Chemical defense in developmental stages and adult of the sea star () .

To date, evidence regarding the performance of secondary metabolites from larval stages of sea stars as an anti-predation defense relates only to a few species/specimens from a few geographic ranges. Unfortunately, this hinders a comprehensive global understanding of this inter-specific predator-prey interaction. Here, we present laboratory experimental evidence of chemical defense action in the early developmental stages and adults of the sea star () from Brazil against sympatric and allopatric invertebrate consumers.

Molecular analysis of a fungal disease in the habitat-forming brown macroalga Phyllospora comosa (Fucales) along a latitudinal gradient.

Infectious diseases affecting habitat-forming species can have significant impacts on population dynamics and alter the structure and functioning of marine ecosystems. Recently, a fungal infection was described as the causative agent of necrotic lesions on the stipe of the forest-forming macroalga Phyllospora comosa, a disease named "stipe rot" (SR). Here, we developed a quantitative PCR (qPCR) method for rapid detection and quantification of this pathogen, which was applied to evaluate the level of SR infection in eight P.

Molecular Mechanisms for Microbe Recognition and Defense by the Red Seaweed .

The ability to recognize and respond to the presence of microbes is an essential strategy for seaweeds to survive in the marine environment, but understanding of molecular seaweed-microbe interactions is limited. clones were inoculated with the marine bacterium . The seaweed RNA was sequenced, providing an unprecedentedly high coverage of the transcriptome of , and the gene expression levels were compared between control and inoculated samples after 24, 48, and 72 h.

Chemical Defense as a Condition-Dependent Trait in Harvestmen.

The expression of costly traits often depends on the amount of food available to the individuals. Chemical defenses are costly, thus their production should be condition-dependent. Here, we tested the hypothesis that an increase in food availability and an acetate-supplemented diet will increase the production of chemical defenses by the harvestman Magnispina neptunus, which releases alkylated benzoquinones biosynthesized using acetate as a precursor.

Additional evidence of the trypanocidal action of (-)-elatol on amastigote forms through the involvement of reactive oxygen species.

Chagas' disease, a vector-transmitted infectious disease, is caused by the protozoa parasite Trypanosoma cruzi. Drugs that are currently available for the treatment of this disease are unsatisfactory, making the search for new chemotherapeutic agents a priority. We recently described the trypanocidal action of (-)-elatol, extracted from the macroalga Laurencia dendroidea.

Trypanocidal action of (-)-elatol involves an oxidative stress triggered by mitochondria dysfunction.

Natural compounds have shown good potential for the discovery of new chemotherapeutics for the treatment of Chagas' disease. Recently, our group reported the effective trypanocidal activity of (-)-elatol, extracted from the red macroalgae Laurencia dendroidea present in the Brazilian coast against Trypanosoma cruzi. However, the mechanism of action of this compound has remained unclear.

Effect of elatol, isolated from red seaweed Laurencia dendroidea, on Leishmania amazonensis.

In the present study, we investigated the antileishmanial activity of sesquiterpene elatol, the major constituent of the Brazilian red seaweed Laurencia dendroidea (Hudson) J.V. Lamouroux, against L.

Induction of halogenated vesicle transport in cells of the red seaweed Laurencia obtusa.

In clones of the red alga Laurencia obtusa, the frequency of vesicle transport from corps en cerise (CC) to the cell wall region was evaluated in response to differences in temperature, irradiance, desiccation, bacterial fouling, and bromine (Br) availability. In addition, the morphology of the corps en cerise was analyzed. Traffic of vesicles was induced by exposing L.

TRANSPORT AND DEFENSIVE ROLE OF ELATOL AT THE SURFACE OF THE RED SEAWEED LAURENCIA OBTUSA (CERAMIALES, RHODOPHYTA)(1).

Natural within-thallus concentrations of elatol produced by Laurencia obtusa (Huds.) J. V.

Quantitative GC-ECD analysis of halogenated metabolites: determination of surface and within-thallus elatol of Laurencia obtusa.

Information on natural concentrations or variability of secondary metabolites in marine organisms may be important both to ecological/evolutionary and applied approaches. A gas chromatographic procedure with an electron capture detector (GC-ECD) was developed to quantify the sesquiterpenoid elatol at the surface and within-thalli of 70 specimens of the red seaweed Laurencia obtusa. The concentration of elatol was highest within-thalli [9.