Laboratory of Genetics and Biotechnology, Center of Studies for Nuclear Energy, S.C.K.-C.E.N., B-2400 Mol, Belgium.
Appl Environ Microbiol. 1990 May;56(5):1485-91. doi: 10.1128/aem.56.5.1485-1491.1990.
Alcaligenes eutrophus CH34 DNA fragments encoding resistance to Cd, Co, Zn (czc), or Hg (merA) were cloned and used as probes in colony hybridization procedures with bacteria isolated from polluted environments such as a zinc factory area (desertified because of the toxic effects of zinc contamination) and from sediments from factories of nonferrous metallurgy in Belgium and mine areas in Zaire. From the different soil samples, strains could be isolated and hybridized with the czc probe (resistance to Cd, Co, and Zn from plasmid pMOL30). Percentages of CFU isolated on nonselective plates which hybridized with the czc and the mercury resistance probes were, respectively, 25 and 0% for the zinc desert, 15 to 20 and 10 to 20% for the two Belgian factories, and 40 and 40% for the Likasi mine area. Most of these strains also carried two large plasmids of about the same size as those of A. eutrophus CH34 and shared many phenotypic traits with this strain. These findings indicated a certain correlation between the heavy-metal content in contaminated soils and the presence of heavy-metal-resistant megaplasmid-bearing A. eutrophus strains.
产碱杆菌 CH34 的 DNA 片段编码对 Cd、Co、Zn（czc）或 Hg（merA）的抗性，这些片段被克隆并用作探针，用于与从污染环境中分离的细菌进行菌落杂交程序，这些污染环境包括锌厂地区（由于锌污染的毒性作用而沙漠化）和比利时的有色冶金厂以及扎伊尔的矿区的沉积物。从不同的土壤样本中，可以分离出与 czc 探针（来自质粒 pMOL30 的对 Cd、Co 和 Zn 的抗性）杂交的菌株。在非选择性平板上分离的 CFU 百分比，与 czc 和汞抗性探针杂交的百分比分别为锌沙漠地区的 25%和 0%，两个比利时工厂的 15%至 20%和 10%至 20%，以及利卡西矿区的 40%和 40%。这些菌株中的大多数还携带两个与产碱杆菌 CH34 大小大致相同的大型质粒，并与该菌株具有许多表型特征。这些发现表明，污染土壤中的重金属含量与携带重金属抗性大质粒的产碱杆菌菌株的存在之间存在一定的相关性。
