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Cyclodextrin-Containing Polymers for Gene Delivery 总被引:2,自引:0,他引:2
Mark E. Davis Nathalie C. Bellocq 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):17-22
Cyclodextrin-containing polymers are now being explored as vehicles for delivering nucleic acids into cells. The structures of the cyclodextrin-containing polycations affect the nucleic acid delivery efficiencies and their toxicities. Of interest is the fact that the cyclodextrin-containing polymers reveal lower toxicities than polymers that lack the cyclodextrins. The cyclodextrins endow the nucleic acid delivery vehicles with the ability to be modified by compounds that form inclusion complexes with the cyclodextrins, and these modifications can be performed without disruption of the polymer-nucleic acid interactions. Thus, cyclodextrin-containing polymers provide unique properties for gene delivery. 相似文献
24.
Lancelot N Elbayed K Raya J Piotto M Briand JP Formaggio F Toniolo C Bianco A 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(6):1317-1323
A tetra- and a hepta-homopeptide from the C(alpha)-tetrasubstituted Aib (alpha-aminoisobutyric acid) residue were covalently linked to the POEPOP resin by the fragment-condensation approach. The conformational preferences of the two model peptides were determined for the first time on a solid support by means of high-resolution magic angle spinning NMR spectroscopy. The results obtained indicate that the Aib homopeptides adopt a regular 3(10)-helical structure even when they are covalently bound to a polymeric matrix, and thus confirm the remarkable conformational stability of the peptides rich in this amino acid. An ATR-FTIR spectroscopic investigation, performed in parallel, also confirmed that these polymer-bound peptides do indeed adopt a helical conformation. The results of this study open the possibility to exploit the peptide-resin conjugates based on C(alpha)-tetrasubstituted alpha-amino acids as helpful, structurally organized templates in molecular recognition studies or as catalysts in asymmetric synthesis. 相似文献
25.
George N Pick H Vogel H Johnsson N Johnsson K 《Journal of the American Chemical Society》2004,126(29):8896-8897
The specific and covalent labeling of fusion proteins with synthetic molecules opens up new ways to study protein function in the living cell. Here we present a novel method that allows for the specific and exclusive extracellular labeling of proteins on the surfaces of live cells with a large variety of synthetic molecules including fluorophores, protein ligands, or quantum dots. The approach is based on the specific labeling of fusion proteins of acyl carrier protein with synthetic molecules through post-translational modification catalyzed by phosphopantetheine transferase. The specificity and versatility of the labeling should allow it to become an important tool for studying and manipulating cell surface proteins and for complementing existing approaches in cell surface engineering. 相似文献
26.
Patrick Gredin Gwenaël Corbel Jonathan P. Wright Nathalie Dupont Ariel de Kozak 《无机化学与普通化学杂志》2003,629(11):1960-1964
Ba3Cu2Al2F16 is monoclinic: a = 7.334(1)Å, b = 5.320(2)Å, c = 16.022(1)Å, β = 96.34(1)°, Z = 2. Its crystal structure was solved in the space group P21 (No. 4) from synchrotron X‐ray single crystal data using 2685 unique reflections (2639 with Fo/σ(Fo) > 4). The final R factor is 0.044. The structure consists of a succession along the c‐axis of the cell of three layers of two different kinds of sheets developing in the (a, b) plane. The first one, formulated [(AlF5)2]∞4— and hereafter named A, is built up from infinite cis‐chains of aluminium‐fluorine octahedra [AlF6], linked by two vertices and distanced by a. The second one, formulated [Cu2AlF11]∞4— and named B, is bidimensional. It is constituted of distorted copper‐fluorine octahedra [CuF6], linked by edges, which form infinite chains interconnected by three vertices of isolated [AlF6] octahedra. The stacking sequence of the sheets is (A, B, B)∞. The barium ions, 12‐coordinated, are inserted between the sheets. The crystal structure of Ba3Cu2Al2F16 is closely related to that of Ba4Cu2Al3F21. Only the proportion and the stacking sequence of the two kinds of sheets in the c‐direction differ, according to two different compositions and two different symmetries. 相似文献
27.
Trens P Tanchoux N Galarneau A Fajula F 《The journal of physical chemistry. B》2005,109(34):16415-16420
In the present work, the corresponding states principle is proposed as a new approach to clarify the comparison between adsorption-desorption isotherms obtained on porous solids. The applicability of this principle at the capillary critical point in adsorption-desorption isotherms is demonstrated. Deviations of the Clausius-Clapeyron curves in reduced coordinates are interpreted in terms of polarizability, and those are perfectly correlated using analogous Pitzer acentric factors in confined environments. New acentric factors are proposed to take confinement effects in mesoporous materials into account. Enthalpic excesses during capillary condensation could be predicted, and those are supported by calorimetric experiments. 相似文献
28.
Yam CM Pradier CM Salmain M Fischer-Durand N Jaouen G 《Journal of colloid and interface science》2002,245(1):204-207
Fourier transform infrared reflection-absorption spectroscopy (FT-IRRAS) was successively used to monitor the covalent immobilization of biotin molecules onto a planar gold substrate covered with a self-assembled monolayer of cystamine and to transduce the molecular recognition of avidin and biotin. This detection was greatly facilitated and made selective by the labeling of avidin and of biotin with various transition metal carbonyl probes. The binding of avidin to the surface was optimized by blocking the nonspecific binding sites by adsorption of an unrelated protein, bovine serum albumin. This work exemplifies the feasibility of detecting biomolecular associations involving molecules of any size at a liquid/solid interface by using a simple and accessible surface analysis technique. 相似文献
29.
Phosphatidylinositol-specific phospholipase C (PI-PLC) enzymes are a virulence factor in many Gram-positive organisms. The specific activity of the Bacillus thuringiensis PI-PLC is significantly increased by adding phosphatidylcholine (PC) to vesicles composed of the substrate phosphatidylinositol, in part because the inclusion of PC reduces the apparent Kd for the vesicle binding by as much as 1000-fold when comparing PC-rich vesicles to PI vesicles. This review summarizes (i) the experimental work that localized a site on BtPI-PLC where PC is bound as a PC choline cation—Tyr-π complex and (ii) the computational work (including all-atom molecular dynamics simulations) that refined the original complex and found a second persistent PC cation—Tyr-π complex. Both complexes are critical for vesicle binding. These results have led to a model for PC functioning as an allosteric effector of the enzyme by altering the protein dynamics and stabilizing an ‘open’ active site conformation. 相似文献
30.
Manal Diab Ana Mateo Joumada El Cheikh Zeinab El Hajj Mohamed Haouas Alireza Ranjbari Vincent Gurineau David Touboul Nathalie Leclerc Emmanuel Cadot Daoud Naoufal Carles Bo Sbastien Floquet 《Molecules (Basel, Switzerland)》2022,27(22)
Herein we report the synthesis of a new class of compounds associating Keggin and Dawson-type Polyoxometalates (POMs) with a derivative of the anionic decahydro-closo-decaborate cluster [B10H10]2− through aminopropylsilyl ligand (APTES) acting as both a linker and a spacer between the two negatively charged species. Three new adducts were isolated and fully characterized by various NMR techniques and MALDI-TOF mass spectrometry, notably revealing the isolation of an unprecedented monofunctionalized SiW10 derivative stabilized through intramolecular H-H dihydrogen contacts. DFT as well as electrochemical studies allowed studying the electronic effect of grafting the decaborate cluster on the POM moiety and its consequences on the hydrogen evolution reaction (HER) properties. 相似文献