Sandia National Laboratories, Albuquerque, NM 87185-0754, USA.
J Appl Microbiol. 2009 Jul;107(1):287-99. doi: 10.1111/j.1365-2672.2009.04206.x. Epub 2009 Mar 27.
The hypothesis that surrogate planktonic pathogens (Bacillus cereus and polystyrene microspheres) could be integrated in biofilms and protected from decontamination was tested.
Pseudomonas fluorescens biofilms were grown on polyvinyl chloride coupons in annular reactors under low nutrient conditions. After biofilm growth, B. cereus spores and polystyrene microspheres (an abiotic control) were introduced separately. Shear stress at the biofilm surface was varied between 0.15 and 1.5 N m(-2). The amount of surrogate pathogens introduced ranged from approximately 10(5) CFU ml(-1) to 10(10 )spheres ml(-1). The quantity of surrogate pathogens integrated in the biofilm was proportional to the amount introduced. In 14 of the 16 cases, 0.4-3.0% of the spores or spheres introduced were measured in the biofilms. The other two cases had 10% and 21% of the spores detected. Data suggested that the spores germinated in the system. The amount of surrogate pathogens detected in the biofilms was higher in the mid-shear range. Chlorine treatment reduced the quantity of both surrogate pathogens and biofilm organisms. In one experiment, the biofilms and B. cereus recovered when the chlorine treatment was terminated.
Planktonic surrogate pathogens can be integrated in biofilms and protected from chlorination decontamination.
This knowledge assists in understanding the impact of biofilms on harbouring potential pathogens in drinking-water systems and protecting the pathogens from decontamination.
本研究假设替代浮游病原体（蜡样芽孢杆菌和聚苯乙烯微球）可整合到生物膜中，并免受消毒的影响。
在低营养条件下，使用环形反应器在聚氯乙烯（PVC）薄片上培养荧光假单胞菌生物膜。生物膜生长后，分别引入蜡样芽孢杆菌孢子和聚苯乙烯微球（非生物对照）。生物膜表面的剪切应力在 0.15 至 1.5 N m(-2)之间变化。引入的替代病原体数量约为 10(5) CFU ml(-1)至 10(10)个球体 ml(-1)。整合到生物膜中的替代病原体的数量与引入的数量成正比。在 16 个案例中的 14 个中，检测到引入的孢子或球体中有 0.4-3.0%存在于生物膜中。另外两个案例检测到 10%和 21%的孢子。数据表明，孢子在系统中发芽了。在中剪切范围内，生物膜中检测到的替代病原体数量更高。氯处理减少了替代病原体和生物膜生物的数量。在一项实验中，当氯处理结束时，生物膜和蜡样芽孢杆菌恢复了。
浮游替代病原体可以整合到生物膜中，并免受氯化消毒的影响。
这项知识有助于理解生物膜对饮用水系统中潜在病原体的影响，并保护病原体免受消毒的影响。
