Abstract
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.
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- Davies D. G., McFeters G. A. Growth and comparative physiology of Klebsiella oxytoca attached to granular activated carbon particles and in liquid media. Microb Ecol. 1988;15(2):165–175. doi: 10.1007/BF02011710. [DOI] [PubMed] [Google Scholar]
- Edberg S. C., Piscitelli V., Cartter M. Phenotypic characteristics of coliform and noncoliform bacteria from a public water supply compared with regional and national clinical species. Appl Environ Microbiol. 1986 Sep;52(3):474–478. doi: 10.1128/aem.52.3.474-478.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LeChevallier M. W., Babcock T. M., Lee R. G. Examination and characterization of distribution system biofilms. Appl Environ Microbiol. 1987 Dec;53(12):2714–2724. doi: 10.1128/aem.53.12.2714-2724.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zobell C. E., Grant C. W. Bacterial Utilization of Low Concentrations of Organic Matter. J Bacteriol. 1943 Jun;45(6):555–564. doi: 10.1128/jb.45.6.555-564.1943. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van der Kooij D., Hijnen W. A. Nutritional versatility and growth kinetics of an Aeromonas hydrophila strain isolated from drinking water. Appl Environ Microbiol. 1988 Nov;54(11):2842–2851. doi: 10.1128/aem.54.11.2842-2851.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van der Kooij D., Oranje J. P., Hijnen W. A. Growth of Pseudomonas aeruginosa in tap water in relation to utilization of substrates at concentrations of a few micrograms per liter. Appl Environ Microbiol. 1982 Nov;44(5):1086–1095. doi: 10.1128/aem.44.5.1086-1095.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van der Kooij D., Visser A., Hijnen W. A. Growth of Aeromonas hydrophila at Low Concentrations of Substrates Added to Tap Water. Appl Environ Microbiol. 1980 Jun;39(6):1198–1204. doi: 10.1128/aem.39.6.1198-1204.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]