Trajanovska S, Britz M L, Bhave M
Department of Biological and Food Sciences, Victoria University of Technology, Melbourne, Australia.
Biodegradation. 1997;8(2):113-24. doi: 10.1023/a:1008212614677.
Resistance to a range of heavy metal ions was determined for lead-resistant and other bacteria which had been isolated from a battery-manufacturing site contaminated with high concentration of lead. Several Gram-positive (belonging to the genera Arthrobacter and Corynebacterium) and Gram-negative (Alcaligenes species) isolates were resistant to lead, mercury, cadmium, cobalt, zinc and copper, although the levels of resistance to the different metal ions were specific for each isolate. Polymerase chain reaction, DNA-DNA hybridization and DNA sequencing were used to explore the nature of genetic systems responsible for the metal resistance in eight of the isolates. Specific DNA sequences could be amplified from the genomic DNA of all the isolates using primers for sections of the mer (mercury resistance determinant on the transposon Tn501) and pco (copper resistance determinant on the plasmid pRJ1004) genetic systems. Positive hybridizations with mer and pco probes indicated that the amplified segments were highly homologous to these genes. Some of the PCR products were cloned and partially sequenced, and the regions sequenced were highly homologous to the appropriate regions of the mer and pco determinants. These results demonstrate the wide distribution of mercury and copper resistance genes in both Gram-positive and Gram-negative isolates obtained from this lead-contaminated soil. In contrast, the czc (cobalt, zinc and cadmium resistance) and chr (chromate resistance) genes could not be amplified from DNAs of some isolates, indicating the limited contribution, if any, of these genetic systems to the metal ion resistance of these isolates.
对从一个被高浓度铅污染的电池制造场地分离出的耐铅细菌和其他细菌，测定了它们对一系列重金属离子的抗性。几种革兰氏阳性菌（属于节杆菌属和棒杆菌属）和革兰氏阴性菌（产碱菌属）分离株对铅、汞、镉、钴、锌和铜具有抗性，尽管每种分离株对不同金属离子的抗性水平有所不同。利用聚合酶链反应、DNA - DNA杂交和DNA测序技术，对其中8株分离株中负责金属抗性的遗传系统的性质进行了探究。使用针对mer（转座子Tn501上的汞抗性决定簇）和pco（质粒pRJ1004上的铜抗性决定簇）遗传系统部分区域的引物，可从所有分离株的基因组DNA中扩增出特定的DNA序列。与mer和pco探针的阳性杂交表明，扩增片段与这些基因高度同源。部分PCR产物被克隆并进行了部分测序，测序区域与mer和pco决定簇的相应区域高度同源。这些结果表明，从该铅污染土壤中获得的革兰氏阳性和革兰氏阴性分离株中，汞和铜抗性基因广泛分布。相比之下，一些分离株的DNA中无法扩增出czc（钴、锌和镉抗性）和chr（铬酸盐抗性）基因，这表明这些遗传系统对这些分离株的金属离子抗性贡献有限（如果有贡献的话）。
