Roane T M, Kellogg S T
Department of Microbiology, Molecular Biology and Biochemistry, University of Idaho, Moscow 83844-3052, USA.
Can J Microbiol. 1996 Jun;42(6):593-603. doi: 10.1139/m96-080.
Heavy metal pollution is a principle source of environmental contamination. We analyzed heavy metal impacted soil microbial communities and found that, in general, although lead adversely affected biomass, metabolic activity, and diversity, autochthonous lead- and cadmium-resistant isolates were found. In several metal-stressed soils, the microbial community consisted of two populations, either resistant or sensitive to lead. Additionally, a lead-resistant isolate was isolated from a control soil with no known previous exposure to lead, suggesting widespread lead resistance. Lead-resistant genera isolated included Pseudomonas, Bacillus, Corynebacterium, and Enterobacter species. Plasmids, ranging from 5 to 260 kb, were not detected through standard purifications from lead-resistant isolates. Positive correlations existed between antibiotic resistance and isolation habitat for lead-resistant strains, microbial metabolic activity and soil type, soluble lead concentration and microbial diversity, and arsenic concentration and total or viable cell concentrations.
重金属污染是环境污染的主要来源。我们分析了受重金属影响的土壤微生物群落，发现总体而言，尽管铅对生物量、代谢活性和多样性有不利影响，但仍发现了本地的耐铅和镉分离株。在几种受金属胁迫的土壤中，微生物群落由对铅有抗性或敏感的两个种群组成。此外，从先前未知有铅暴露史的对照土壤中分离出了一株耐铅分离株，这表明耐铅现象广泛存在。分离出的耐铅属包括假单胞菌属、芽孢杆菌属、棒状杆菌属和肠杆菌属。通过从耐铅分离株中进行标准纯化，未检测到大小在5至260 kb之间的质粒。耐铅菌株的抗生素抗性与分离生境、微生物代谢活性与土壤类型、可溶性铅浓度与微生物多样性以及砷浓度与总细胞浓度或活细胞浓度之间存在正相关。
