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Cordas, C. M., N. M. T. Lourenco, P. Vidinha, CAM Afonso, S. Barreiros, L. P. Fonseca, and J. M. S. Cabral. "New conducting biomaterial based on Ion Jelly (R) technology for development of a new generation of biosensors." New Biotechnology. 25 (2009): S138-S139. AbstractWebsite
Cordas, C. M., J. Wilton, T. Cardoso, F. Folgosa, AS Pereira, and P. Tavares. "Electrochemical behaviour of Dps-a mini-ferritin." European Biophysics Journal with Biophysics Letters. 40 (2011): 181. AbstractWebsite
Folgosa, F., C. M. Cordas, J. A. Santos, AS Pereira, JJG Moura, P. Tavares, and I. Moura. "New spectroscopic and electrochemical insights on a class I superoxide reductase: evidence for an intramolecular electron-transfer pathway." Biochemical Journal. 438 (2011): 485-494. AbstractWebsite

SORs (superoxide reductases) are enzymes involved in bacterial resistance to reactive oxygen species, catalysing the reduction of superoxide anions to hydrogen peroxide. So far three structural classes have been identified. Class I enzymes have two ironcentre-containing domains. Most studies have focused on the catalytic iron site (centre II), yet the role of centre I is poorly understood. The possible roles of this iron site were approached by an integrated study using both classical and fast kinetic measurements, as well as direct electrochemistry. A new heterometallic form of the protein with a zinc-substituted centre I, maintaining the iron active-site centre II, was obtained, resulting in a stable derivative useful for comparison with the native all-iron from. Second-order rate constants for the electron transfer between reduced rubredoxin and the different SOR forms were determined to be 2.8 x 10(7) M(-1) . s(-1) and 1.3 x 10(6) M(-1) . s(-1) for SOR(Fe(IIII)-Fe(II)) and for SOR(Fe(IIII)-Fe(III)) forms respectively, and 3.2 x 10(6) M(-1) s(-1) for the SOR(Zn(II)-Fe(III)) form. The results obtained seem to indicate that centre I transfers electrons from the putative physiological donor rubredoxin to the catalytic active iron site (intramolecular process). In addition, electrochemical results show that conformational changes are associated with the redox state of centre I, which may enable a faster catalytic response towards superoxide anion. The apparent rate constants calculated for the SOR-mediated electron transfer also support this observation.

Carvalho, R. N. L., R. M. Almeida, JJG Moura, N. T. Lourenço, L. J. P. Fonseca, and C. M. Cordas. "Sandwich-Type Enzymatic Fuel Cell Based on a New Electro-Conductive Material - Ion Jelly." ChemistrySelect. 1.20 (2016): 6546-6552. AbstractWebsite
Matias, S. C., N. M. T. Lourenço, L. J. P. Fonseca, and C. M. Cordas. "Comparative Electrochemical Behavior of Cytochrome c on Aqueous Solutions Containing Choline-Based Room Temperature Ionic Liquids." ChemistrySelect. 2.27 (2017): 8701-8705. AbstractWebsite
Samhan-Arias, A. K., S. Fortalezas, C. M. Cordas, I. Moura, JJG Moura, and C. Gutierrez-Merino. "Cytochrome b5 reductase is the component from neuronal synaptic plasma membrane vesicles that generates superoxide anion upon stimulation by cytochrome c." Redox Biology. 15 (2018): 109-114. AbstractWebsite
Rosa, V., A. P. S. Gaspari, F. Folgosa, C. M. Cordas, P. Tavares, T. Santos-Silva, S. Barroso, and T. Avilés. "Imine ligands based on ferrocene: Synthesis, structural and Mössbauer characterization and evaluation as chromogenic and electrochemical sensors for Hg2+." New Journal of Chemistry. 42.5 (2018): 3334-3343. AbstractWebsite
Teixeira, L. R., C. M. Cordas, M. P. Fonseca, N. E. C. Duke, P. R. Pokkuluri, and C. A. Salgueiro. "Modulation of the Redox Potential and Electron/Proton Transfer Mechanisms in the Outer Membrane Cytochrome OmcF From Geobacter sulfurreducens." Frontiers in Microbiology. 10 (2020). AbstractWebsite
Ramanaiah, S. V., C. M. Cordas, S. Matias, and L. P. Fonseca. "In situ electrochemical characterization of a microbial fuel cell biocathode running on wastewater." Catalysts. 11.7 (2021). AbstractWebsite