J Chem Phys
September 2025
Proton-coupled electron transfer (PCET) is pervasive throughout chemistry, biology, and physics. Over the last few decades, we have developed a general theoretical formulation for PCET that includes the quantum mechanical effects of the electrons and transferring protons, including hydrogen tunneling, as well as the reorganization of the environment and the donor-acceptor fluctuations. Analytical rate constants have been derived in various well-defined regimes.
View Article and Find Full Text PDFThe impact of the electrode-electrolyte interface on the performance of zinc-metal batteries remains unclear. We propose a gradient SEI strategy, where the outer organic layer inhibits corrosion and the inner inorganic layer regulates Zn (002) crystal growth. This work offers new insights into the critical role of SEI layers.
View Article and Find Full Text PDFRibonucleotide reductase (RNR) is essential for DNA synthesis and repair in all living organisms. The mechanism of RNR requires long-range radical transport through a proton-coupled electron transfer (PCET) pathway spanning two different protein subunits. Herein, the direct PCET reaction between the interfacial tyrosine residues, Y356 and Y731, is investigated with a vibronically nonadiabatic theory that treats the transferring proton and all electrons quantum mechanically.
View Article and Find Full Text PDFEarly spliceosome assembly can occur through an intron-defined pathway, whereby U1 and U2 small nuclear ribonucleoprotein particles (snRNPs) assemble across the intron. Alternatively, it can occur through an exon-defined pathway, whereby U2 binds the branch site located upstream of the defined exon and U1 snRNP interacts with the 5' splice site located directly downstream of it. The U4/U6.
View Article and Find Full Text PDFThis study describes a novel species of (Squamata, Agamidae) from the lower valley of the Dadu River of the Sichuan Province of Western China based on its distinct morphological features and molecular evidence. sp. nov.
View Article and Find Full Text PDFJ Phys Chem Lett
February 2024
The enzyme ribonucleotide reductase, which is essential for DNA synthesis, initiates the conversion of ribonucleotides to deoxyribonucleotides via radical transfer over a 32 Å pathway composed of proton-coupled electron transfer (PCET) reactions. Previously, the first three PCET reactions in the α subunit were investigated with hybrid quantum mechanical/molecular mechanical (QM/MM) free energy simulations. Herein, the fourth PCET reaction in this subunit between C439 and guanosine diphosphate (GDP) is simulated and found to be slightly exoergic with a relatively high free energy barrier.
View Article and Find Full Text PDFRisk Manag Healthc Policy
March 2023
Purpose: Quality control circle (QCC) has acquired success in many fields in healthcare industry as a process management tool, whereas its efficacy in surgical antimicrobial prophylaxis (SAP) remains unknown. This study aimed to implement QCC interventions to improve the appropriateness of SAP.
Methods: A QCC activity team was established to grasp the current situation of SAP in clean surgery procedure, set target, formulate corresponding countermeasures and implement and review them in stages.
Ribonucleotide reductase (RNR) regulates DNA synthesis and repair in all organisms. The mechanism of RNR requires radical transfer over a proton-coupled electron transfer (PCET) pathway spanning ∼32 Å across two protein subunits. A key step along this pathway is the interfacial PCET reaction between Y356 in the β subunit and Y731 in the α subunit.
View Article and Find Full Text PDFBiochem Biophys Res Commun
September 2022
The basic helix-loop-helix (bHLH) family is one of the most conserved transcription factor families that plays an important role in regulating cell growth, differentiation and tissue development. Typically, members of this family form homo- or heterodimers to recognize specific motifs and activate transcription. MyoD is a vital transcription factor that regulates muscle cell differentiation.
View Article and Find Full Text PDFRibonucleotide reductase (RNR) catalyzes the reduction of ribonucleotides to deoxyribonucleotides and is critical for DNA synthesis and repair in all organisms. Its mechanism requires radical transfer along a ∼32 Å pathway through a series of proton-coupled electron transfer (PCET) steps. Previous simulations suggested that a glutamate residue (E623) mediates the PCET reaction between two stacked tyrosine residues (Y730 and Y731) through a proton relay mechanism.
View Article and Find Full Text PDFJ Int Med Res
January 2022
We report the first case of a woman with Behcet's disease (BD) with multiple hand ulcers secondary to coninfection by and resulting in necrotizing fasciitis. She had a long history of BD including long courses of prednisone and immunosuppressants. The patient was hospitalized for multiple superficial ulcers, swelling, and infection of the hands.
View Article and Find Full Text PDFThe genome exists as an organized, three-dimensional (3D) dynamic architecture, and each cell type has a unique 3D genome organization that determines its cell identity. An unresolved question is how cell type-specific 3D genome structures are established during development. Here, we analyzed 3D genome structures in muscle cells from mice lacking the muscle lineage transcription factor (TF), MyoD, versus wild-type mice.
View Article and Find Full Text PDFChin Med J (Engl)
October 2021
Background: Ankylosing spondylitis (AS) is a common chronic progressive rheumatic disease. The aim of this study was to explore factors influencing abnormal bone mineral density (BMD) in young and middle-aged patients with AS.
Methods: From July 2014 to August 2018, hospitalized patients with AS and health examinees in the health examination center of our clinics, ranging in age from 20 to 50 years, were monitored.
Ribonucleotide reductase (RNR) is an essential enzyme in DNA synthesis for all living organisms. It reduces ribonucleotides to the corresponding deoxyribonucleotides by a reversible radical transfer mechanism. The active form of Ia RNR is composed of two subunits, α and β, which form an active asymmetric αβ complex.
View Article and Find Full Text PDFPurpose: Long noncoding RNAs (lncRNAs) are important regulators of diverse biological functions. However, an extensive in-depth analysis of their expression profile and function in mammalian eyes is still lacking. Here we describe comprehensive landscapes of stage-dependent and tissue-specific lncRNA expression in the mouse eye.
View Article and Find Full Text PDFARF suppresses aberrant cell growth upon c-Myc overexpression by activating p53 responses. Nevertheless, the precise mechanism by which ARF specifically restrains the oncogenic potential of c-Myc without affecting its normal physiological function is not well understood. Here, we show that low levels of c-Myc expression stimulate cell proliferation, whereas high levels inhibit by activating the ARF/p53 response.
View Article and Find Full Text PDFThe PTEN tumor suppressor is a lipid phosphatase that has a central role in regulating the phosphatidylinositol-3-kinase (PI3K) signal transduction cascade. Nevertheless, the mechanism by which the PTEN activity is regulated in cells needs further elucidation. Although previous studies have shown that ubiquitination of PTEN can modulate its stability and subcellular localization, the role of ubiquitination in the most critical aspect of PTEN function, its phosphatase activity, has not been fully addressed.
View Article and Find Full Text PDFJ Biol Chem
February 2012
It is well accepted that the Mdm2 ubiquitin ligase acts as a major factor in controlling p53 stability and activity in vivo. Although several E3 ligases have been reported to be involved in Mdm2-independent p53 degradation, the roles of these ligases in p53 regulation in vivo remain largely unknown. To elucidate the physiological role of the ubiquitin ligase ARF-BP1, we generated arf-bp1 mutant mice.
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