37 research outputs found
Low Loading Pt Cathode Catalysts for Direct Methanol Fuel Cell Derived from the Particle Size Effect
Low Loading Pt Cathode Catalysts for Direct
Methanol Fuel Cell Derived from the Particle Size
Effec
Protein-Scaffold Directed Nanoscale Assembly of T Cell Ligands: Artificial Antigen Presentation with Defined Valency, Density, and Ratio
Tuning
antigen presentation to T cells is a critical step in investigating
key aspects of T cell activation. However, existing technologies have
a limited ability to control the spatial and stoichiometric organization
of T cell ligands on 3D surfaces. Here, we developed an artificial
antigen presentation platform based on protein scaffold-directed assembly
that allows fine control over the spatial and stoichiometric organization
of T cell ligands on a 3D yeast cell surface. Using this system, we
observed that the T cell activation threshold on a 3D surface is independent
of peptide-major histocompatibility complex (pMHC) valency but instead
is determined by the overall pMHC surface density. When intercellular
adhesion molecule 1 (ICAM-1) was coassembled with pMHC, it enhanced
antigen recognition sensitivity by 6-fold. Further, T cells responded
with different magnitudes to varying ratios of pMHC and ICAM-1 and
exhibited a maximum response at a ratio of 15% pMHC and 85% ICAM-1,
introducing an additional parameter for tuning T cell activation.
This protein scaffold-directed assembly technology is readily transferrable
to acellular surfaces for translational research as well as large-scale
T-cell manufacturing
Engineering Compositionally Uniform Yeast Whole-Cell Biocatalysts with Maximized Surface Enzyme Density for Cellulosic Biofuel Production
In
recent decades, whole-cell biocatalysis has played an increasingly
important role in the food, pharmaceutical, and energy sector. One
promising application is the use of ethanologenic yeast displaying
minicellulosomes on the cell surface to combine cellulose hydrolysis
and fermentation into a single step for consolidated bioprocessing.
However, cellulosic ethanol production using existing yeast whole-cell
biocatalysts (yWCBs) has not reached industrial feasibility due to
their inefficient cellulose hydrolysis. As prior studies have demonstrated
enzyme density on the yWCB surface to be one of the most important
parameters for enhancing cellulose hydrolysis, we sought to maximize
this parameter at both the population and single-cell levels in yWCBs
displaying tetrafunctional minicellulosomes. At the population level,
enzyme density is limited by the presence of a nondisplay population
constituting 25–50% of all cells. In this study, we identified
the cause to be plasmid loss and successfully eliminated the nondisplay
population to generate compositionally uniform yWCBs. At the single-cell
level, we demonstrate that enzyme density is limited by molecular
crowding, which hinders minicellulosome assembly. By adjusting the
integrated gene copy number, we obtained yWCBs of tunable enzyme display
levels. This tunability allowed us to avoid the crowding-limited regime
and achieve a maximum enzyme density per cell. As a result, the best
strain showed a cellulose-to-ethanol yield of 4.92 g/g, corresponding
to 96% of the theoretical maximum and near-complete conversion (∼96%)
of the starting cellulose (1% PASC). Our holistic engineering strategy
that combines a population and single-cell level approach is broadly
applicable to enhance the WCB performance in other biocatalytic cascade
schemes
Suzuki Reaction within the Core−Corona Nanoreactor of Poly(<i>N</i>-isopropylacrylamide)-Grafted Pd Nanoparticle in Water
A nanoreactor of poly(N-isopropylacrylamide)-grafted Pd nanoparticle (Pd@PNIPAM) is proposed for the Suzuki reaction performed in the sole solvent of water. The Pd@PNIPAM nanoparticle has a core of Pd nanoparticle and a corona of poly(N-isopropylacrylamide) brushes. The Pd@PNIPAM nanoparticle can act as a nanoreactor for the Suzuki reaction since the grafted poly(N-isopropylacrylamide) brushes provide a nanoenvironment for guest molecules. Both hydrophilic and hydrophobic reactants can be enriched in the nanoreactor of Pd@PNIPAM, and therefore the Suzuki reaction within the nanoreactor is performed in water at room temperature or above the phase-transition temperature of the corona-forming brushes of poly(N-isopropylacrylamide). Besides, the nanoreactor of Pd@PNIPAM can be recycled due to the reversible phase-transition of the poly(N-isopropylacrylamide) brushes
Discovery of Novel Dual Inhibitors Targeting Mutant IDH1 and NAMPT for the Treatment of Glioma with IDH1Mutation
The targeting of cancer cell intrinsic
metabolism has emerged as
a promising strategy for antitumor intervention. In the study, we
identified the first-in-class small molecules that effectively inhibit
both mutant isocitrate dehydrogenase 1 (mIDH1) and nicotinamide phosphoribosyltransferase
(NAMPT), two crucial targets in cancer metabolism, through structure-based
drug design. Notably, compound 23h exhibits excellent
and balanced inhibitory activities against both mIDH1 (IC50 = 14.93 nM) and NAMPT (IC50 = 12.56 nM), leading to significant
suppression of IDH1-mutated glioma cell (U87 MG-IDH1R132H) proliferation. Significantly, compound 23h has the
ability to cross the blood–brain barrier (B/P ratio, 0.76)
and demonstrates remarkable in vivo antitumor efficacy (20 mg/kg)
in the U87 MG-IDH1R132H orthotopic transplantation mouse
models without any notable toxicity. This proof-of-concept investigation
substantiates the viability of discovering small molecules that concurrently
target mIDH1 and NAMPT, providing valuable leads for the treatment
of glioma and an efficient approach for the discovery of multitarget
antitumor drugs
Discovery of Novel Dual Inhibitors Targeting Mutant IDH1 and NAMPT for the Treatment of Glioma with IDH1Mutation
The targeting of cancer cell intrinsic
metabolism has emerged as
a promising strategy for antitumor intervention. In the study, we
identified the first-in-class small molecules that effectively inhibit
both mutant isocitrate dehydrogenase 1 (mIDH1) and nicotinamide phosphoribosyltransferase
(NAMPT), two crucial targets in cancer metabolism, through structure-based
drug design. Notably, compound 23h exhibits excellent
and balanced inhibitory activities against both mIDH1 (IC50 = 14.93 nM) and NAMPT (IC50 = 12.56 nM), leading to significant
suppression of IDH1-mutated glioma cell (U87 MG-IDH1R132H) proliferation. Significantly, compound 23h has the
ability to cross the blood–brain barrier (B/P ratio, 0.76)
and demonstrates remarkable in vivo antitumor efficacy (20 mg/kg)
in the U87 MG-IDH1R132H orthotopic transplantation mouse
models without any notable toxicity. This proof-of-concept investigation
substantiates the viability of discovering small molecules that concurrently
target mIDH1 and NAMPT, providing valuable leads for the treatment
of glioma and an efficient approach for the discovery of multitarget
antitumor drugs
Discovery of Novel Dual Inhibitors Targeting Mutant IDH1 and NAMPT for the Treatment of Glioma with IDH1Mutation
The targeting of cancer cell intrinsic
metabolism has emerged as
a promising strategy for antitumor intervention. In the study, we
identified the first-in-class small molecules that effectively inhibit
both mutant isocitrate dehydrogenase 1 (mIDH1) and nicotinamide phosphoribosyltransferase
(NAMPT), two crucial targets in cancer metabolism, through structure-based
drug design. Notably, compound 23h exhibits excellent
and balanced inhibitory activities against both mIDH1 (IC50 = 14.93 nM) and NAMPT (IC50 = 12.56 nM), leading to significant
suppression of IDH1-mutated glioma cell (U87 MG-IDH1R132H) proliferation. Significantly, compound 23h has the
ability to cross the blood–brain barrier (B/P ratio, 0.76)
and demonstrates remarkable in vivo antitumor efficacy (20 mg/kg)
in the U87 MG-IDH1R132H orthotopic transplantation mouse
models without any notable toxicity. This proof-of-concept investigation
substantiates the viability of discovering small molecules that concurrently
target mIDH1 and NAMPT, providing valuable leads for the treatment
of glioma and an efficient approach for the discovery of multitarget
antitumor drugs
Discovery of Novel Dual Inhibitors Targeting Mutant IDH1 and NAMPT for the Treatment of Glioma with IDH1Mutation
The targeting of cancer cell intrinsic
metabolism has emerged as
a promising strategy for antitumor intervention. In the study, we
identified the first-in-class small molecules that effectively inhibit
both mutant isocitrate dehydrogenase 1 (mIDH1) and nicotinamide phosphoribosyltransferase
(NAMPT), two crucial targets in cancer metabolism, through structure-based
drug design. Notably, compound 23h exhibits excellent
and balanced inhibitory activities against both mIDH1 (IC50 = 14.93 nM) and NAMPT (IC50 = 12.56 nM), leading to significant
suppression of IDH1-mutated glioma cell (U87 MG-IDH1R132H) proliferation. Significantly, compound 23h has the
ability to cross the blood–brain barrier (B/P ratio, 0.76)
and demonstrates remarkable in vivo antitumor efficacy (20 mg/kg)
in the U87 MG-IDH1R132H orthotopic transplantation mouse
models without any notable toxicity. This proof-of-concept investigation
substantiates the viability of discovering small molecules that concurrently
target mIDH1 and NAMPT, providing valuable leads for the treatment
of glioma and an efficient approach for the discovery of multitarget
antitumor drugs
Phenylalanine Dipeptide-Regulated Ag/In<sub>2</sub>O<sub>3</sub> Nanocomposites for Enhanced NO<sub>2</sub> Gas Sensing at Room Temperature with UV Illumination
This work demonstrates that phenylalanine
dipeptide-regulated silver
can improve the gas sensing performance of a nitrogen dioxide (NO2) gas sensor. Herein, Ag/In2O3 was prepared
by a hydrothermal method to detect NO2 gas, where varying
amounts of phenylalanine dipeptide (FF) were introduced to regulate
the growth of Ag NPs. The morphologies, microstructures, and compositions
of the obtained samples were characterized in detail, and the results
indicate that Ag NPs grow into nanorods with the regulation of FF.
The gas sensing characteristics were systematically investigated with
UV illumination (365 nm) at room temperature (25 °C). Upon exposure
to NO2 gas, the optimal sensor exhibits a relatively high
response value, good linearity, and satisfactory stability. In addition,
the sensor can maintain good gas sensing performance under varying
humidity. The reason underlying the observed enhancement in the gas
sensing property is the formation of more active sites with the Ag
nanorod structure. This study suggests that the introduction of polypeptides
is a promising idea to improve the performance of gas sensors
Discovery of Novel Dual Inhibitors Targeting Mutant IDH1 and NAMPT for the Treatment of Glioma with IDH1Mutation
The targeting of cancer cell intrinsic
metabolism has emerged as
a promising strategy for antitumor intervention. In the study, we
identified the first-in-class small molecules that effectively inhibit
both mutant isocitrate dehydrogenase 1 (mIDH1) and nicotinamide phosphoribosyltransferase
(NAMPT), two crucial targets in cancer metabolism, through structure-based
drug design. Notably, compound 23h exhibits excellent
and balanced inhibitory activities against both mIDH1 (IC50 = 14.93 nM) and NAMPT (IC50 = 12.56 nM), leading to significant
suppression of IDH1-mutated glioma cell (U87 MG-IDH1R132H) proliferation. Significantly, compound 23h has the
ability to cross the blood–brain barrier (B/P ratio, 0.76)
and demonstrates remarkable in vivo antitumor efficacy (20 mg/kg)
in the U87 MG-IDH1R132H orthotopic transplantation mouse
models without any notable toxicity. This proof-of-concept investigation
substantiates the viability of discovering small molecules that concurrently
target mIDH1 and NAMPT, providing valuable leads for the treatment
of glioma and an efficient approach for the discovery of multitarget
antitumor drugs
