1. Bioelectrocatalysis Arkady A. Karyakin Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow, Russia

2. Bioelectrocatalysis is an acceleration of electrode reactions by biological catalysts Enzymes Whole cells

3. Applications of bioelectrocatalysis Fuel electrodes (biofuel cells) Biosensors Electrosysthesis

4. Enzyme bioelectrocatalysis

5. BIOELECTROCATALYSIS S2S2 P2P2

6. How to involve enzymes in bioelectrocatalysis? Use of mediators: Direct bioelectrocatalysis:

7. Direct bioelectrocatalysis if electrochemistry is determined by the catalyzed reaction or/and redox activity of biocatalyst

8. Oxidase catalysis

9. Redox activity of oxidases E ≈ -0.064 В (NHE) FAD

10. Mediated bioelectrocatalysis – II generation biosensors A. E. G. Cass, G. Davis, G. D. Francis, H. A. O. Hill, W. G. Aston, I. J. Higgins, E. V. Plotkin, L. D. L. Scott, and A. P. F. Turner, Analytical Chemistry 56, 667-671 (1984).

11. Glucose tests Accu-Chek Complete BG System Accu-Chek Complete BG System (Boehringer Mannheim) Accu-Chek Easy Accu-Chek Easy (Boehringer Mannheim) Accu-Chek Instant Accu-Chek Instant (Boehringer Mannheim) Accu-Chek Instant Plus Accu-Chek Instant Plus (Boehringer Mannheim) Autolet® II Clinisafe Autolet® II Clinisafe (Owen Mumford) Autolet® Lite Starter Pack Autolet® Lite Starter Pack (Owen Mumford) Blood Glucose Strips Blood Glucose Strips (Roche) Exatech® Exatech® (Medisense) Fingerstix Lancets Fingerstix Lancets (Bayer) Glucofilm™ Test Strips Glucofilm™ Test Strips (Bayer) Glucose Control Solution Glucose Control Solution (Roche) Glutose® Glutose® (Roche) Lifescan One Touch® Basic™ System Lifescan One Touch® Basic™ System (Johnson & Johnson) Medipoint Blood Lancets Medipoint Blood Lancets (Medipoint) Monolet Lancet Monolet Lancet (Kendall-Sherwood) Soft-Touch® II Soft-Touch® II (Boehringer Mannheim) Softclix Softclix (Roche) Unilet Long-Body™ Lancets Unilet Long-Body™ Lancets (Owen Mumford) Unistik™-2 Unistik™-2 (Owen Mumford)

12. B.A. Gregg, A. Heller. Anal. Chem. 62 (1990) 258 Mediated bioelectrocatalysis – II generation biosensors

13. Wiring of glucose oxidase Heller, A. Physical Chemistry Chemical Physics 2004, 6, 209-216. E = -0.195 mV (Ag|AgCl)

14. Glucose test Therasense: 0.3 µL of blood

15. Dehydrogenase catalysis > 500 enzymes

16. NAD + |NADH redox reaction  the lowest potential in aerobic organisms;  on bare electrodes the overvoltages exceed 1 Volt.

17. Methylene Blue Methylene Green Azur A Toluidine Blue Brilliant Cresyl Blue Neurtal Red Thionine

18. Electropolymerized azines: a new class of electroactive polymers Toluidine Blue E, V 0.1mA/cm -0.4 0.40.8 2

19. Hypothesis on polyazine structure A.A. Karyakin, E.E. Karyakina, H.-L. Schmidt. Electroanalysis (1999) 11 149.

20. Catalysis of NAD + reduction and NADH oxidation 0.1 mM NADH 0.1 mM NAD +

21. Equilibrium NAD + |NADH potential A.A.Karyakin, Yu.N.Ivanova, E.E.Karyakina Electrochem. Commun. (2003) 5, 677-80

22. Direct enzyme bioelectrocatalysis

23. Protein electroactivity Cytochrome C S.R. Betso, M.H. Klapper, L.B. Anderson. J. Am. Chem. Soc. 94 (1972) 8197-204. M.R. Tarasevich, V.A. Bogdanovskaya. Bioelectrochem. Bioenerg. 3 (1976) 589-95. M.J. Eddowes, H.A.O. Hill. J. Chem. Soc., Chem. Commun. (1977) 71 P. Yeh, T. Kuwana. Chem. Lett. (1977) 1145-8 Niki K, Yagi T, Inokuchi H, Kimura K. JACS 101 (1979) 3335-40.

24. Promoters for protein electroactivity M.J. Eddowes, H.A.O. Hill. J. Chem. Soc., Chem. Commun. (1977) 71 P. Yeh, T. Kuwana. Chem. Lett. (1977) 1145-8 gold ē ē

25. Berezin I. V., Bogdanovskaya V. A., Varfolomeev S.D., M.R. Tarasevich, A.I Yaropolov. Dokl.Akad.Nauk SSSR (Proc. Acad. Sci.) 240 (1978) 615-618 Direct bioelectrocatalysis E st = 1.2 V

26. Enzymes for direct bioelectrocatalysis Iron-sulfur clusters HEM PQQ Others

27. A.I Yaropolov, V. Malovik, Varfolomeev S.D., Berezin I. V. Dokl.Akad.Nauk SSSR (Proc. Acad. Sci.) 249 (1979) 1399-401 Direct bioelectrocatalysis

28. A.I. Yaropolov, A.A. Karyakin, S.D. Varfolomeyev, I.V. Berezin. Bioelectrochem. Bioenerg. 12 (1984) 267-77 Direct bioelectrocatalysis

29. BIOELECTROCATALYSIS by Th. roseopersicina hydrogenase (1), (3) - H 2 ; (2) - Ar (3) - without active enzyme (Yaropolov A.I., Karyakin A.A., Varfolomeyev S.D., Berezin I.V. Bioelectrochem. & Bioenergetics 12 (1984) 267-277)

30. Equilibrium hydrogen potential (100% energy conversion) Nernst’ equation for

31. How to involve oxidases in bioelectrocatalysis? surface pre-treatment; using of promoters; surface design by conducting polymers.

32. Fundamentals of direct bioelectrocatalysis Investigations of enzyme redox centers Redox switching of enzyme activity

33. Direct bioelectrocatalysis by intact cells

34. Principal structure of bacterial cells

35. Inorganic ion reducing bacteria Shewanella putrefaciens Lactate as electron donor Insoluble Fe 3+ as electron acceptor

36. Electroactivity of Shewanella putrefaciens A – air exposed cells B – air exposed with lactate C – no air, but at + 200 mV D – at +200 mV with lactate Kim, B. H.; Ikeda, T.; Park, H. S.; Kim, H. J.; Hyun, M. S.; Kano, K.; Takagi, K.; Tatsumi, H. Biotechnology Techniques 1999, 13, 475-478.

37. Geobacter sulfurreducens on graphite electrode Bond, D. R.; Lovley, D. R. Applied And Environmental Microbiology 2003, 69, 1548.

38. Advantages of bioelectrocatalysis: a possibility for electrochemistry of complex organic reactions; high efficiency at room temperature and moderate overvoltages; achieve high specificity. Disadvantages: inherent instability, large dimensions of biological catalysts.