title: Sensitivity to copper in a ciliate as a possible component of biological monitoring in the lagoon of venice
abstract: The impact of copper was studied in cultures of the microbenthic organism Euplotes vannus (Ciliophora, Hypotrichida). This ciliate was isolated from sediment collected from a particular area in the Lagoon of Venice, which may be considered almost unpolluted by heavy metals. The effects of copper exposure in the laboratory on growth, metal accumulation, total acid-soluble thiol levels, and glutathione levels were examined, together with morphological alterations. E. vannus exhibited tolerance toward copper up to a concentration exposure of 0.2 &mgr;g Cu/ml, at which cell growth rate overlapped that of controls. Copper accumulated up to 239 &mgr;g/g dry wt after exposure to 0.4 &mgr;g Cu/ml, and morphological alterations were evident in cells exposed to concentrations from this value upward. Processes of vegetative reorganization involving nuclear apparatus, membranelles, cirri, and cortex could be observed after 4 days of exposure to 0.4 &mgr;g Cu/ml. Laboratory experiments with cultures of ciliates of cosmopolitan distribution such as Euplotes species in controlled conditions indicated the value of these organisms, which constitute a simple model for a monitoring system suitable for prediction in multicellular organisms.
authors.affiliation: Department of Biology, University of Padova, Via G. Colombo 3, 35131 Padova, Italy.
authors.initials: O
authors.lastname: Coppellotti