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Protein-to-protein electron transfer (ET) is a critical process in biological chemistry for which fundamental understanding is expected to provide a wealth of applications in biotechnology. Investigations of protein-protein ET systems in reductive activation of artificial cofactors introduced into proteins remains particularly challenging because of the complexity of interactions between the cofactor and the system contributing to ET. In this work, we construct an artificial protein-protein ET system, using heme oxygenase (HO), which is known to catalyze the conversion of heme to biliverdin. HO uses electrons provided from NADPH/cytochrome P450 reductase (CPR) through protein-protein complex formation during the enzymatic reaction. We report that a FeIII(Schiff-base), in the place of the active-site heme prosthetic group of HO, can be reduced by NADPH/CPR. The crystal structure of the Fe(10-CH2CH2COOH-Schiff-base)·HO composite indicates the presence of a hydrogen bond between the propionic acid carboxyl group and Arg-177 of HO. Furthermore, the ET rate from NADPH/CPR to the composite is 3.5-fold faster than that of Fe(Schiff-base)·HO, although the redox potential of Fe(10-CH2CH2COOH-Schiff-base)·HO (−79 mV vs. NHE) is lower than that of Fe(Schiff-base)·HO (+15 mV vs. NHE), where NHE is normal hydrogen electrode. This work describes a synthetic metal complex activated by means of a protein-protein ET system, which has not previously been reported. Moreover, the result suggests the importance of the hydrogen bond for the ET reaction of HO. Our Fe(Schiff-base)·HO composite model system may provide insights with regard to design of ET biosystems for sensors, catalysts, and electronics devices.
What else can I help you with?
How is the natural anti-coagulant protein C activated?
Protein C is activated when thrombin binds to thrombomodulin on the surface of endothelial cells.
What enzyme is activated by cAMP?
Protein kinase A (PKA) is activated by cAMP (cyclic adenosine monophosphate). Once activated, PKA plays a crucial role in many cellular processes by phosphorylating target proteins.
Human caspases can be activated by?
irreparable DNA damage or protein misfolding.
What protein is produced when gene is activated through transcription and translation?
The protein coded for in the DNA transcribed ad then translated.
Which of the substances below is a protein that can hold several other relay proteins as it binds to an activated membrane receptor?
An example of a protein that can hold several other relay proteins as it binds to an activated membrane receptor is an adaptor protein. Adaptor proteins play a crucial role in mediating protein-protein interactions and signaling cascades by bringing together different signaling molecules or relay proteins at the cell membrane after receptor activation.
When a gene or genes which code for units which make up a protein are turned on by the Cell they are said to be?
Activated.
When a gene or genes which code for units which make up a protein are turned on by the Cell they are said to be what?
Activated.
Is iron a protein?
No, it's a metal.
What activates protein kinase A?
Protein kinase A is activated by the binding of cyclic AMP (cAMP) to its regulatory subunits, causing the catalytic subunits to be released and become active.
What is the mechanism by which protein kinase A is activated by the second messenger?
Protein kinase A is activated by the second messenger through a process called phosphorylation. When the second messenger binds to the regulatory subunit of protein kinase A, it causes a conformational change that releases the catalytic subunit. This released catalytic subunit is then able to phosphorylate target proteins, leading to various cellular responses.
What has the author Susan Randall written?
Susan Randall has written: 'Interactions among the mitogen-activated protein kinase cascades and the identification of a novel cdc2-related protein kinase'
Are there metal fragments in air activated hand warmers and why?
Yes, air-activated hand warmers typically contain a mix of iron powder, water, salt, activated carbon, and vermiculite. When the packet is opened and exposed to air, the iron powder oxidizes, releasing heat as a byproduct. The metal fragments are necessary for this exothermic reaction to occur and produce heat.
