title: A rapid electrochemical procedure for the detection of Hg(0) produced by mercuric-reductase: application for monitoring Hg-resistant bacteria activity.
abstract: In this work, gold microelectrodes are employed as traps for the detection of volatilized metallic mercury produced by mercuric reductase (MerA) extracted from an Hg-resistant Pseudomonas putida strain FB1. The enzymatic reduction of Hg (II) to Hg (0) was induced by NADPH cofactor added to the samples. The amount of Hg(0) accumulated on the gold microelectrode surface was determined by anodic stripping voltammetry (ASV) after transferring the gold microelectrode in an aqueous solution containing 0.1 M HNO(3) + 1 M KNO(3). Electrochemical measurements were combined with spectrofluorometric assays of NADPH consumption to derive an analytical expression for the detection of a relative MerA activity of different samples with respect to that of P. putida. The method developed here was employed for the rapid determination of MerA produced by bacteria harbored in soft tissues of clams (Ruditapes philippinarum), collected in high Hg polluted sediments of Northern Adriatic Sea in Italy.
authors.affiliation: Dipartimento di Scienze Molecolari e Nanosistemi, Università Cà Foscari Venezia, Calle Larga S. Marta 2137 - 30127 Venice, Italy. dario.battistel@unive.it
authors.forename: Dario
authors.initials: D
authors.lastname: Battistel
authors.forename: Franco
authors.initials: F
authors.lastname: Baldi
authors.forename: Davide
authors.initials: D
authors.lastname: Marchetto
authors.forename: Michele
authors.initials: M
authors.lastname: Gallo
authors.forename: Salvatore
authors.initials: S
authors.lastname: Daniele
mesh_terms: D000818:Animals; D049872:Bivalvia; D024881:Drug Resistance, Bacterial; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D006046:Gold; D007558:Italy; D008628:Mercury / Q000032:analysis* / Q000378:metabolism*; D008839:Microelectrodes; D009249:NADP / Q000032:analysis; D010088:Oxidoreductases / Q000032:analysis / Q000378:metabolism*; D016958:Pseudomonas putida / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D009249:NADP; D006046:Gold; D010088:Oxidoreductases; C021551:mercuric reductase; D008628:Mercury