Nanosized non-proteinaceous complexes III and IV mimicking electron transfer of mitochondrial respiratory chain

Author(s)

Modenez, Iago A. ^[1] ; Macedo, Lucyano J. A. ^[1] ; Melo, Antonio F. A. A. ^{[1, 2]} ; Pereira, Andressa R. ^[3] ; Oliveira Jr, Osvaldo N. ; Crespilho, Frank N. ^[1]

Affiliation

^[1] Univ Sao Paulo, Sao Carlos Inst Chem, BR-13560970 Sao Carlos - Brazil

^[2] Fed Inst Educ Sci & Technol Piaui, Mat Engn Grad Program, Cent Campus, BR-64000040 Teresina, PI - Brazil

^[3] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13560590 Sao Carlos - Brazil

• Document type: Journal article
• Source: Journal of Colloid and Interface Science; v. 599, p. 198-206, OCT 2021.
• Web of Science Citations: 0

Abstract

Synthetic biology pursues the understanding of biological processes and their possible mimicry with artificial bioinspired materials. A number of materials have already been used to mimic the active site of simple redox proteins, including nanosized iron oxides due to their redox properties. However, the mimicry of membrane redox protein complexes is still a challenge. Herein, magnetic iron oxide nanoparticles (NPs), incorporated as non-proteinaceous complexes III and IV in a mitochondrial model membrane, catalyze electron transfer (ET) similarly to the natural complexes towards cytochrome c. The associated molecular mechanism is experimentally proven in solution and in a Langmuir-Blodgett film. A direct and entropy-driven ET, with rate constant of 2.63 +/- 0.05 L mol(-1) at 25 degrees C, occurs between the iron sites of the NPs and the cytochrome c heme group, not affecting the protein secondary and tertiary structures. This process requires an activation energy of 40.2 +/- 1.5 kJ mol(-1) resulting in an overall Gibbs free energy of similar to 55.3 kJ mol(-1). Furthermore, the protein-NP system is governed by electrostatic and non-polar forces that contribute to an associative mechanism in the transition state. Finally, the incorporated NPs in a model membrane were able to catalyze ET, such as the natural complexes in respiratory chain. This work presents an experimental approach demonstrating that inorganic nanostructured systems may behave as embedded proteins in the eukaryotic cells membrane, opening the way for more sophisticated and robust mimicry of membrane protein complexes. (C) 2021 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 19/12053-8 - High performance electrodes applied in organic batteries and in biofuel cell
• Grantee: Frank Nelson Crespilho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/22214-6 - Towards a convergence of technologies: from sensing and biosensing to information visualization and machine learning for data analysis in clinical diagnosis
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/03879-4 - EMU granted in the process 2013 / 14262-7 thematic project - DLS
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 17/20493-2 - Study of metalloenzymes through electrochemistry coupled to vibrational spectroscopy
• Grantee: Lucyano Jefferson Alves de Macêdo
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 19/15333-1 - Bio-photo-electrochemical hybrid cells for solar energy conversion
• Grantee: Frank Nelson Crespilho
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/00878-0 - Study of lipid rafts through the interaction between membrane models and chitosan and cholesterol oxidase
• Grantee: Andressa Ribeiro Pereira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral