The mucosal surfaces of fish serve as the first line of defense against the myriad of aquatic pathogens present in the aquatic environment. The immune repertoire functioning at these interfaces is still poorly understood. The skin, in particular, must process signals from several fronts, sensing and integrating environmental, nutritional, social, and health cues. Pathogen invasion can disrupt t...

Bacterial lipases play important roles in bacterial metabolism and environmental response. Our laboratory recently discovered that a novel lipoprotein lysophospholipase, VolA, localizes on the surface of the Gram-negative aquatic pathogen Vibrio cholerae. VolA functions to cleave exogenous lysophosphatidylcholine, freeing the fatty acid moiety for use by V. cholerae. This fatty acid is transpor...

Aeromonas hydrophila, a normal inhabitant of aquatic environments, is an opportunistic pathogen of a variety of aquatic and terrestrial animals, including humans. A. hydrophila PPD134/91 is defined as virulent whereas PPD35/85 is defined as avirulent on the basis of their different LD50 values in fish. Suppression subtractive hybridization (SSH) was used to identify genetic differences between ...

The decline of freshwater fish biodiversity corroborates the trends of unsustainable pesticide usage and increase of disease incidence in the last few decades. Little is known about the role of nonlethal exposure to pesticide, which is not uncommon, and concurrent infection of opportunistic pathogens in species decline. Moreover, preventative measures based on current knowledge of stress biolog...

ToxR, a transmembrane regulatory protein, has been shown to respond to environmental stimuli. To better understand how the aquatic bacterium Vibrio anguillarum, a fish pathogen, responds to environmental signals that may be necessary for survival in the aquatic and fish environment, toxR and toxS from V. anguillarum serotype O1 were cloned. The deduced protein sequences were 59 and 67% identica...

in vitro assessment of the antifungal activities was evaluated in the present study for both aqueous and ethanol extracts prepared from leaves of avicennia marina and rhizophora mucronata . leaves of mangrove species were collected from qeshm and syrik of south-east coast of iran, mangrove forest respectively. antimicrobial tests were carried out through disk diffusion method. minimum fungicida...

Viruses may be major structuring elements of phytoplankton communities and hence important regulators of nutrient and energy fluxes in aquatic environments. In order to ascertain whether viruses are potentially important in dictating phytoplankton community structure, it is essential to determine the extent to which representative phytoplankton taxa are susceptible to viral infection. We used a...

Invasive aquatic plants are an ever-growing nuisance to water resources in Mississippi and the rest of the United States. These plants are generally introduced from other parts of the world, some for beneficial or horticultural uses. Once introduced, they can interfere with navigation, impede water flow, increase flood risk, reduce hydropower generation, and increase evapotranspirational losses...

The antibacterial activities of hexane, ethyl acetate, acetone, ethanolic, methanolic and aqueous extracts of Mangifera indica kernel were studied in vitro against aquatic pathogens viz. Aeromonas hydrophila (six strains), Pseudomonas putida (three strains), P. aeruginosa (three strains), P. fluorescens (two strains), Flavobacterium columnare (three strains), Vibrio parahaemolyticus (two strain...

An important question for mosquito population dynamics, mosquito-borne pathogen transmission and vector control is how mosquito populations are regulated. Here we develop simple models with heterogeneity in egg laying patterns and in the responses of larval populations to crowding in aquatic habitats. We use the models to evaluate how such heterogeneity affects mosquito population regulation an...