A chemiluminescent assay for measuring avermectin binding sites

Avermectins are potent, broad spectrum anthelmintics. We describe the synthesis of a biologically active chemiluminescent compound, 22,23-dihydroavermectin B1a, 4"-[4-[[4-[ethyl(1,2,3,4-tetrahydro-1,4-dioxo-6- phthalazinyl)amino]butyl]amino]-4-oxobutanoate] (ivermectin-luminol). This compound retains its anthelmintic properties and provides an extremely sensitive nonradioactive probe to study avermectin binding sites.     

BIOLUMINESCENCE IN THE MARINE DINOFLAGELLATE PYROCYSTIS LUNULA

Intragenomic nrDNA ITS variability was examined in representative species of the Stephanodiscus niagarae complex. PCR was performed on DNA extracted from monoclonal cultures, and sequence variability determined using standard cloning techniques. Preliminary data from all species reveal intragenomic polymorphism. ITS sequence data is being used to delineate closely related species of algae and polymorphisms are potentially problematic for phylogenetic reconstruction and identity. We are exploring the extent of polymorphism in other freshwater Thalassiorsiraceae, including Stephanodiscus hantzschii fo. tenuis and Cyclostephanos invisitatus.