title: Electrochemical activity and bacterial diversity of natural marine biofilm in laboratory closed-systems.
abstract: Even if a widely shared mechanism actually does not exist, it is now generally accepted that, in aerobic conditions, marine electrochemically active biofilms (MEABs) induce faster oxygen reduction on stainless steel immersed in seawater. This phenomenon has been widely studied, but nearly all the experiments found in literature have been conducted in open-systems (i.e. experimental environments where seawater is constantly renewed). In this work we tried to obtain, in open circuit and potentiostatic conditions, MEABs in different laboratory closed-systems without water renewal (mesocosms), in order to verify the relationship between electrochemical activity and biofilm composition. The diversity of the microbial populations of biofilms obtained by our new kind of approach was examined by the DGGE technique (denaturing gradient gel electrophoresis). MEABs were obtained in all the mesocosms from 2000 to 2 L, showing in some cases electrochemical performances comparable to those of open-systems, and a very high genetic variability. Our DGGE results underline the difficulty in finding a correlation between electrochemical activity and composition of microbial populations.
authors.affiliation: Istituto di Scienze Marine-Consiglio Nazionale delle Ricerche (ISMAR-CNR), Via de Marini 6, 16149 Genoa, Italy. marco.faimali@ismar.cnr.it
authors.forename: Marco
authors.initials: M
authors.lastname: Faimali
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Chelossi
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pavanello
authors.forename: Alessandro
authors.initials: A
authors.lastname: Benedetti
authors.forename: Ilse
authors.initials: I
authors.lastname: Vandecandelaere
authors.forename: Paul
authors.initials: P
authors.lastname: De Vos
authors.forename: Peter
authors.initials: P
authors.lastname: Vandamme
authors.forename: Alfonso
authors.initials: A
authors.lastname: Mollica
mesh_terms: D001420:Bacteria, Aerobic / Q000145:classification* / Q000502:physiology* / Q000528:radiation effects; D018441:Biofilms; D018929:Cell Culture Techniques / Q000379:methods*; D004574:Electromagnetic Fields; D009792:Oceans and Seas; D014871:Water Microbiology