Gram-negative bacteria, such as Escherichia coli, utilize efflux resistance systems in order to expel toxins from their cells. Heavy-metal resistance is mediated by resistance nodulation cell division (RND)-based efflux pumps composed of a tripartite complex that includes an RND-transporter, an outer-membrane factor (OMF), and a membrane fusion protein (MFP) that spans the periplasmic space. MF...

The Czc system of Ralstonia sp. strain CH34 mediates resistance to cobalt, zinc, and cadmium through ion efflux catalyzed by the CzcCB(2)A cation-proton antiporter. The CzcD protein is involved in the regulation of the Czc system. It is a membrane-bound protein with at least four transmembrane alpha-helices and is a member of a subfamily of the cation diffusion facilitator (CDF) protein family,...

The aim of this study was to determine the possibility of using feathers of blue tit nestlings to assess the level of endogenous accumulation of lead. For this purpose we conducted an experiment with lead application to randomly chosen nestlings from eight randomly drawn broods. Five days after the exposure, feathers of lead-treated nestlings had significantly higher lead concentrations than co...

The continuous battle between humans and the multitude of pathogenic microorganisms in the environment has sought relief in the form of antimicrobials. But the counter attack by pathogenic organisms in the form of multidrug resistance, acquired by various mechanisms such as transformation, transposition, conjugation and transduction is a major reason for concern. Bacteriophages have contributed...

algae have been proven efficient biological vectors for heavy metal uptake. in order to further study their biosorption potential, two strains spirogyra sp. and spirulina sp. have been studied under different initial metal concentrations. in recent years, the biosorption processes have been studied extensively using microbial biomass as biosorbent for heavy metal ions removal. in these studies,...

Considering the ever-increasing state of pollution in different aspects of the environment, ornamental plants and herbs such as Lavandula have become the center of attention mostly due to their availability and use in urban green spaces. Phytoremediation is a modern and economical method which can be applied to metropolises for decreasing metal contaminations in soil, water, and atmosphere. Thi...

heavy metal concentration in the soils and sediments has increased worldwide during the last century due to the mining, smelting, and industrial activities. the forumad chromite deposit is located in the sabzevar ophiolitic complex (soc), with a long history of mining activities, yet very little is known about the heavy metal contamination in its surrounding environment. in this research work, ...

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...