Electrical wiring of viable Gluconobacter oxydans cells with a flexible osmium-redox polyelectrolyte

An application of a flexible polyvinylimidazole osmium functionalised polymer for efficient electrical wiring of whole Gluconobacter oxydans cells is described. The performance of the redox polymer as a mediator for intact bacterial cells was tested with glucose, ethanol and glycerol, typical substrates of the periplasmically localised PQQ-dependent membrane bound dehydrogenases. The efficiency of the electron transfer with the osmium redox polymer was compared with that of a soluble mediator (ferricyanide). Some basic bioelectrochemical characteristics, including I-max, K-m(app), inactivation constants and sensitivities were estimated for the mentioned substrates. The sensitivity profile for the tested substrates as well as the pH dependencies correspond well with the sensitivity profile for ferricyanide as soluble mediator. Significant stability differences for the substrates were found. (C) 2004 Elsevier B.V. All rights reserved.