National Institute of Biology kindly invites you to attend the lecture:

"An essential role for UshA in processing of extracellular flavin electron shuttles by Shewanella oneidensis."

by Dr. Elizabeth Covington from the National Institute of Biology, Department of Biotechnology and Systems Biology

The lecture will take place on Thursday, the 19th January 2012, at 15:00 p.m. in the Lecture Hall B3 of the Biological Centre, Večna pot 111, Ljubljana.

Abstract: The facultative anaerobe Shewanella oneidensis can reduce a number of insoluble extracellular metals, making it a valuable tool for environmental bioremediation and production of electrical current by microbial fuel cells. The mechanisms that allow extracellular metal reduction are only gradually becoming clear. Direct adsorption of cells to the metal surface is not necessary, and it has been shown that S. oneidensis releases low concentrations of flavins into the surrounding medium to act as extracellular electron shuttles.

However, the mechanism of flavin release by Shewanella remains unknown. A transposon mutagenesis screen to identify mutants deficient in extracellular flavin accumulation led to discovery that the 5´-nucleotidase UshA hydrolyzes periplasmic FAD to generate the electron shuttles riboflavin and flavin mononucleotide (FMN). The surprising implication that FAD is secreted into the periplasmic space has been further developed with the recent identification of a putative FAD transporter.