The combination of photoredox and enzymatic catalysis in a cyclic reaction network enables enantioselectivity control photochemical processes.

Complementing enzymes in their native environment with either homogeneous or heterogeneous catalysts is challenging due to the sea of functionalities present within a cell. To supplement these efforts, artificial metalloenzymes are drawing attention as they combine attractive features both and enzymes. Herein we show that such hybrid consisting metal cofactor, cell-penetrating module, protein scaffold taken up into HEK-293T cells where catalyze uncaging hormone. This bioorthogonal reaction...

NADH mimics (mNADHs) have been shown to accelerate and orthogonally activate ene reductase-catalyzed reactions. However, existing regeneration methods of NAD(P)H fail for mNADHs. Catalysis with artificial metalloenzymes based on streptavidin (Sav) variants a biotinylated iridium cofactor enable mNADH formate. This can be coupled asymmetric reduction α,β-unsaturated compounds, because the protective compartmentalization organometallic cofactor. With 10 mol % mNAD+, preparative scale reaction...

Enzymes typically depend on either NAD(P)H or FADH2 as hydride source for reduction purposes. In contrast, organometallic catalysts most often rely isopropanol formate to generate the reactive moiety. Here we show that incorporation of a Cp*Ir cofactor possessing biotin moiety and 4,7-dihydroxy-1,10-phenanthroline into streptavidin yields an NAD(P)H-dependent artificial transfer hydrogenase (ATHase). This ATHase (0.1 mol%) catalyzes imine with 1 mM NADPH (2 mol%), which can be concurrently...

GaAs/Al 0.3 Ga 0.7 As quantum wells (QWs) grown on (411)A-oriented GaAs substrates by molecular beam epitaxy (MBE) showed extremely flat interfaces over a macroscopic area (about 200 µm φ) even for the case of no growth interruption, which is mainly due to intrinsically large migration atoms and layer in step-flow mode (411)A plane. Photoluminescence linewidths at 4.2K were almost same as or better than narrowest reported GaAs/AlGaAs GaAs/AlAs QWs (100) with interruption each...

Cyclic oligochalcogenides (COCs) are emerging as promising systems to penetrate cells. Clearly better than and different the reported diselenolanes epidithiodiketopiperazines, we introduce benzopolysulfanes (BPS), which show efficient delivery, insensitivity inhibitors of endocytosis, compatibility with substrates large proteins. This high activity coincides reactivity, selectively toward thiols, exceeding exchange rates disulfides under tension. The result is a dynamic-covalent network...

Abstract The chemical modification of proteins serves as a fundamental tool for understanding biological processes and enables the design biofunctional materials. Among available methodologies, photochemical strategies have garnered significant attention because their remarkable biocompatibility precise spatiotemporal reaction control. Developing novel reactions tailored to specific applications necessitates comprehensive photoreactive properties, including catalyst structures, appropriate...

We have performed Raman studies of lithium niobate from 293 to 1224 K with special emphasis upon quantitative analysis the quasielastic scattering 0--50 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$. find that complete spectrum, including both ``wing'' and two lowest-frequency ${A}_{1}$-symmetry optical phonons, can be fitted spectral distribution function predicted for a system relaxing self-energy; when this is done all parameters vary slowly monotonically temperature. The coupling parameter...

GaAs/AlAs quantum wires (QWRs) were found to be naturally formed by a regularly corrugated AlAs/GaAs interface and flat in an AlAs/GaAs/AlAs well with width of 3.3 nm grown on (775)B GaAs substrate molecular beam epitaxy. The lateral period vertical amplitude the corrugation 12 1.2 nm, respectively. QWRs side extremely high density 8×10 5 QWRs/cm. A photoluminescence peak at λ=715 from cross section about 12×3 2 showed polarization degree ( I ∥ - ⊥ ) / + = 0.11 very small full half maximum...

The upper branch of the polariton dispersion curve has been experimentally obtained by measuring thermal emission spectra thin films LiF at oblique angles. formulation based on virtual mode theory is given for determination relation. from resonance frequency and width due to 0 T H which lowest higher region than LO frequency. Measurements have performed temperatures 420°K 650° angles ranging 45° 80°. results agree fairly well with theory.

GaAs/AlGaAs quantum wells (QWs) were grown on (411)A-oriented GaAs substrates by molecular beam epitaxy (MBE). Photoluminescence linewidths at 4.2 K are almost the same as narrowest reported so far for QWs (100)-oriented with growth interruption heterointerfaces. Furthermore, only one sharp peak was observed each QW (411) substrate over whole area of wafer (10 mm×10 mm), in contrast three splitted luminescence peaks kind (100) MBE interruption. This result implies that effectively atomically...

Cyclic oligochalcogenides are emerging as powerful tools to penetrate cells. With disulfide ring tension maximized, selenium chemistry had be explored next enhance speed and selectivity of dynamic covalent exchange on the way into cytosol. We show that diseleno lipoic acid (DiSeL) delivers a variety relevant substrates. DiSeL-driven uptake artificial metalloenzymes enables bioorthogonal fluorophore uncaging within Binding bicyclic peptide, phalloidin, actin fibers evinces targeted delivery...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSurface-enhanced Raman scattering from model acrylic adhesive systemsF. J. Boerio, P. Hong, Clark, and Y. OkamotoCite this: Langmuir 1990, 6, 4, 721–727Publication Date (Print):April 1, 1990Publication History Published online1 May 2002Published inissue 1 April 1990https://pubs.acs.org/doi/10.1021/la00094a002https://doi.org/10.1021/la00094a002research-articleACS PublicationsRequest reuse permissionsArticle Views283Altmetric-Citations40LEARN ABOUT...

Photochemistry usually functions on a one‐photon‐one‐electron basis, leading to unstable radical intermediates that must be intercepted rapidly allow efficient product formation. This can render multi‐electron reductions and enantioselective reactions particularly challenging. In this minireview, we discuss recent advances in the area of photo‐driven transfer with particular focus our own work reductive amination synthesis amines by combined photoredox enzyme catalysis. Polarity‐matched...

While photocatalysts have been recognized as powerful and environmentally friendly catalysts, harnessing their reactivity still remains challenging. On account of the distinctive reaction compartment that protein scaffolds provide for incorporated metal complex, artificial metalloenzymes (ArMs) can improve catalytic rates stereochemical selectivity. In present study, we developed a photo-driven ArM by incorporating DNA photo-switch [Ru(bpy)2dppz]2+ (1), into an apo-form riboflavin-binding...

This study was conducted to verify the effectiveness of Anterior Support Screw (AS2) for unstable femoral trochanteric fractures.

Abstract Cross‐regulation of complex biochemical reaction networks is an essential feature living systems. In a biomimetic spirit, we report on our efforts to program the temporal activation artificial metalloenzyme via cross‐regulation by natural enzyme. presence urea, urease slowly releases ammonia that reversibly inhibits transfer hydrogenase. Addition acid, which acts as fuel, allows maintain system out equilibrium.

The bacterial chemotaxis protein of Desulfovibrio vulgaris DcrH (DcrH-Hr) functions as an O2-sensing protein. This has a hemerythrin-like domain that includes nonheme diiron center analogous to the hemerythrin (Hr) family. Interestingly, O2 affinity DcrH-Hr is 3.3 × 106 M–1, value 25-fold higher than Pectinaria gouldii Hr. high arises from fast association ligand with (kon = 5.3 108 M–1 s–1), which made possible by hydrophobic tunnel accelerates passage site. Furthermore, autoxidation...

In wind tunnel studies on the flow around bluff bodies accompanying a large separated wake, walls of test section severely effect characteristics them. Proposed in this paper is correction formula for wall effects upon two-dimensional (2-D) unsteady incompressible fluid bodies. The proposed derived from numerical results with discrete vortex method 2-D flows an inclined flat plate, square cylinder, and also elliptic cylinder located between two parallel walls. It found that present estimates...