Amoroso M J, Schubert D, Mitscherlich P, Schumann P, Kothe E
Friedrich-Schiller-Universität, Biologisch-Pharmazeutische Fakultät, Institut für Mikrobiologie, Mikrobielle Phytopathologie, Winzerlaer Str. 10, D-07745 Jena, Germany.
J Basic Microbiol. 2000;40(5-6):295-301. doi: 10.1002/1521-4028(200012)40:5/6<295::aid-jobm295>3.0.co;2-z.
We have isolated 25 new strains of streptomycetes from soil samples of a polluted site at the former uranium mine, Wismut, in eastern Thuringia, Germany. The strains grew on medium containing 1 mM NiCl2 and thus were resistant to the heavy metal ion. Seven of the strains were further characterized. All of these strains were resistant to heavy metals in various degrees with up to 10 mM resistance against NiCl2 supplied with the liquid minimal growth medium. The high level of resistance prompted us to look for high affinity nickel transporter genes thought to provide a means to eliminate the excess nickel ions form the cells. Degenerate oligonucleotide primers derived from sequences of P-type ATPase transporter genes of Gram negative bacteria identified a fragment which shows deduced amino acid sequence similarities to known high affinity nickel transporters. Investigation of two genes obtained from the isolates Streptomyces spec. E8 and F4 showed high sequence divergence. This was unexpected since a transmissible plasmid had been thought to convey heavy metal resistance.
我们从德国图林根州东部原铀矿“维什穆特”污染场地的土壤样本中分离出了25株新的链霉菌菌株。这些菌株能在含有1 mM氯化镍的培养基上生长，因此对重金属离子具有抗性。对其中7株菌株进行了进一步的特性分析。所有这些菌株都对重金属具有不同程度的抗性，在液体基本生长培养基中对氯化镍的抗性高达10 mM。这种高水平的抗性促使我们寻找高亲和力镍转运蛋白基因，认为其可为细胞消除过量镍离子提供一种途径。源自革兰氏阴性菌P型ATP酶转运蛋白基因序列的简并寡核苷酸引物鉴定出了一个片段，该片段显示出与已知高亲和力镍转运蛋白的推导氨基酸序列相似性。对从链霉菌属菌株E8和F4分离得到的两个基因的研究表明，它们的序列差异很大。这出乎意料，因为一直认为可传递质粒会传递重金属抗性。
