[CuCN·Me3SnCN·0.5bpy] (bpy = 4,4‘-Bipyridine):  A Novel Supramolecular Assembly Involving the No Longer Unusual {Cu2(μ-CN)2(CN)2} Motif†

To date, most 3-D reconstructions of undecorated actin filaments have been obtained from actin filament paracrystal data (for refs, see 1,2). However, due to the fact that (a) the paracrystals may be several filament layers thick, and (b) adjacent filaments may sustantially interdigitate, these reconstructions may be subject to significant artifacts. None of these reconstructions has permitted unambiguous tracing or orientation of the actin subunits within the filament. Furthermore, measured values for the maximal filament diameter both determined by EM and by X-ray diffraction analysis, vary between 6 and 10 nm. Obviously, the apparent diameter of the actin filament revealed in the EM will critically depend on specimen preparation, since it is a rather flexible supramolecular assembly which can easily be bent or distorted. To resolve some of these ambiguities, we have explored specimen preparation conditions which may preserve single filaments sufficiently straight and helically ordered to be suitable for single filament 3-D reconstructions, possibly revealing molecular detail.

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Supramolecular Assembly of U(IV) Clusters and Superatoms

10.26434/chemrxiv.11860065 ◽

2020 ◽

Author(s):

Ian Colliard ◽

Gregory Morrosin ◽

Hans-Conrad zur Loye ◽

May Nyman

Keyword(s):

Quantum Dots ◽

Supramolecular Assembly ◽

Emergent Properties ◽

Organic Media ◽

Body Centered Cubic ◽

Cluster Anions ◽

Charge Balance ◽

Interpenetrating Networks ◽

Hierarchical Assembly ◽

Two Parameters

Superatoms are nanometer-sized molecules or particles that can form ordered lattices, mimicking their atomic counterparts. Hierarchical assembly of superatoms gives rise to emergent properties in superlattices of quantum-dots, p-block clusters, and fullerenes. Here, we introduce a family of uranium-oxysulfate cluster anions whose hierarchical assembly in water is controlled by two parameters; acidity and the countercation. In acid, larger LnIII (Ln=La-Ho) link hexamer (U6) oxoclusters into body-centered cubic frameworks, while smaller LnIII (Ln=Er-Lu &Y) promote linking of fourteen U6-clusters into hollow superclusters (U84 superatoms). U84 assembles into superlattices including cubic-closest packed, body-centered cubic, and interpenetrating networks, bridged by interstitial countercations, and U6-clusters. Divalent transition metals (TM=MnII and ZnII), with no added acid, charge-balance and promote the fusion of 10 U6 and 10 U-monomers into a wheel–shaped cluster (U70). Dissolution of U70 in organic media reveals (by small-angle Xray scattering) that differing supramolecular assemblies are accessed, controlled by TM-linking of U70-clusters.

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Effects of A6E Mutation on Protein Expression and Supramolecular Assembly of Yeast Asparagine Synthetase

Biology ◽

10.3390/biology10040294 ◽

2021 ◽

Vol 10 (4) ◽

pp. 294

Author(s):

Thunyarat Surasiang ◽

Chalongrat Noree

Keyword(s):

Protein Expression ◽

Stationary Phase ◽

Lymphoblastic Leukemia ◽

Energy Levels ◽

Supramolecular Assembly ◽

Asparagine Synthetase ◽

Gene Encoding ◽

Synthetase Deficiency ◽

Asparagine Synthetase Deficiency ◽

Intracellular Energy

Asparagine synthetase deficiency (ASD) has been found to be caused by certain mutations in the gene encoding human asparagine synthetase (ASNS). Among reported mutations, A6E mutation showed the greatest reduction in ASNS abundance. However, the effect of A6E mutation has not yet been tested with yeast asparagine synthetase (Asn1/2p). Here, we constructed a yeast strain by deleting ASN2 from its genome, introducing the A6E mutation codon to ASN1, along with GFP downstream of ASN1. Our mutant yeast construct showed a noticeable decrease of Asn1p(A6E)-GFP levels as compared to the control yeast expressing Asn1p(WT)-GFP. At the stationary phase, the A6E mutation also markedly lowered the assembly frequency of the enzyme. In contrast to Asn1p(WT)-GFP, Asn1p(A6E)-GFP was insensitive to changes in the intracellular energy levels upon treatment with sodium azide during the log phase or fresh glucose at the stationary phase. Our study has confirmed that the effect of A6E mutation on protein expression levels of asparagine synthetase is common in both unicellular and multicellular eukaryotes, suggesting that yeast could be a model of ASD. Furthermore, A6E mutation could be introduced to the ASNS gene of acute lymphoblastic leukemia patients to inhibit the upregulation of ASNS by cancer cells, reducing the risk of developing resistance to the asparaginase treatment.

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Ce IV 70 Oxosulfate Rings, Frameworks, Supramolecular Assembly, and Redox Activity**

Angewandte Chemie International Edition ◽

10.1002/anie.202016522 ◽

2021 ◽

Author(s):

Ian Colliard ◽

May Nyman

Keyword(s):

Supramolecular Assembly ◽

Redox Activity

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Hydrogen bonded network of 1,1-cyclobutanedicarboxylic acid (CBD) salts: Effect of amine backbone on supramolecular assembly

Journal of Molecular Structure ◽

10.1016/j.molstruc.2021.130025 ◽

2021 ◽

Vol 1232 ◽

pp. 130025

Author(s):

Mayuri Shaiwale ◽

Amar Ballabh

Keyword(s):

Supramolecular Assembly ◽

Cyclobutanedicarboxylic Acid ◽

Hydrogen Bonded

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Core-Substituted Naphthalene-diimides (cNDI) and Related Derivatives: Versatile Scaffold for Supramolecular Assembly and Functional Materials

Organic Materials ◽

10.1055/a-1530-0476 ◽

2021 ◽

Author(s):

Anurag Mukherjee ◽

Suhrit Ghosh

Keyword(s):

Photophysical Properties ◽

Supramolecular Assembly ◽

Functional Materials ◽

Building Blocks ◽

Short Review ◽

Molecular Engineering ◽

Organic Optoelectronics ◽

Naphthalene Diimide ◽

Naphthalene Diimides ◽

Derivatives Of

Naphthalene-diimide (NDI) derived building blocks have been explored extensively for supramolecular assembly as they exhibit attractive photophysical properties, suitable for applications in organic optoelectronics. Core-substituted derivatives of the NDI chromophore (cNDI) differ significantly from the parent NDI dye in terms of optical and redox properties. Adequate molecular engineering opportunities and substitution-dependent tunable optoelectronic properties make cNDI derivatives highly promising candidates for supramolecular assembly and functional material. This short review discusses recent development in the area of functional supramolecular assemblies based on cNDIs and related molecules.

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A polyelectrolyte based supramolecular assembly for ratiometric sensing of ATP with very high discrimination from pyrophosphate

Journal of Molecular Liquids ◽

10.1016/j.molliq.2021.115314 ◽

2021 ◽

pp. 115314

Author(s):

Vidya R. Singh ◽

Shrishti P. Pandey ◽

Prabhat K. Singh

Keyword(s):

Supramolecular Assembly ◽

Ratiometric Sensing ◽

High Discrimination ◽

Very High

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A reversible supramolecular assembly containing ionic interactions and disulfide linkages

New Journal of Chemistry ◽

10.1039/c4nj00895b ◽

2014 ◽

Vol 38 (11) ◽

pp. 5186-5189 ◽

Cited By ~ 1

Author(s):

Xinrong Lin ◽

Guilhem Godeau ◽

Mark W. Grinstaff

Keyword(s):

Redox Reaction ◽

Supramolecular Assembly ◽

Ionic Interactions ◽

Cooling Cycle ◽

Disulfide Linkages

A reversible ionic supramolecular assembly is described which can be disrupted and reformed by application of either a heating–cooling cycle or a mild redox reaction.

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