Related Experiment Video
Updated: Feb 17, 2026
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
18.4K
Variation in LOV Photoreceptor Activation Dynamics Probed by Time-Resolved Infrared Spectroscopy
James N Iuliano1, Agnieszka A Gil1, Sergey P Laptenok2
1Department of Chemistry, Stony Brook University , Stony Brook, New York 11794, United States.
Biochemistry
|December 15, 2017
Summary
Light-oxygen-voltage (LOV) proteins use flavin mononucleotide (FMN) for blue light sensing. This study reveals conserved FMN adduct formation but divergent downstream signaling in LOV photoreceptors, crucial for optogenetics.
Area of Science:
- Biochemistry
- Photobiology
- Molecular Biology
Background:
- Light-oxygen-voltage (LOV) domains are blue light sensors utilizing flavin mononucleotide (FMN).
- Their modularity enables applications in optogenetics and optobiology through fusion to output domains.
- Understanding LOV domain dynamics is key to designing novel light-controlled systems.
Purpose of the Study:
- To investigate the ultrafast to microsecond dynamics of three full-length LOV domain photoreceptors.
- To compare the conserved FMN adduct formation pathway with variable signaling kinetics.
- To link spectral and kinetic differences to specific output functions of LOV domains.
Main Methods:
- Transient infrared spectroscopy was employed to study LOV-STAS (YtvA), LOV-HTH (EL222), and LOV-histidine kinase (LovK).
- Spectroscopic analysis covered timescales from subpicoseconds to hundreds of microseconds.
- Kinetic and vibrational spectral changes post-adduct formation were analyzed.
Main Results:
- A conserved pathway for cysteine adduct formation from the FMN triplet state was observed across all tested LOV proteins.
- Slight variations in the rate of adduct formation were noted.
- Significant differences in post-adduct vibrational spectra and kinetics were found, correlating with distinct output domains.
Conclusions:
- The initial light-induced signaling cascade involving FMN adduct formation is highly conserved in LOV photoreceptors.
- Subsequent large-scale structural changes and signaling kinetics vary significantly (orders of magnitude) based on the specific output domain.
- These findings provide insights into the structure-function relationships of LOV-based optogenetic tools.
Related Concept Videos
01:09Infrared (IR) Spectroscopy: Overview
5.2K
When electromagnetic radiation passes through a material, atoms or molecules transition from a lower to a higher energy state by absorbing radiation corresponding to the energy difference between the two states. The absorption of infrared (IR) radiation causes transitions between vibrational energy levels in a molecule. Therefore, IR spectroscopy is a useful analytical tool for determining the molecular structure of molecules.
Different compounds display unique properties due to their...
Different compounds display unique properties due to their...
5.2K
01:22Photoreceptors and Visual Pathways
9.4K
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,...
9.4K
01:16IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
3.1K
A covalently bonded heteronuclear diatomic molecule can be modeled as two vibrating masses connected by a spring. The vibrational frequency of the bond can be expressed using an equation derived from Hooke's law, which describes how the force applied to stretch or compress a spring is proportional to the displacement of the spring. In this case, the atoms behave like masses, and the bond acts like a spring.
According to Hooke's law, the vibrational frequency is directly proportional to...
According to Hooke's law, the vibrational frequency is directly proportional to...
3.1K
02:00Photoreceptors and Plant Responses to Light
28.6K
Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.
28.6K
01:24IR Spectroscopy: Molecular Vibration Overview
4.9K
When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
4.9K
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
3.0K
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this...
3.0K