RAPID ASSAY FOR SCREENING AND CHARACTERIZING MICROORGANISMS FOR THE ABILITY TO DEGRADE POLYCHLORINATED-BIPHENYLS
RAPID ASSAY FOR SCREENING AND CHARACTERIZING MICROORGANISMS FOR THE ABILITY TO DEGRADE POLYCHLORINATED-BIPHENYLS
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DOI：
10.1128/aem.51.4.761-768.1986
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发表时间：
1986-04-01
影响因子：
4.4
通讯作者：
JOHNSON, C
中科院分区：
文献类型：
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作者：
BEDARD, DL;UNTERMAN, R;JOHNSON, C
我们设计了一种快速检测方法，（一）评估多氯联苯（PCB）的降解能力和同源物的好氧微生物的特异性，（二）确定菌株能够降解高氯联苯，和（三）区分那些降解多氯联苯的替代途径。以前试图通过测量Aroclors（多氯联苯商用混合物）的消失情况来测定多氯联苯的降解能力，但由于挥发、吸附或吸收损失，经常产生假阳性结果。此外，由于气相色谱分离不完全和多氯联苯峰的鉴别不确定，这些测定通常使活性的化学性质模糊不清。我们避免了这些问题，通过使用确定的混合物的多氯联苯同系物，并通过采用孵化和提取方法，防止物理损失的多氯联苯。我们的检测混合物包括PCB同系物，范围从二氯联苯到六氯联苯，代表各种结构类别，例如，在单环上氯化的同系物（2，3-二氯联苯），在2，3个位点封闭的同系物（2，5，2“5”-四氯联苯），在3，4个位点封闭的同系物（4，4“-二氯联苯），以及缺乏相邻的未氯化位点的同系物（2，4，5，2”，4“，5”-六氯联苯）。微生物的多氯联苯降解能力评估填充柱气相色谱分析这些确定的同系物混合物24小时孵育后，与静息细胞。当使用25种环境分离株进行测试时，该测定（i）揭示了广泛的PCB降解能力，（ii）强调了同源物特异性和单个同源物降解程度的差异，（iii）预测了对商业PCB的降解能力，以及（iv）鉴定了具有上级PCB降解能力的菌株。
We designed a rapid assay that (i) assesses the polychlorinated biphenyl (PCB)-degradative competence and congener specificity of aerobic microorganisms, (ii) identifies strains capable of degrading highly chlorinated biphenyls, and (iii) distinguishes among those that degrade PCBs by alternative pathways. Prior attempts to assay PCB-degradative competence by measuring disappearance of Aroclors (commercial PCB mixtures) have frequently produced false-positive findings because of volatilization, adsorption or absorption losses. Furthermore, these assays have generally left the chemical nature of the competence obscure because of incomplete gas chromatographic resolution and uncertain identification of Aroclor peaks. We avoided these problems by using defined mixtures of PCB congeners and by adopting incubation and extraction methods that prevent physical loss of PCBs. Our assay mixtures include PCB congeners ranging from dichloro- to hexachlorobiphenyls and representing various structural classes, e.g., congeners chlorinated on a single ring (2,3-dichlorobiphenyl), blocked at 2,3 sites (2,5,2''5''-tetrachlorobiphenyl), blocked at 3,4 sites (4,4''-dichlorobiphenyl), and lacking adjacent unchlorinated sites (2,4,5,2'',4'',5''-hexachlorobiphenyl). The PCB-degradative ability of microorganisms is assessed by packed-column gas chromatographic analysis of these defined congener mixtures following 24-h incubation with resting cells. When tested with 25 environmental isolates, this assay (i) revealed a broad range of PCB-degradative competence, (ii) highlighted differences in congener specificity and in the extent of degradation of individual congeners, (iii) predicted degradative competence on commercial PCBs, and (iv) identified strains with superior PCB-degradtive ability.