Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Electron Transport Chain Components01:29

Electron Transport Chain Components

The electron transport chain (ETC) is a crucial metabolic pathway that facilitates energy conversion in prokaryotic and eukaryotic cells. In eukaryotes, the ETC comprises four membrane-associated protein complexes in the inner mitochondrial membrane. In prokaryotes, the ETC in the plasma membrane can vary in composition, with fewer or different complexes depending on the organism and environmental conditions. These complexes transfer electrons from electron donors, such as NADH and FADH2, to...
Chemiosmosis and ATP Synthesis01:22

Chemiosmosis and ATP Synthesis

The electron transport chain is a critical component of cellular respiration, occurring in the inner mitochondrial membrane. It facilitates the transfer of high-energy electrons from reduced cofactors NADH and FADH₂ to molecular oxygen, the final electron acceptor. This transfer of electrons through a series of protein complexes is tightly coupled to the translocation of protons across the membrane, generating a proton gradient essential for ATP synthesis.Electron Flow and Proton...
Mechanical Protein Functions01:58

Mechanical Protein Functions

Proteins perform many mechanical functions in a cell. These proteins can be classified into two general categories- proteins that generate mechanical forces and proteins that are subjected to mechanical forces. Proteins providing mechanical support to the structure of the cell, such as keratin, are subjected to mechanical force, whereas proteins involved in cell movement and transport of molecules across cell membranes, such as an ion pump, are examples of generating mechanical force. 
Energy to Drive Translocation01:37

Energy to Drive Translocation

Mitochondrial protein import is powered by two distinct energy sources: ATP hydrolysis and electrochemical potential across the inner membrane. Newly synthesized precursors are bound by cytosolic chaperones of the Hsp70 family, which guide them to the import receptors on the mitochondrial surface. Utilizing the energy of ATP hydrolysis, Hsp70 chaperones transfer these precursors to the TOM receptors on the mitochondrial outer membrane.
Generally, polypeptides are unfolded by two distinct...
Electron Transport Chains01:28

Electron Transport Chains

The final stage of cellular respiration is oxidative phosphorylation that consists of two steps: the electron transport chain and chemiosmosis. The electron transport chain is a set of proteins found in the inner mitochondrial membrane in eukaryotic cells. Its primary function is to establish a proton gradient that can be used during chemiosmosis to produce ATP and generate electron carriers, such as NAD+ and FAD, that are used in glycolysis and the citric acid cycle.
The ETC is comprised of...
Protein Diffusion in the Membrane01:24

Protein Diffusion in the Membrane

Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion experiment where mouse and human cells were fused, resulting in hybrid cells. When the human and mouse cells fused, the specific membrane proteins on human and mouse cells were marked with the red and green-fluorescent markers, respectively. Initially, the red and green fluorescence was located on the respective hemisphere of the cell. As time...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Multistep electron tunneling through tryptophans in the KatG bifunctional peroxidase monitored by a nonperturbing spin probe.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

Next generation protein-corrole bio-assemblies provide effective tumoricidal treatment in a metastatic triple-negative breast cancer model.

bioRxiv : the preprint server for biology·2026
Same author

Electron Transport through a Tryptophan Quadruplex in a Dimeric Azurin Construct.

The journal of physical chemistry. B·2026
Same author

Oxidizable amino acids around cytochrome P450 hemes.

Journal of inorganic biochemistry·2025
Same author

Real-Time Tracking of Photoinduced Metal-Metal Bond Formation in a d<sup>8</sup>d<sup>8</sup> Di-Iridium Complex by Vibrational Coherence and Femtosecond Stimulated Raman Spectroscopy.

Journal of the American Chemical Society·2025
Same author

Systemic HER3 ligand-mimicking nanobioparticles enter the brain and reduce intracranial tumour growth.

Nature nanotechnology·2025
Same journal

Aspect Ratio and Quantum Confinement Tunable Giant Two-Photon Absorption from 1D CsPbI<sub>3</sub> Perovskite Nanorods.

Chemical physics letters·2023
Same journal

Identification of possible binding modes of SARS-CoV-2 spike <i>N</i>-terminal domain for ganglioside GM1.

Chemical physics letters·2022
Same journal

Infrared spectra of the SARS-CoV-2 spike receptor-binding domain: Molecular dynamics simulations.

Chemical physics letters·2022
Same journal

Constructing high-accuracy theoretical Raman spectra of SARS-CoV-2 spike proteins based on a large fragment method.

Chemical physics letters·2022
Same journal

Unraveling the binding mechanism of the active form of Remdesivir to RdRp of SARS-CoV-2 and designing new potential analogues: Insights from molecular dynamics simulations.

Chemical physics letters·2022
Same journal

Multiple protonation states in ligand-free SARS-CoV-2 main protease revealed by large-scale quantum molecular dynamics simulations.

Chemical physics letters·2022
See all related articles

Related Experiment Video

Updated: Jun 16, 2026

Examining the Conformational Dynamics of Membrane Proteins in situ with Site-directed Fluorescence Labeling
11:55

Examining the Conformational Dynamics of Membrane Proteins in situ with Site-directed Fluorescence Labeling

Published on: May 29, 2011

Electron Flow through Proteins.

Harry B Gray1, Jay R Winkler

  • 1Beckman Institute, California Institute of Technology, Pasadena, California 91125.

Chemical Physics Letters
|February 18, 2010
PubMed
Summary
This summary is machine-generated.

Electron transfer occurs over long distances in biological systems. This study shows electron tunneling and hopping mechanisms enable rapid electron transfer in proteins, crucial for photosynthesis and respiration.

More Related Videos

F&#246;rster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features
07:09

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features

Published on: March 16, 2022

Introduction to Solid Supported Membrane Based Electrophysiology
19:56

Introduction to Solid Supported Membrane Based Electrophysiology

Published on: May 11, 2013

Related Experiment Videos

Last Updated: Jun 16, 2026

Examining the Conformational Dynamics of Membrane Proteins in situ with Site-directed Fluorescence Labeling
11:55

Examining the Conformational Dynamics of Membrane Proteins in situ with Site-directed Fluorescence Labeling

Published on: May 29, 2011

F&#246;rster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features
07:09

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features

Published on: March 16, 2022

Introduction to Solid Supported Membrane Based Electrophysiology
19:56

Introduction to Solid Supported Membrane Based Electrophysiology

Published on: May 11, 2013

Area of Science:

  • Biochemistry
  • Biophysics
  • Molecular Biology

Background:

  • Electron transfer is fundamental to biological energy conversion processes like photosynthesis and respiration.
  • These processes involve metal cofactors separated by significant molecular distances within proteins.
  • Understanding the mechanisms of long-range electron transfer is key to deciphering these biological functions.

Purpose of the Study:

  • To investigate the mechanisms and kinetics of electron transfer over long distances (20 Å) in metalloproteins.
  • To compare the efficiency of single-step electron tunneling versus multi-step electron hopping.
  • To elucidate the role of intervening amino acid residues in facilitating electron transfer.

Main Methods:

  • Utilized laser flash-quench triggering methods to initiate and monitor electron transfer.
  • Studied electron transfer in ruthenium-modified cytochromes and blue copper proteins.
  • Investigated electron transfer in both solution and crystalline states of the proteins.
  • Analyzed multi-step tunneling (hopping) through specific amino acid residues, such as tryptophan.

Main Results:

  • Demonstrated that Fe(II) to Ru(III) and Cu(I) to Ru(III) electron tunneling occurs on the microsecond timescale over 20 Å.
  • Confirmed that electron transfer can happen efficiently in both solution and crystal forms.
  • Showed that 20-Å hole hopping through tryptophan is significantly faster (two orders of magnitude) than single-step electron tunneling.
  • Established the feasibility of long-range redox equivalent transfer via multi-step tunneling.

Conclusions:

  • Electron tunneling and hopping are viable mechanisms for long-range electron transfer in biological systems.
  • Multi-step hopping, particularly through specific residues like tryptophan, can be more efficient than direct tunneling for long distances.
  • These findings provide insights into the fundamental principles governing electron transport in proteins, relevant to photosynthesis and respiration.