TY - JOUR
T1 - Toxic effects of zinc on anaerobic microbiota from Zimapán Reservoir (Mexico)
AU - Vega-López, Armando
AU - Amora-Lazcano, Enriqueta
AU - López-López, Eugenia
AU - Terrón, Oscar
AU - Proal-Nájera, José B.
PY - 2007/4
Y1 - 2007/4
N2 - The toxic effects of heavy metals have been extensively documented in different organisms. Nevertheless, a lack of information exists with regard to this topic in the case of autochthonous microorganism communities. The aim of this study was to evaluate the toxic effects of zinc on the anaerobic microorganisms present in the sediment and anoxic water of Zimapán Reservoir (Mexico), with particular focus on dissimilatory sulphate reducing bacteria. In the laboratory, a system of enrichment microcosms was set up with sediment and water from the reservoir. ATP, protein, carbohydrates and lactate and alcohol dehydrogenase activity were determined. The physicochemical parameters of the reservoir were evaluated over the course of one year. Sulphate reduction occurred in the reservoir throughout the year, but was most pronounced at the end of the wet season and during winter. In the field, increases in the rate of sulphate reduction coincided with the lowest levels of total phosphorus and hydrosoluble organic carbon. Zinc enrichment was observed to modify protein and carbohydrate content as well as to affect lactate and alcohol dehydrogenase activity. All responses followed a zinc concentration-response relationship and were dependent on reservoir physicochemical parameters. ATP content was used as a biomarker to evaluate the sublethal toxic effects of zinc. The acceptable threshold concentration of zinc in the aquatic and sediment enrichment microcosms was determined to be 0.06 mg Zn/L and 711.1 mg Zn/kg, respectively.
AB - The toxic effects of heavy metals have been extensively documented in different organisms. Nevertheless, a lack of information exists with regard to this topic in the case of autochthonous microorganism communities. The aim of this study was to evaluate the toxic effects of zinc on the anaerobic microorganisms present in the sediment and anoxic water of Zimapán Reservoir (Mexico), with particular focus on dissimilatory sulphate reducing bacteria. In the laboratory, a system of enrichment microcosms was set up with sediment and water from the reservoir. ATP, protein, carbohydrates and lactate and alcohol dehydrogenase activity were determined. The physicochemical parameters of the reservoir were evaluated over the course of one year. Sulphate reduction occurred in the reservoir throughout the year, but was most pronounced at the end of the wet season and during winter. In the field, increases in the rate of sulphate reduction coincided with the lowest levels of total phosphorus and hydrosoluble organic carbon. Zinc enrichment was observed to modify protein and carbohydrate content as well as to affect lactate and alcohol dehydrogenase activity. All responses followed a zinc concentration-response relationship and were dependent on reservoir physicochemical parameters. ATP content was used as a biomarker to evaluate the sublethal toxic effects of zinc. The acceptable threshold concentration of zinc in the aquatic and sediment enrichment microcosms was determined to be 0.06 mg Zn/L and 711.1 mg Zn/kg, respectively.
KW - ATP
KW - Alcohol dehydrogenase
KW - Dissimilatory sulphate reducing bacteria
KW - Lactate dehydrogenase
KW - Zinc
UR - http://www.scopus.com/inward/record.url?scp=34447106699&partnerID=8YFLogxK
U2 - 10.1016/j.anaerobe.2007.01.001
DO - 10.1016/j.anaerobe.2007.01.001
M3 - Artículo
C2 - 17360200
SN - 1075-9964
VL - 13
SP - 65
EP - 73
JO - Anaerobe
JF - Anaerobe
IS - 2
ER -