Transverse bacterial migration induced by chemotaxis in a packed column with structured physical heterogeneity.
Transverse bacterial migration induced by chemotaxis in a packed column with structured physical heterogeneity.
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DOI：
10.1021/es901001t
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发表时间：
2009-08-01
影响因子：
11.4
通讯作者：
Ford, Roseanne M.
中科院分区：
文献类型：
--
作者：
Wang, Meng;Ford, Roseanne M.
在地下水流条件下，研究了趋化性在天然多孔介质中引导细菌向污染物迁移中的意义。实验室规模的柱，粗粒度的砂芯周围的细粒环，被用来模拟天然含水层与不同的水力传导率的地层。将化学引诱物源沿着柱的中心轴放置，以模拟捕获在非均质地下的污染物。趋化性细菌菌株，大肠杆菌HCB 1和恶臭假单胞菌F1，引入到列的脉冲注射，发现改变其运输行为的影响下，从中央源发出的引诱剂化学品。大肠coliHCB 1，在平均流速为5.1m/d时，由于α-甲基天冬氨酸的趋化作用，从粗砂层中离开的总种群比不加引诱剂的对照多18%。在相同的流速下，恶臭假单胞菌F1在模拟污染物乙酸盐的作用下，其迁移路径没有明显变化，但当流速降低到1.9 m/d时，约有6~10%的种群从细砂层向引诱剂迁移进入粗砂层。通过数学模型进一步量化了微生物的运输特性，以考察不同水动力条件下细菌运动性和趋化性的重要性，这为菌株选择和生物修复方案的实际操作提供了重要考虑因素。
The significance of chemotaxis in directing bacterial migration towards contaminants in natural porous media was investigated under groundwater flow conditions. A laboratory-scale column, with a coarse-grained sand core surrounded by a fine-grained annulus, was used to simulate natural aquifers with strata of different hydraulic conductivities. A chemoattractant source was placed along the central axis of the column to model contaminants trapped in the heterogeneous subsurface. Chemotactic bacterial strains, Escherichia coli HCB1 and Pseudomonas putida F1, introduced into the column by a pulse injection, were found to alter their transport behaviors under the influence of the attractant chemical emanating from the central source. For E. coli HCB1, approximately 18% more of the total population relative to the control without attractant exited the column from the coarse sand layer due to the chemotactic effects of α-methylaspartate under an average fluid velocity of 5.1 m/d. Although P. putida F1 demonstrated no observable changes in migration pathways with the model contaminant acetate under the same flow rate, when the flow rate was reduced to 1.9 m/d, approximately 6~10% of the population relative to the control migrated from the fine sand layer towards attractant into the coarse sand layer. Microbial transport properties were further quantified by a mathematical model to examine the significance of bacterial motility and chemotaxis under different hydrodynamic conditions, which suggested important considerations for strain selection and practical operation of bioremediation schemes.
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影响因子：
3.8
作者：
FORD, RM;PHILLIPS, BR;LAUFFENBURGER, DA
通讯作者：
LAUFFENBURGER, DA
影响因子：
4.4
作者：
Grimm, AC;Harwood, CS
通讯作者：
Harwood, CS
影响因子：
3.6
作者：
Gierczak, RFD;Devlin, JF;Rudolph, DL
通讯作者：
Rudolph, DL
影响因子：
2.7
作者：
Marcos;Stocker, Roman
通讯作者：
Stocker, Roman
影响因子：
4.7
作者：
Ford, Roseanne M.;Harvey, Ronald W.
通讯作者：
Harvey, Ronald W.