749 research outputs found
Role of the Flavan-3-ol and Galloyl Moieties in the Interaction of (−)-Epigallocatechin Gallate with Serum Albumin
The principal green tea polyphenol,
(−)-epigallocatechin-3-<i>O</i>-gallate (EGCg), may
provide chemoprotection against conditions
ranging from cardiovascular disease to cancer. Binding to plasma proteins
stabilizes EGCg during its transport to targeted tissues. This study
explored the details EGCg binding to bovine serum albumin. Both fluorescence
lifetime and intensity data showed that the hydrophobic pocket between
subdomains IIA and IIIA is the binding site for EGCg. Fluorescence
and circular dichroism were used to establish the roles of the flavan-3-ol
and galloyl moieties of the EGCg in binding and to demonstrate a binding-dependent
conformational change in the protein. Competitive binding experiments
confirmed the location of binding, and molecular modeling identified
protein residues that play key roles in the interaction. This model
of EGCg–BSA interactions improves the understanding of the
likely physiological fate of this green tea-derived bioactive polyphenol
Solution-Phase Electronegativity Scale: Insight into the Chemical Behaviors of Metal Ions in Solution
By incorporating the solvent effect into the Born effective
radius,
we have proposed an electronegativity scale of metal ions in aqueous
solution with the most common oxidation states and hydration coordination
numbers in terms of the effective ionic electrostatic potential. It
is found that the metal ions in aqueous solution are poorer electron
acceptors compared to those in the gas phase. This solution-phase
electronegativity scale shows its efficiency in predicting some important
properties of metal ions in aqueous solution such as the aqueous acidities
of the metal ions, the stability constants of metal complexes, and
the solubility product constants of the metal hydroxides. We have
elaborated that the standard reduction potential and the solution-phase
electronegativity are two different quantities for describing the
processes of metal ions in aqueous solution to soak up electrons with
different final states. This work provides a new insight into the
chemical behaviors of the metal ions in aqueous solution, indicating
a potential application of this electronegativity scale to the design
of solution reactions
Phosphorus activators contribute to legacy phosphorus availability in agricultural soils: A review.
Phosphorus (P) is one of the most limiting macronutrients for crop productivity and P deficiency is a common phenomenon in agricultural soils worldwide. Despite long-term application of phosphate fertilizers to increase crop yields, P availability is often low, due to the high affinity of phosphate for the soil solid phase. It has been suggested that the accumulated (surplus) P in agricultural soils is sufficient to sustain crop yields worldwide for about 100years. In this paper, we try to clear up the potential for making use of legacy P in soils for crop growth potentially alleviating the global P resource shortage. Specifically, we try to clear up the potential of soil "P activators" for releasing fixed P. P activators accelerate and strengthen process which transform P into bio-available forms via a range of chemical reactions and biological interactions. They include phosphate solubilizing microorganisms, phosphatase enzymes and enzyme activators, low molecular weight organic acids, humic acids, lignin, crop residues, biochar and zeolites. Although reported performance is variable, there is growing evidence that P activators can promote the release of phosphate from soil and, hence, have potential for mitigating the impending global P crisis. Further basic and applied research is required to better understand the mechanisms of interaction of P activators with natural soils and to maximize activator efficacy
Additional file 1: of Effect of CYP3 A4, CYP3 A5 and ABCB1 gene polymorphisms on the clinical efficacy of tacrolimus in the treatment of nephrotic syndrome
CYP3 A4*1G gene sequencing map (forward sequencing). A: CYP3 A4 *1/*1 (wild type); B: CYP3 A4 *1/*1G (heterozygous type); C: CYP3 A4 *1G/*1G (mutant type). (TIFF 916 kb
Additional file 4: of Effect of CYP3 A4, CYP3 A5 and ABCB1 gene polymorphisms on the clinical efficacy of tacrolimus in the treatment of nephrotic syndrome
ABCB1 G2677T/A gene sequencing map (reverse sequencing). A: ABCB1 2677CC (wild type); B: ABCB1 2677CT (heterozygous type); C: ABCB1 2677CA (heterozygous type); D: ABCB1 2677TT (mutant type); E: ABCB1 2677AT (mutant type); F: ABCB1 2677AA (mutant type). (TIFF 1876 kb
Additional file 3: of Effect of CYP3 A4, CYP3 A5 and ABCB1 gene polymorphisms on the clinical efficacy of tacrolimus in the treatment of nephrotic syndrome
ABCB1 C1236T gene sequencing map (reverse sequencing). A: ABCB1 1236 GG (wild type); B: ABCB1 1236 AG (heterozygous type); C: ABCB1 1236 AA (mutant type). (TIFF 833 kb
Constructing Optimal Coarse-Grained Sites of Huge Biomolecules by Fluctuation Maximization
Coarse-grained
(CG) models are valuable tools for the study of
functions of large biomolecules on large length and time scales. The
definition of CG representations for huge biomolecules is always a
formidable challenge. In this work, we propose a new method called
fluctuation maximization coarse-graining (FM-CG) to construct the
CG sites of biomolecules. The defined residual in FM-CG converges
to a maximal value as the number of CG sites increases, allowing an
optimal CG model to be rigorously defined on the basis of the maximum.
More importantly, we developed a robust algorithm called stepwise
local iterative optimization (SLIO) to accelerate the process of coarse-graining
large biomolecules. By means of the efficient SLIO algorithm, the
computational cost of coarse-graining large biomolecules is reduced
to within the time scale of seconds, which is far lower than that
of conventional simulated annealing. The coarse-graining of two huge
systems, chaperonin GroEL and lengsin, indicates that our new methods
can coarse-grain huge biomolecular systems with up to 10 000
residues within the time scale of minutes. The further parametrization
of CG sites derived from FM-CG allows us to construct the corresponding
CG models for studies of the functions of huge biomolecular systems
Goodness-of-fit for the CD-RISC with different models.
<p>Goodness-of-fit for the CD-RISC with different models.</p
Ordinal reliability coefficients, correlation coefficients and concurrent validity evidence on the CD-RISC with Chinese military sample.
<p>Ordinal reliability coefficients, correlation coefficients and concurrent validity evidence on the CD-RISC with Chinese military sample.</p
The eigenvalues and factor pattern of the CD-RISC with Chinese military sample.
<p>The eigenvalues and factor pattern of the CD-RISC with Chinese military sample.</p
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