This Article Full Text Full Text (PDF) Other Versions of this Article: AEM.00838-07v1 73/18/5782    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Delille, A. Articles by Humbert, F. Search for Related Content PubMed PubMed Citation Articles by Delille, A. Articles by Humbert, F. Agricola Articles by Delille, A. Articles by Humbert, F.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, September 2007, p. 5782-5788, Vol. 73, No. 18
0099-2240/07/$08.00+0     doi:10.1128/AEM.00838-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

In Situ Monitoring of the Nascent Pseudomonas fluorescens Biofilm Response to Variations in the Dissolved Organic Carbon Level in Low-Nutrient Water by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy

Laboratoire de Chimie Physique et Microbiologie pour l'Environnement, Nancy-Université, CNRS, 405, rue de Vandoeuvre, F-54600 Villers-lès-Nancy, France

Received 13 April 2007/ Accepted 10 July 2007

Drinking water quality management requires early warning tools which enable water supply companies to detect quickly and to forecast degradation of the microbial quality of drinking water during its transport throughout distribution systems. This study evaluated the feasibility of assessing, in real time, drinking water biostability by monitoring in situ the evolution of the attenuated total reflectance-Fourier transform infrared (ATR-FTIR) fingerprint of a nascent reference biofilm exposed to water being tested. For this purpose, the responses of nascent Pseudomonas fluorescens biofilms to variations in the dissolved organic carbon (DOC) level in tap water were monitored in situ and in real time by ATR-FTIR spectroscopy. Nascent P. fluorescens biofilms consisting of a monolayer of bacteria were formed on the germanium crystal of an ATR flowthrough cell by pumping bacterial suspensions in Luria-Bertani (LB) medium through the cell. Then they were exposed to a continuous flow of dechlorinated sterile tap water supplemented with appropriate amounts of sterile LB medium to obtain DOC concentrations ranging from 1.5 to 11.8 mg/liter. The time evolution of infrared bands related to proteins, polysaccharides, and nucleic acids clearly showed that changes in the DOC concentration resulted in changes in the nascent biofilm ATR-FTIR fingerprint within 2 h after exposure of the biofilm to the water being tested. The initial bacterial attachment, biofilm detachment, and regrowth kinetics determined from changes in the areas of bands associated with proteins and polysaccharides were directly dependent on the DOC level. Furthermore, they were consistent with bacterial adhesion or growth kinetic models and extracellular polymeric substance overproduction or starvation-dependent detachment mechanisms.

Published ahead of print on 20 July 2007.