caa a22 4500 445818239 CHVBK 20180317145235.0 cr unu---uuuuu 170323e20110101xx s 000 0 eng 10.1007/s00792-010-0341-4 doi (NATIONALLICENCE)springer-10.1007/s00792-010-0341-4 Probing the redox metabolism in the strictly anaerobic, extremely thermophilic, hydrogen-producing Caldicellulosiruptor saccharolyticus using amperometry [Elektronische Daten] [Natalie Kostesha, Karin Willquist, Jenny Emneus, Ed van Niel] Changes in the redox metabolism in the anaerobic, extremely thermophilic, hydrogen-forming bacterium Caldicellulosiruptor saccharolyticus were probed for the first time in vivo using mediated amperometry with ferricyanide as a thermotolerant external mediator. Clear differences in the intracellular electron flow were observed when cells were supplied with different carbon sources. A higher electrochemical response was detected when cells were supplied with xylose than with sucrose or glucose. Moreover, using the mediated electrochemical method, it was possible to detect differences in the electron flow between cells harvested in the exponential and stationary growth phases. The electron flow of C. saccharolyticus was dependent on the NADH- and reduced ferredoxin generation flux and the competitive behavior of cytosolic and membrane-associated oxidoreductases. Sodium oxamate was used to inhibit the NADH-dependent lactate dehydrogenase, upon which more NADH was directed to membrane-associated enzymes for ferricyanide reduction, leading to a higher electrochemical signal. The method is noninvasive and the results presented here demonstrate that this method can be used to accurately detect changes in the intracellular electron flow and to probe redox enzyme properties of a strictly anaerobic thermophile in vivo. Springer, 2010 Caldicellulosiruptor saccharolyticus nationallicence Lactate regulation nationallicence Anaerobiosis nationallicence Electrochemistry nationallicence Mediated amperometry nationallicence Ferricyanide nationallicence Kostesha Natalie Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads 345 East, 2800, Kgs. Lyngby, Denmark aut Willquist Karin Department of Applied Microbiology, Lund University, P.O. Box 124, 221 00, Lund, Sweden aut Emneus Jenny Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads 345 East, 2800, Kgs. Lyngby, Denmark aut van Niel Ed Department of Applied Microbiology, Lund University, P.O. Box 124, 221 00, Lund, Sweden aut Extremophiles Springer Japan 15/1(2011-01-01), 77-87 1431-0651 15:1<77 2011 15 792 https://doi.org/10.1007/s00792-010-0341-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00792-010-0341-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kostesha Natalie Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads 345 East, 2800, Kgs. Lyngby, Denmark aut NATIONALLICENCE 700 1- Willquist Karin Department of Applied Microbiology, Lund University, P.O. Box 124, 221 00, Lund, Sweden aut NATIONALLICENCE 700 1- Emneus Jenny Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads 345 East, 2800, Kgs. Lyngby, Denmark aut NATIONALLICENCE 700 1- van Niel Ed Department of Applied Microbiology, Lund University, P.O. Box 124, 221 00, Lund, Sweden aut NATIONALLICENCE 773 0- Extremophiles Springer Japan 15/1(2011-01-01), 77-87 1431-0651 15:1<77 2011 15 792 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer