In conjunction with John Donat and David Burdige at Old Dominion University, we are studying the influence of metal speciation and metal/metal interactions on the particulate cycling and removal of pollutant metals (Zn and Cd) in the Elizabeth River and Hampton Roads Estuaries, home of the Navy’s Atlantic Fleet. We are especially interested in the role of metal uptake by plankton as well as in ...

Calcium sequestration in the hypo-osmotic freshwater environment is imperative in maintaining calcium homeostasis in freshwater aquatic organisms. This uptake process is reported to have the unintended consequence of potentially toxic heavy metal (Cd, Zn) uptake in a variety of aquatic species. However, calcium uptake remains poorly understood in aquatic insects, the dominant invertebrate fauna...

heavy metals are aggressive environmental pollutants. they are easily taken up by plants and they are strong stress factors for plant metabolisms. heavy metals influence includes also disturbances in plant mineral nutrition by competition with other nutrients. the specific objective of this research work was to study whether elevated cr (vi), cd and pb contamination caused an unbalanced nutriti...

Citrate uptake in Bacillus subtilis is stimulated by a wide range of divalent metal ions. The metal ions were separated into two groups based on the expression pattern of the uptake system. The two groups correlated with the metal ion specificity of two homologous B. subtilis secondary citrate transporters, CitM and CitH, upon expression in Escherichia coli. CitM transported citrate in complex ...

The uptake and accumulation of metals occurs in the kidney, which is a key site for interaction between metal nephrotoxicants. The uptake/accumulation and interaction of CdCl2, HgCl2, K2Cr2O7, and NaAsO2 was examined in precision-cut rabbit renal cortical slices. Slices were incubated with 10(-6) to 10(-3) M of a single metal toxicant or combinations of metal toxicants for 12 hr in DME-F12 medi...

Sorption properties of baker's yeast cells, characterised as Saccharomyces cerevisiae were evaluated for trace enrichment of metal ions: Cd(2+), Cr(3+), Cr(6+), Cu(2+), Pb(2+) and Zn(2+) from aqueous environments. Metal concentration was determined by flame atomic absorption spectrometry (FAAS). Parameters affecting metal uptake such as solution pH, incubation time, amount of yeast biomass and ...

Phosphatidylcholine vesicles harboring the lipophilic metal ion carrier A23187 in the bilayer and encapsulating ethylenediamine tetraacetic acid (EDTA) exhibit broadly varied, pH-dependent affinity for Cu2+, Pb2+, Cd2+, and Ca2+ at micromolar levels. Initial rates of uptake by these metal-sorbing vesicles (MSVs) is strongly dependent on the metal ion affinity of A23187 and the dissociation rate...

the aim of this study was to assess the effects of heavy metal tolerant soil microbes inoculation on growth and metal uptake of pearl millet (pennisetum glaucum), couch grass (triticum repens) and alfalfa (medicago sativa) in a soil spiked (and subsequently aged) with increasing concentrations of pb. a soil sample (soil 1) was spiked with increasing (0 to 1500 mg/kg) concentrations of pb and in...