Video Experimental Relacionado
Updated: Jan 6, 2026
![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)
10:01
Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
12.6K
Cómo la [FeFe]-hidrogenasa facilita la transferencia bidireccional de protones
Moritz Senger1, Viktor Eichmann1, Konstantin Laun1
1Experimental Molecular Biophysics, Department of Physics , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany.
Journal of the American Chemical Society
|October 4, 2019
Resumen
Los investigadores investigaron la transferencia de protones en las [FeFe]-hidrogenasas, enzimas cruciales para la conversión del hidrógeno. Descubrieron que la transferencia de protones es continua en el estado reducido, facilitada por residuos de aminoácidos específicos como la arginina R148.
Área de la Ciencia:
- La bioquímica
- La bioenergía
- Enzimología
Sus antecedentes:
- Las hidrogenasas son metalloenzimas que catalizan la interconversión de hidrógeno molecular (H2) y protones.
- Las [FeFe]-hidrogenasas son conocidas por sus altas tasas de rotación de H2, inspirando la producción biomimética de H2.
- Los mecanismos de transferencia de protones en las [FeFe]-hidrogenasas siguen siendo poco conocidos a pesar de las extensas investigaciones sobre su sitio activo.
Objetivo del estudio:
- Para aclarar el mecanismo de la transferencia catalítica de protones en las [FeFe]-hidrogenasas.
- Investigar los cambios dinámicos en la red de enlaces de hidrógeno durante la fotorreducción.
- Para identificar los residuos de aminoácidos específicos involucrados en la transferencia de protones.
Principales métodos:
- Se utilizó la espectroscopia de diferencias infrarrojas in situ.
- Se estudió la [FeFe]-hidrogenasa de Chlamydomonas reinhardtii.
- Se evaluaron los cambios dinámicos en la red de enlaces de hidrógeno durante la fotorreducción.
Principales resultados:
- La transferencia de protones aparece deteriorada en el estado oxidado (Hox) pero continua en el estado reducido (Hred).
- Se identificaron cambios transitorios en la protonación del ácido glutámico (E141) y de la arginina (R148).
- La transferencia bidireccional de protones es facilitada por estos residuos específicos.
Conclusiones:
- La transferencia continua de protones ocurre en el estado reducido de las [FeFe]-hidrogenasas.
- La arginina R148 y el ácido glutámico E141 juegan un papel crucial en la facilitación de la transferencia de protones.
- Este estudio proporciona información molecular sobre los mecanismos de retransmisión de protones en las hidrogenasas.
Videos de Conceptos Relacionados
01:32Chemiosmosis
111.1K
Oxidative phosphorylation is a highly efficient process that generates large amounts of adenosine triphosphate (ATP), the basic unit of energy that drives many cellular processes. Oxidative phosphorylation involves two processes— the electron transport chain and chemiosmosis.
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons...
111.1K
02:13Reduction of Alkenes: Catalytic Hydrogenation
13.8K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
13.8K
01:28Electron Transport Chains
111.3K
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...
The ETC is comprised of...
111.3K
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.8K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.8K
01:22Chemiosmosis and ATP Synthesis
1.7K
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...
1.7K
01:04Hydrogen Bonds
12.9K
A hydrogen bond is formed when a weakly positive hydrogen atom already bonded to one electronegative atom (for example, the oxygen in the water molecule) is attracted to another electronegative atom from another polar molecule, such as water (H2O), hydrogen fluoride (HF), or ammonia (NH3). The huge electronegativity difference between the H atom (2.1) and the atom to which it is bonded (4.0 for an F atom, 3.5 for an O atom, or 3.0 for an N atom), combined with the very small size of an H atom...
12.9K