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• Bacterial motility can be modulated by the use of chemoeffectors in porous systems. • Tactic reactions allow to increase the bacterial degradation of a pollutant distance source. • Pyrene metabolites were detected in column effluents as a result of bacterial degradation. • These new findings have implications for bioremediation in groundwater. One of the main problems in contaminated soils is that many toxic substances, such as PAHs, which are found in areas close to aquifers and groundwater, are difficult to access and degrade via traditional methods of remediation. The use of controlled bacterial mobility through chemotaxis has been shown to be efficient in increasing the dispersion of pollutant-degrading organisms, increasing the biodegradation rates of pollutants. In this study, using percolation columns as model aquifers, the mobilization of the Pseudomonas putida G7 strain to a distant pyrene source was demonstrated using γ-aminobutyric acid and artificial root exudates as strong chemoeffectors. An increase in the biodegradation rates of the pollutant was observed relative to columns in which the tactic effector was not added. The presence of different metabolites was detected via a fraction collector associated with an HPLC system, providing evidence for the cometabolic capacity of strain G7. The use of chemotactic organisms can be an effective approach for the remediation of polluted sediments associated with aquifers and groundwaters, offering new possibilities for the treatment of contaminated aqueous areas. [Display omitted] [ABSTRACT FROM AUTHOR]

• A MALDI-TOF MS database for identification of water-related bacteria was created. • The Drinking Water Library (DWL) is composed of 319 MALDI-TOF MS bacteria profiles. • The DWL incorporates 44 new genera absent in the Bruker's database. • The DWL improved identification for water isolates by up to of 76%. • The DWL contributes to the routine microbiological control of drinking water. According to the European Directives (UE) 2020/2184 and 2009/54/EC, which establishes the sanitary criteria for water intended for human consumption in Europe, water suitable for human consumption must be free of the bacterial indicators Escherichia coli, Clostridium perfringens and Enterococcus spp. Drinking water is also monitored for heterotrophic bacteria, which are not a human health risk, but can serve as an index of bacteriological water quality. Therefore, a rapid, accurate, and cost-effective method for the identification of these colonies would improve our understanding of the culturable bacteria of drinking water and facilitate the task of water management by treatment facilities. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is potentially such a method, although most of the currently available mass spectral libraries have been developed in a clinical setting and have limited environmental applicability. In this work, a MALDI-TOF MS drinking water library (DWL) was defined and developed by targeting bacteria present in water intended for human consumption. This database, made up of 319 different bacterial strains, can contribute to the routine microbiological control of either treated drinking water or mineral bottled water carried out by water treatment and distribution operators, offering a faster identification rate compared to a clinical sample-based library. The DWL, made up of 96 bacterial genera, 44 of which are not represented in the MALDI-TOF MS bacterial Bruker Daltonics (BDAL) database, was found to significantly improve the identification of bacteria present in drinking water. [Display omitted] [ABSTRACT FROM AUTHOR]