Soares E V, Duarte A P R S, Boaventura R A, Soares H M V M
CIEA-Departamento de Engenharia Química, Instituto Superior de Engenharia do Instituto Politécnico do Porto, Rua Dr António Bernardino de Almeida, 431, 4200-072 Porto, Portugal.
Appl Microbiol Biotechnol. 2002 May;58(6):836-41. doi: 10.1007/s00253-002-0947-2. Epub 2002 Mar 2.
Saccharomyces cerevisiae NCYC 1190 cells accumulated (after 1 h) lead and cadmium at similar levels, and to a lesser degree also copper. During heavy metal accumulation, there was a considerable loss of viability of copper-treated cells (about 99% in the first 20 min of contact with the metal), and a less pronounced lethal effect on cadmium- and lead-treated cells (about 66% and 46% after 1 h of contact with cadmium or lead, respectively) was detected. During copper accumulation, a leakage of UV-absorbing compounds and inorganic phosphate was observed; this did not occur with lead, whereas with cadmium a small amount of leakage of inorganic phosphate was detected. The filtrates of copper-treated cells contained copper-binding molecules. The copper-binding capacity of the filtrates increased with time according to the release of inorganic phosphate and UV-absorbing compounds. These compounds can bind an appreciable quantity of metal ions, making them unavailable for cell uptake and thus reducing the efficiency of heavy metals removal by yeast cells.
酿酒酵母NCYC 1190细胞（1小时后）积累的铅和镉水平相似，积累的铜较少。在重金属积累过程中，铜处理的细胞活力有相当大的损失（在与金属接触的前20分钟约为99%），对镉和铅处理的细胞的致死效应不那么明显（与镉或铅接触1小时后分别约为66%和46%）。在铜积累过程中，观察到有紫外线吸收化合物和无机磷酸盐的泄漏；铅处理时未出现这种情况，而镉处理时检测到少量无机磷酸盐泄漏。铜处理细胞的滤液中含有铜结合分子。滤液的铜结合能力随无机磷酸盐和紫外线吸收化合物的释放而随时间增加。这些化合物可以结合相当数量的金属离子，使其无法被细胞摄取，从而降低酵母细胞去除重金属的效率。
