These soils were sampled from a pasture soil located in North Chagres (longitude 70º57’29.95” W and latitude 32º46’37.42” S), an artichoke plantation https://www.selleckchem.com/products/Romidepsin-FK228.html soil from South Chagres (longitude 70º57’57.169” W and latitude 32º48’30.254” S) located 3.5 km distant from North Chagres site and an olive plantation soil from Ñilhue (longitude 70º54’40.628” W and latitude 32º41’44.577” S) located 10.8 and 13.5 km distant from
North and South Chagres sites, respectively. Soils were sampled on 6 August 2009. These soils had a Cu content that ranged from 379 to 784 mg kg-1 dry weight soil (d.w.s). The concentrations exceed the standard acceptable level of 40 mg kg-1 for Thiazovivin soil by the Québec regulatory authorities (Ministère de l’ Environnement du Québec, 1999). A pasture soil from a non-polluted site was sampled from the mTOR inhibitor Casablanca valley, central Chile on 5 August 2010. The non-polluted site was located in La Vinilla (longitude 71º24’36” W and latitude 32º19’30.254” S) located 62–68 km distant from the three polluted sites. Soil samples were air-dried and sieved to 2 mm and homogenized. The soil samples were stored in polyethylene bags and preserved in a dark room at 4°C until analyses. Figure 1 Location of sampling sites of agricultural soils in Valparaíso
region, central Chile. North Chagres, South Chagres and Ñilhue are Cu-polluted sites. La Vinilla is a non-polluted site. Soil chemical analyses Soil pH was measured
using a 1:2 (w/v) a soil/deionized water mixture. The organic matter content was determined by the dichromate oxidation . For Tyrosine-protein kinase BLK heavy metal analyses (Cu, Zn, Pb, Cr and Ni), soils were digested with a 10:4:1 HNO3/HClO4/H2SO4 mixture. Exchangeable Cu from soils (1 g d.w.s) was extracted with 10 ml of MgCl2 solution (1 M, pH 7) at room temperature with continuous agitation for 1 h. Total heavy metal content and the exchangeable Cu were quantified by atomic absorption spectrometry (AAS) using Spectraa-800 spectrophotometer Varian (Santa Clara, CA, USA). DNA extraction from soil Metagenomic DNA was extracted from 0.5 g of soil in triplicate using the FastDNA Spin Kit for soil (MP Biomedicals, Solon, Ohio, USA). Cells were disrupted using the FastPrep-24 instrument (MP Biomedicals, Solon, Ohio, USA) following the manufacturer’s instructions. Subsequently, the DNA extract was purified by GeneClean Spin Kit (MP Biomedicals, Solon, Ohio, USA). DNA was quantified using Qubit fluorometer (Invitrogen, Carlsbad, CA, USA). Bacterial community analyses Bacterial communities from soils were evaluated using DGGE.