Accumulation of metals by microorganisms — processes and importance for soil systems

Enhanced Tolerance to Cadmium in Bacterial-Fungal Co-Cultures as a Strategy for Metal Biorecovery from e-Waste

“…Angle medium was chosen for its similarity with the average soil composition, however it seems that the behavior of several organisms changed from the soil to the FH column device (MA culture medium) and further to Petri dish experiments with Angle medium. Therefore, the transition to artificial and less complex culture media as compared to the natural conditions can lead to major changes in the behavior of the isolated microorganisms [66]. Overall, these results show that there are inherent limits to a culture-dependent approach, as it is well known that only a minor fraction of microorganisms is prone to cultivation [21].…”

Zinc bioaccumulation by microbial consortium isolated from nickel smelter sludge disposal site

“…The advantages of the individual components lies in the providing information on metal binding characteristics of individual organisms, but cannot be directly applied to the behaviour of metals in heterogeneous systems. Studies focused on the behaviour of multi-component systems, like a consortium of microorganisms, represent an approach, even if still simplified, closer to the real situations in which bacteria are found in natural systems (Ledin, 2000;Alvarez et al 2017). These advantages mainly consist of synergistic interactions among members of the consortium.…”

Developments in Bioremediation of Soils and Sediments Polluted with Metals and Radionuclides. 3. Influence of Chemical Speciation and Bioavailability on Contaminants Immobilization/Mobilization Bio-processes

“…Microorganisms and plants can have a profound influence on chemical reactions involving contaminants. For example, microorganisms often play a major role in the degradation of organic contaminants and in the oxidation and reduction of heavy metals (Ledin 2000). In the case of plants, the root-soil interfacial region, referred to as the rhizosphere (circled area in soil profile in Figure 1) is an area of particularly intense chemical and biological activity where organic acids, sugars, and other organic compounds are exuded by live plant roots.…”

“…Sorption on mineral surfaces is an important process that can bind and sequester heavy metals and other aqueous contaminant ions (Brown et al 1999;Tessier et al 1996). This process controls the concentrations of metal ions and complexes in the soil/sediment solution and thus exert a major influence on their interactions with bacteria and uptake by plant roots (Jackson et al 1999;Ledin 2000;Bourg & Loch 1995;Huang 2004). Adsorption refers to an ion associated with a surface (organic or mineral) either by (1) chemical interactions through the sharing of electrons (covalent or ionic bonding) or (2) electrostatic attraction involving an ion and surface of opposite charge.…”

“…Although many soil bacteria are tolerant to heavy metals and play important roles in mobilization or immobilization of heavy metals (Ledin 2000), only a few attempts have been made to study the rhizosphere bacteria of metal accumulating and hyperaccumulating plants and their role in the tolerance to and uptake of heavy metals by the plants. However, improvement of the interactions between plants and beneficial rhizosphere microorganisms can enhance biomass production and tolerance of the plants to heavy metals, and are considered is be an important component of phytoremediation technology (Glick 2003).…”