Zhang Ping, Hozalski Raymond M, Leach Lynne H, Camper Anne K, Goslan Emma H, Parsons Simon A, Xie Yuefeng F, LaPara Timothy M
Department of Civil Engineering, University of Minnesota, Minneapolis, 55455-0116, USA.
FEMS Microbiol Lett. 2009 Aug;297(2):203-8. doi: 10.1111/j.1574-6968.2009.01687.x.
Haloacetic acids are a class of disinfection byproducts formed during the chlorination and chloramination of drinking water that have been linked to several human health risks. In this study, we isolated numerous strains of haloacetic acid-degrading Afipia spp. from tap water, the wall of a water distribution pipe, and a granular activated carbon filter treating prechlorinated water. These Afipia spp. harbored two phylogenetically distinct groups of alpha-halocarboxylic acid dehalogenase genes that clustered with genes previously detected only by cultivation-independent methods or were novel and did not conclusively cluster with the previously defined phylogenetic subdivisions of these genes. Four of these Afipia spp. simultaneously harbored both the known classes of alpha-halocarboxylic acid dehalogenase genes (dehI and dehII), which is potentially of importance because these bacteria were also capable of biodegrading the greatest number of different haloacetic acids. Our results suggest that Afipia spp. have a beneficial role in suppressing the concentrations of haloacetic acids in tap water, which contrasts the historical (albeit erroneous) association of Afipia sp. (specifically Afipia felis) as the causative agent of cat scratch disease.
卤乙酸是一类在饮用水氯化和氯胺化过程中形成的消毒副产物，与多种人类健康风险相关。在本研究中，我们从自来水、配水管壁以及处理预氯化水的颗粒活性炭过滤器中分离出了许多能降解卤乙酸的阿菲波尼亚菌属菌株。这些阿菲波尼亚菌属菌株含有两个系统发育上不同的α-卤代羧酸脱卤酶基因群，它们与之前仅通过非培养方法检测到的基因聚集在一起，或者是新的基因，并且没有最终与这些基因先前定义的系统发育亚群聚集在一起。其中四株阿菲波尼亚菌属菌株同时含有已知类别的α-卤代羧酸脱卤酶基因（dehI和dehII），这可能具有重要意义，因为这些细菌还能够对最多数量的不同卤乙酸进行生物降解。我们的结果表明，阿菲波尼亚菌属菌株在抑制自来水中卤乙酸浓度方面具有有益作用，这与阿菲波尼亚菌属（特别是阿菲波尼亚猫菌）作为猫抓病病原体的历史（尽管是错误的）关联形成了对比。
