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Hannibal, L., Tomasina, F., Capdevila, D.A., Demicheli, V., Totora, V., Alvarez-Paggi, D., Jemmerson, R., Murgida, D.H. and Radi, R. (2016) Alternative Conformations of Cytochrome c: Structure, Function, and Detection. Biochemistry, 55, 407-428.
https://doi.org/10.1021/acs.biochem.5b01385

has been cited by the following article:

• TITLE: Metallated Schiff-Base Macromolecules as Alternative Metalloprotein Electron Transfer Intermediates

  AUTHORS: Al C. Farao, Rachel Fanelwa Ajayi, Meryck Ward, Priscilla GL Baker

  KEYWORDS: Cytochrome-C, Macromolecule, Metallated, Metalloproteins, Schiff-Base

  JOURNAL NAME: Journal of Surface Engineered Materials and Advanced Technology, Vol.10 No.2, April 30, 2020

  ABSTRACT: In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention of electron transfer activity of the enzyme utilizing superior interfacial architecture. In this work a Schiff-base macromolecule has been synthesized by reflux of 2, 3-diaminonaphthalene and pyrrole-2-carboxaldehyde starting materials. The Schiff-base ligand was subsequently complexed with FeCl2?4H2O under reflux, to produce the Fe-Schiff-base complex. The Schiff-base ligand and Fe-Schiff-base complex were characterized using nuclear magnetic resonance (NMR) spectroscopy, Ultra Violet/Visible (UV/Vis) spectroscopy, Fourier transfer infrared resonance (FTIR) and electron energy loss spectroscopy (EELS) to confirm the structure of the synthesis products. NMR spectroscopy confirmed the imide linkage of Schiff-base formation as two symmetrical peaks at 8.1 and 7.7 ppm respectively. Comparison of starting materials and product spectra by UV/Vis spectroscopy confirmed the disappearance of the diaminonaphthalene peak at 250 nm as evidence of complete conversion to product. FTIR spectroscopy of the Schiff-base ligand confirmed the formation of the imine bond at 1595 cm-1. EELS spectra comparing FeCl2?4H2O and the Fe-Schiff-base complex, showed good agreement in the energy loss profiles associated with changes to the electronic arrangement of Fe d-orbitals. EDS clearly identified a spectral band for Fe (7 - 8 eV) in the Fe-Schiff-base complex. Electrochemical evaluation of the Fe-Schiff-base complex was compared to the electrochemical signature of denatured cytochrome-C using cyclic voltammetry and square wave voltammetry. The Fe2+/Fe3+ quasi-reversible behavior for iron in the metallated complex was observed at -0.430 V vs. Ag/AgCl, which is consistent with reference values for iron in macromolecular structures.