Importance of the iron-sulfur component and of the siroheme modification in the resting state of sulfite reductase.

Importance of the iron-sulfur component and of the siroheme modification in the resting state of sulfite reductase. J Inorg Biochem. 2019 Nov 18;203:110928 Authors: Brânzanic AMV, Ryde U, Silaghi-Dumitrescu R Abstract The active site of sulfite reductase (SiR) consists of an unusual siroheme-Fe4S4 assembly coupled via a cysteinate sulfur, and serves for multi-electron reduction reactions. Clear explanations have not been demonstrated for the reasons behind the choice of siroheme (vs. other types of heme) or for the single-atom coupling to an Fe4S4 center (as opposed to simple adjacency or to coupling via chains consisting of more than one atom). Possible explanations for these choices have previously been invoked, relating to the control of the spin state of the substrate-binding (siro)heme iron, modulation of the trans effect of the (Fe4S4-bound) cysteinate, or modulation of the redox potential. Reported here is a density functional theory (DFT) investigation of the structural interplay (in terms of geometry, molecular orbitals and magnetic interactions) between the siroheme and the Fe4S4 center as well as the importance of the covalent modifications within siroheme compared to the more common heme b, aiming to verify the role of the siroheme modification and of the Fe4S4 cluster at the SiR active site, with focus on previously-formulated hypotheses (geometrical/sterics, spin state, redox and electron-transfer control). A calibration of various DF...
Source: Journal of Inorganic Biochemistry - Category: Biochemistry Authors: Tags: J Inorg Biochem Source Type: research

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CONCLUSION: Extensive research have been carried out on various process for preparing Bortezomib and composition thereof. This type of dynamic research will clear the path for many generic players in the United States which lead in reduction of price of the composition and thereby enhancing global health care at cheaper prices. PMID: 32234004 [PubMed - as supplied by publisher]
Source: Recent Patents on Anti-Cancer Drug Discovery - Category: Cancer & Oncology Tags: Recent Pat Anticancer Drug Discov Source Type: research
FDA has granted Emergency Use Authorization (EUA) to Battelle's CCDS Critical Care Decontamination System for processing up to 80,000 respirator masks per system each day. CCDS employs concentrated, vapor-phase hydrogen peroxide (VPHP) for decontamination. The system has been validated to decontaminate masks of SARS-CoV-2, the company reported. The masks are placed on shelves inside a container, and a portable, external VPHP system is hooked up to the outside of container. The system was first envisioned by Battelle as part of a study commissioned by FDA in 2015. That study involved determining the feasibility of N95 respi...
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