, during april and september 2001. following prompt centrifugation, the resuspen...

Vibrios are natural inhabitants of aquatic environments and form symbiotic or pathogenic relationships with eukaryotic hosts. Recent studies reveal that the ability of vibrios to form biofilms (i.e. matrix-enclosed, surface-associated communities) depends upon specific structural genes (flagella, pili and exopolysaccharide biosynthesis) and regulatory processes (two-component regulators, quorum...

This study reports the first description and molecular characterization of naturally occurring, non-bioluminescent strains of Vibrio fischeri. These 'dark' V. fischeri strains remained non-bioluminescent even after treatment with both autoinducer and aldehyde, substrate additions that typically maximize light production in dim strains of luminous bacteria. Surprisingly, the entire lux locus (ei...

Vibrio fischeri isolates from Euprymna scolopes are dim in culture but bright in the host. We found the luminescence of V. fischeri to be correlated with external osmolarity both in culture and in this symbiosis. Luminescence enhancement by osmolarity was independent of the lux promoter and unaffected by autoinducers or the level of lux expression, but the addition of an aldehyde substrate for ...