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

Channel Rhodopsins01:11

Channel Rhodopsins

2.6K
Most organisms use photoreceptors to sense and respond to light. Examples of photoreceptors include bacteriorhodopsins and bacteriophytochromes in some bacteria, phytochromes in plants, and rhodopsins in the photoreceptor cells of the vertebral retina. The light-sensitive property of these receptors is because of the bound chromophores, such as bilin in the phytochromes and retinal in the rhodopsins.
Rhodopsins belong to the family of cell surface proteins called G-protein coupled receptors,...
2.6K
G-Protein Gated Ion Channels01:21

G-Protein Gated Ion Channels

4.6K
GPCRs are primarily responsible for our sense of smell, taste, and vision.  The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory...
4.6K
ATP Driven Pumps I: An Overview01:27

ATP Driven Pumps I: An Overview

8.3K
ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
8.3K
Photoreceptors and Visual Pathways01:22

Photoreceptors and Visual Pathways

6.2K
At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category,...
6.2K
Anoxygenic Photosynthesis01:30

Anoxygenic Photosynthesis

58
Anoxygenic photosynthesis is a phototrophic process that captures light energy to drive carbon fixation without producing molecular oxygen. Unlike oxygenic photosynthesis, which utilizes water as an electron donor and releases oxygen, anoxygenic phototrophs use alternative electron donors such as hydrogen sulfide (H₂S), elemental sulfur (S⁰), or thiosulfate (S₂O₃²⁻). This process is carried out by diverse groups of bacteria, including purple bacteria, green...
58
The Z-Scheme of Electron Transport in Photosynthesis01:34

The Z-Scheme of Electron Transport in Photosynthesis

10.3K
The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of water molecules to produce oxygen. However, oxidation of water molecules is a thermodynamically unfavorable reaction and requires a strong oxidizing agent. This is accomplished by the first product of light reactions: oxidized P680 (or P680+), the most powerful oxidizing agent known in biology. The oxidized P680 that acquires an electron from the...
10.3K

You might also read

Related Articles

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

Sort by
Same author

Hydrostatic pressure spectroscopy reveals the adaptation of microbial rhodopsins to high-pressure environment.

Scientific reports·2026
Same author

Novel light-driven schizorhodopsins from Antarctic Minisyncoccota (Patescibacteria) and cyanobacteria.

Biophysical journal·2026
Same author

Light-harvesting by antenna-containing xanthorhodopsin from an Antarctic Pseudanabaenaceae cyanobacterium.

Communications biology·2025
Same author

Protonation-Enhanced Energy Transfer in Xanthorhodopsin Kin4B8.

The journal of physical chemistry letters·2025
Same author

Spin polarization driven by molecular vibrations leads to enantioselectivity in chiral molecules.

Science advances·2025
Same author

Apusomonad rhodopsins: A new family of ultraviolet to blue light-absorbing rhodopsin channels.

Proceedings of the National Academy of Sciences of the United States of America·2025

Related Experiment Video

Updated: Aug 2, 2025

Electromechanical Assessment of Optogenetically Modulated Cardiomyocyte Activity
12:52

Electromechanical Assessment of Optogenetically Modulated Cardiomyocyte Activity

Published on: March 5, 2020

8.3K

Converting a Natural-Light-Driven Outward Proton Pump Rhodopsin into an Artificial Inward Proton Pump.

María Del Carmen Marín1, Masae Konno1,2, Hiromu Yawo1

  • 1The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan.

Journal of the American Chemical Society
|April 21, 2023
PubMed
Summary
This summary is machine-generated.

Researchers converted an outward proton pump into an inward proton pump by altering just three amino acids in microbial rhodopsins. This discovery reveals key elements controlling proton transport direction in these essential membrane proteins.

More Related Videos

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
10:03

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

Published on: June 27, 2014

18.0K
Whole-cell Patch-clamp Recordings for Electrophysiological Determination of Ion Selectivity in Channelrhodopsins
08:39

Whole-cell Patch-clamp Recordings for Electrophysiological Determination of Ion Selectivity in Channelrhodopsins

Published on: May 22, 2017

17.2K

Related Experiment Videos

Last Updated: Aug 2, 2025

Electromechanical Assessment of Optogenetically Modulated Cardiomyocyte Activity
12:52

Electromechanical Assessment of Optogenetically Modulated Cardiomyocyte Activity

Published on: March 5, 2020

8.3K
Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
10:03

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

Published on: June 27, 2014

18.0K
Whole-cell Patch-clamp Recordings for Electrophysiological Determination of Ion Selectivity in Channelrhodopsins
08:39

Whole-cell Patch-clamp Recordings for Electrophysiological Determination of Ion Selectivity in Channelrhodopsins

Published on: May 22, 2017

17.2K

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Biophysics

Background:

  • Microbial rhodopsins are photoreceptive membrane proteins with varied light-regulated functions.
  • Most known microbial rhodopsins function as outward proton (H+) pumps, but inward H+ pumps have been recently identified.
  • Understanding the determinants of H+ transport direction is crucial for elucidating rhodopsin mechanisms.

Purpose of the Study:

  • To identify the minimum key amino acid residues responsible for determining the direction of proton (H+) transport in microbial rhodopsins.
  • To engineer an inward proton (H+) pump from an outward proton (H+) pump through targeted amino acid substitutions.

Main Methods:

  • Functional conversion study involving site-directed mutagenesis of a natural outward H+ pump (PspR).
  • Substitution of key amino acids in PspR with residues found in inward H+ pumping rhodopsins.
  • Spectroscopic analysis to investigate the H+ transport mechanism and pathway.

Main Results:

  • An artificial inward H+ pump was successfully constructed by mutating only three amino acid residues in PspR.
  • These three residues were identified as critical determinants for the directionality of H+ pumping.
  • Spectroscopic data confirmed an inward H+-accepting residue within the transport pathway and direct extracellular H+ uptake.

Conclusions:

  • A minimal set of three amino acid residues governs the switch between outward and inward proton (H+) transport in microbial rhodopsins.
  • This finding provides a fundamental understanding of ion transport directionality in microbial rhodopsins.
  • The identified key elements offer new insights into the mechanisms of various ion-pumping proteins.