Copper plays a dual role in aerobic organisms, as both an essential and a potentially toxic element. To ensure copper availability while avoiding its toxic effects, organisms have developed complex homeostatic networks to control copper uptake, distribution, and utilization. In eukaryotes, including yeasts and mammals, high affinity copper uptake is mediated by the Ctr family of copper transpor...

Silene vulgaris (Moench) Garcke has evolved populations with extremely high levels of copper tolerance. To evaluate the role of metallothioneins (MTs) in copper tolerance in S. vulgaris, we screened a cDNA library derived from a highly copper-tolerant population using Arabidopsis-based MT probes and identified an MT2b-like gene. When expressed in yeast, this gene, SvMT2b, restored cadmium and c...

We studied effects of free copper ion activity and total copper concentration on copper uptake by lettuce from nutrient solution and a model was developed. In ethylenediaminetetraacetic acid and dissolved organic matter treatments, when pH and free copper ion activity were the same, root copper concentration did not change with the total copper concentration. However, at fixed pH and total copp...

A randomized complete block (RCBD) study was designed to investigate the effects of cadmium (Cd) and copper (Cu) on the growth, bioaccumulation of the two heavy metals, metabolite content and antibacterial activities in Gyanura procumbens (Lour.) Merr. Nine treatments including (1) control (no Cd and Cu); (2) Cd 2 = cadmium 2 mg/L; (3) Cd 4 = cadmium 4 mg/L; (4) Cu 70 = copper 70 mg/L; (5) Cu 1...

Salicylic acid (SA) plays a key role in plant disease resistance and hyper-sensitive cell death but is also implicated in hardening responses to abiotic stress. The aim of this study is to examine the effects of salicylic acid on the growth, eco-physiological and biochemical characteristics in Zinnia elegans plant exposed to copper stress. Effects of copper (Cu) on biomass, root length and shoo...

Major copper proteins in the cytoplasm of plant cells are plastocyanin, copper/zinc superoxide dismutase, and cytochrome c oxidase. Under copper limited conditions, expression of copper/zinc superoxide dismutase is down-regulated and the protein is replaced by iron superoxide dismutase in chloroplasts. We present evidence that a micro-RNA, miR398, mediates this regulation in Arabidopsis thalian...

Copper-resistant strains of Pseudomonas syringae carrying the cop operon produce periplasmic copper-binding proteins, and this sequestration outside the cytoplasm has been proposed as a resistance mechanism. In this study, strain PS61 of P. syringae carrying the cloned cop operon accumulated more total cellular copper than without the operon. Several other copper-resistant pseudomonads with hom...

Background: Soil and plant contamination in copper exposure causes chronic copper poisoning (CCP) in animals following the consumption of plants in these soils. Objectives: The present study was carried out on 10 clinically affected copper poisoned cases (in each season) from autumn 2015 to the end of summer 2016, in four seasons in Kerman province to evaluate the seasonal effects of CCP in she...