title: Electrical wiring of live, metabolically enhanced Bacillus subtilis cells with flexible osmium-redox polymers.
abstract: The present study explores genetic engineering of the respiratory chain and the application of two different flexible osmium redox polymers to achieve efficient electric communication between the gram-positive organism Bacillus subtilis and an electrode. Poly(1-vinylimidazole)(12)-[Os-(4,4'-dimethyl-2,2'-bipyridyl)(2)Cl(2)](+/2+) (osmium redox polymer I) and poly(vinylpyridine)-[Os-(N,N'-methylated-2,2'-biimidazole)(3)](2+/3+) (osmium redox polymer II) were investigated for efficient electrical "wiring" of viable gram-positive bacterial cells to electrodes. Using a B. subtilis strain that overproduces succinate/quinone oxidoreductase (respiratory complex II), we were able to improve the current response several fold using succinate as substrate, in both batch and flow analysis modes, and using gold and graphite electrodes. The efficiency of the osmium redox polymer, working as electron transfer mediator between the cells and the electrode, was compared with that of a soluble mediator (hexacyanoferrate). The results demonstrated that mediators did not have to pass the cytosolic membrane to bring about an efficient electronic communication between bacterial cells with a thick cell wall and electrodes.
authors.affiliation: Department of Biochemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
authors.forename: Vasile
authors.initials: V
authors.lastname: Coman
authors.forename: Tobias
authors.initials: T
authors.lastname: Gustavsson
authors.forename: Arnonas
authors.initials: A
authors.lastname: Finkelsteinas
authors.forename: Claes
authors.initials: C
authors.lastname: von Wachenfeldt
authors.forename: Cecilia
authors.initials: C
authors.lastname: Hägerhäll
authors.forename: Lo
authors.initials: L
authors.lastname: Gorton
mesh_terms: D001412:Bacillus subtilis / Q000166:cytology* / Q000378:metabolism; D055664:Electrochemical Techniques; D004566:Electrodes; D042963:Electron Transport Complex II / Q000235:genetics; D005818:Genetic Engineering; D009992:Osmium; D011108:Polymers
chemical_list: D011108:Polymers; C478189:respiratory complex II; D009992:Osmium; D042963:Electron Transport Complex II