Objectives

The Laboratory of Ecotoxicology, Genomics and Evolution (LEGE) is a research unit that includes scientists and graduate and post-graduate students with a multidisciplinary background (biologists, biochemists, chemists, pharmaceuticals, environmental sciences, computer sciences, among others). Our main goal is to understand the ecotoxicological impact of natural toxins and other emergent organic compounds from the molecular reaction to the ecosystem response. By using evolutionary genomics we want to understand how organisms develop their organs and systems and how they react to toxic agents. Proteomics allow us to understand the targets of toxins in organisms as well as how they react to intoxication. We also want to be on the front line of the discovery on new toxins or to study the occurrence of emergent ones that may be spreading due to global changes. Cyanobacteria and other marine and freshwater organisms are a rich source of secondary metabolites with environmental and human health interest. We wish to find new bioactive compounds that may help to treat diseases or environmental disorders. Allelopatic compounds and antifouling agents are on our list. In terms of human health, we want to find new substances of marine origin with anticancer or antimicrobial properties or compounds that may counter act neurological disorders. As the environment is contaminated by natural or xenobiotic substances we want to find interesting and effective bioremediation approaches to clean the environment. To achieve that, we are using phytoplankton and vascular plants to understand how they can metabolize or uptakes these contaminants and we aim to optimize these processes.

Main Achievements

Evolutionary genomics and proteomic studies

Evolutionary genomics/proteomics studies of cellular protein-coding genes operating in toxins production, detoxification, development, immune system, and genetic disease onset. Inference of the comparative genomic principles from various organisms (from marine microorganisms to mammals) that participate in these processes.

Biochemical and molecular mechanisms of intoxication and detoxication

Mapping of the occurrence of microcystins, cylindrospermopsin and anatoxin-a and their dynamics in organisms (plants, invertebrates, fish). Microcystins promote an in vivo effect in the dynamics of protein phosphatases gene expression, as well as changes in protein expression of Corbicula fluminea and Mytilus galloprovincialis. Production of the neurotoxin ?-N-methylamino-L-alanine (BMAA) by marine and estuarine cyanobacteria.

Bioremediation and early warning systems

Studies on the role of plants and cyanobacteria in conditioning the nearby environment and capability for remediation of metals, nonylphenol, octylphenol, hydrocarbons and natural toxins. Development of early warning systems, using Daphnia magna and Danio rerio and several biomarkers (metabolic rates, phototropism and behavior).

Biotechnology and health implications of marine natural substances

Development of methods for determination of emerging organic contaminants (estrogenic substances, antibiotics) and natural toxins (ANA, CYN, MC and BMAA) in various matrices. Synthesis and characterization of chitosan derivatives, namely, N-(2-Carboxyethyl)chitosans and N-(?-propanoyl-amino acid)-chitosans regarding its environmental and biomedical applications. Survey of bioactive compounds produced by cyanobacteria with interesting pharmacological and environmental health applications. Marine cyanobacteria extracts cause inhibition of herpes simplex virus type 1 Kupka and are neuro-apoptogenic. Discovery of the portoamides as synergistic allelopathic and cytotoxic compounds.

Future Research

Development of new approaches to screen genomes and proteomes of organisms. Evolutionary genomic characterization of genes involved in development and adaptation in vertebrates. Evolutionary genomics of toxic freshwater and marine cyanobacteria and of protoeukaryotes symbioses. Diversity of marine sponge-associated cyanobacteria, production of toxins and nitrogen fixation. Molecular evolution of toxins and toxin producing organisms.

Dynamics of BMAA in several marine organisms and human health risk analysis. New targets of microcystins and unravelling the specific proteins inhibited by cylindrospermopsin. Study of molecular mechanisms involved in the detoxification of cyanotoxins and other substances in metazoans. Study of the toxicity of cyanotoxins using a proteomic approach.

Studies on freshwater phytoplankton interactions with emerging organic contaminants. Studies on suitability of vascular plants (and their microbial community) for application in remediation technologies of metals and organic contaminants (like hydrocarbons and pharmaceuticals). Bioremediation of hydrocarbons and of emerging compounds in coastal areas. Development of new molecular tools for the rapid detection of cyanobacteria and their toxins.

Survey of cyanobacteria extracts for the isolation and characterization of new bioactive compounds with environmental significance (allelopathic, antibiofouling). Impact of cyanobacteria metabolites on human health: antibiotic, antifungic and anticancer properties. Toxicological and ecotoxicological studies of cyanobactins and lantipeptides from cyanobacteria. Tetrodotoxin, conotoxins and other emergent marine toxins occurrence in the Atlantic area.

Most Relevant International Publications

Benziger, A, Philip, S, Raghavan, R, Ali, AP, Sukumaran, M, Tharian, JC, Dahanukar, N, Baby, F, Peter, R, Devi, RK, Radhakrishnan, KV, Haniffa, MA, Britz, R, Antunes, A. 2011. Unraveling a 146 years old taxonomic puzzle: validation of Malabar snakehead, species-status and its relevance for channid systematics and evolution. PLoS One 6(6): e21272.

Leão, PN, Pereira, AR, Liu, WT, Ng, J, Pevzner, PA, Dorrestein, PC, König, GM, Vasconcelos, VM, Gerwick, WH. 2010. Synergistic allelochemicals from a freshwater cyanobacterium. PNAS107(25): 11183-8.

Almeida, CMR, Mucha, AP, Bordalo, AA, Vasconcelos, MTSD. 2008. Influence of a salt marsh plant (Halimione portulacoides) on the concentrations and potential mobility of metals in sediments. Science of the Total Environment 403: 188-195.

Lopes, VR, Schmidtke, M, Fernandes, MH, Martins, R, Vasconcelos, V. 2011. Cytotoxicity in L929 fibroblasts and inhibition of herpes simplex virus type 1 Kupka viruses by estuarine cyanobacteria. Toxicology in Vitro 25: 944-950.

Puerto, M, Campos, A, Prieto, A, Cameán, A, Almeida, AM, Coelho, AV, Vasconcelos, V. 2011. Differential protein expression in two bivalve species; Mytilus galloprovincialis and Corbicula fluminea; exposed to Cylindrospermopsis raciborskii cells. Aquatic Toxicology 101: 109-116.