Many minerals largely present in waters are involved in microbial growth, being essential like iron and zinc, or having toxic properties such as copper and manganese. Particular attention has been recently devoted to Legionella spp., an intracellular opportunistic pathogen ubiquitously present in the aquatic environment. L. pneumophila is responsible for severe pneumonia which occurs world-wide in susceptible persons inhaling aerosolised contaminated water. Interestingly, this bacterium is iron-dependent and requires iron superoxide dismutase for viability. In addition, recent studies documented a zinc-metalloprotease, the first identified type II effector necessary for optimal Legionella intracellular infection of amoebae. Copper interacts with hydroperoxide radicals and with the cell membranes, thus it is used as a biocide for controlling water microbial contamination. Lastly, manganese is regarded both as an essential and a toxic component of drinking water, but little is known on its role in bacteria surviving, including legionellae. The aim of this study was to establish the relationship between mineral content of a representative number of hot water samples and microbial contamination with specific reference to Legionella and Pseudomonas spp.
Influence of mineral content on Legionella and bacteria contamination in hot water distribution system / Marchesi, Isabella; Bargellini, Annalisa; A., Mansi; Borella, Paola. - In: MIKROÈLEMENTY V MEDICINE. - ISSN 1607-9957. - STAMPA. - 11:(2010), pp. 88-88. (Intervento presentato al convegno 4th International FESTEM Symposium on Trace Elements and Minerals in Medicine and Biology tenutosi a St. Petersburg, Russia nel 9-12 giugno 2010).