TITLE:
Assessing Ecotoxicity in Marine Environment Using Luminescent Microalgae: Where Are We At?
AUTHORS:
Sophie Sanchez-Ferandin
KEYWORDS:
Ecotoxicity, Microalgae, Bioluminescence, Luciferase, Gene Reporter System
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.6 No.15,
September
30,
2015
ABSTRACT: Nowadays, microalgae are particularly used to assess the environmental impact of contaminants
in aquatic systems. Naturally present in some algal species, bioluminescence is highly used in application
fields related to environmental monitoring. Bioluminescent dinoflagellates have played
a pivotal role in this domain. When exposed to heavy metals or toxic organic compounds, bioluminescent
dinoflagellates have the capacity to decrease light emission. In addition, new molecular
tools allow the possibility to produce genetically modified microorganisms which are able to perform
luminescence. Combined with the luciferase reporter gene, two main genetic constructions
can be employed. Activation of a specific inducible promoter induces the luminescence gene transcription
and this signal increases over time. Constitutive promoters result in a high basal expression
level of the reporter gene. During exposure to a potential toxic pollutant, the basal expression
level will decrease due to the toxic effect. Toxicity bioassays based on engineered luminescent
Chlorophyta microalgae are among the most sensitive tests and are an invaluable complement to
classical toxicity assays.