Camper A K, McFeters G A, Characklis W G, Jones W L
Center for Interfacial Microbial Process Engineering, Montana State University, Bozeman 59717.
Appl Environ Microbiol. 1991 Aug;57(8):2233-9. doi: 10.1128/aem.57.8.2233-2239.1991.
The growth of environmental and clinical coliform bacteria under conditions typical of drinking water distribution systems was examined. Four coliforms (Klebsiella pneumoniae, Escherichia coli, Enterobacter aerogenes, and Enterobacter cloacae) were isolated from an operating drinking water system for study; an enterotoxigenic E. coli strain and clinical isolates of K. pneumoniae and E. coli were also used. All but one of the coliforms tested were capable of growth in unsupplemented mineral salts medium; the environmental isolates had greater specific growth rates than did the clinical isolates. This trend was maintained when the organisms were grown with low levels (less than 1 mg liter-1) of yeast extract. The environmental K. pneumoniae isolate had a greater yield, higher specific growth rates, and a lower Ks value than the other organisms. The environmental E. coli and the enterotoxigenic E. coli strains had comparable yield, growth rate, and Ks values to those of the environmental K. pneumoniae strain, and all three showed significantly more successful growth than the clinical isolates. The environmental coliforms also grew well at low temperatures on low concentrations of yeast extract. Unsupplemented distribution water from the collaborating utility supported the growth of the environmental isolates. Growth of the K. pneumoniae water isolate was stimulated by the addition of autoclaved biofilm but not by tubercle material. These findings indicate that growth of environmental coliforms is possible under the conditions found in operating municipal drinking water systems and that these bacteria could be used in tests to determine assimilable organic carbon in potable water.
研究了环境和临床大肠菌群在饮用水分配系统典型条件下的生长情况。从一个运行中的饮用水系统中分离出四种大肠菌群（肺炎克雷伯菌、大肠杆菌、产气肠杆菌和阴沟肠杆菌）用于研究；还使用了一株产肠毒素大肠杆菌菌株以及肺炎克雷伯菌和大肠杆菌的临床分离株。除一种受试大肠菌群外，其他所有菌群都能在未添加营养成分的无机盐培养基中生长；环境分离株的比生长速率高于临床分离株。当这些微生物在低水平（低于1毫克/升）酵母提取物存在的情况下生长时，这一趋势仍然存在。环境肺炎克雷伯菌分离株比其他微生物具有更高的产量、更高的比生长速率和更低的Ks值。环境大肠杆菌和产肠毒素大肠杆菌菌株在产量、生长速率和Ks值方面与环境肺炎克雷伯菌菌株相当，并且这三种菌株的生长情况均明显优于临床分离株。环境大肠菌群在低温和低浓度酵母提取物条件下也生长良好。合作公用事业公司未添加营养成分的配水支持环境分离株的生长。添加经高压灭菌的生物膜可刺激肺炎克雷伯菌水分离株的生长，但结核物质则无此作用。这些发现表明，在运行中的城市饮用水系统所存在的条件下，环境大肠菌群有可能生长，并且这些细菌可用于饮用水中可同化有机碳测定的试验。
