Key Laboratory of Molecular Biophysics

Wuhan, China

Key Laboratory of Molecular Biophysics

Wuhan, China

Time filter

Source Type

Xiang M.,Huazhong University of Science and Technology | Xiang M.,Key Laboratory of Molecular Biophysics | Xiang M.,South-Central University for Nationalities | Su H.,Renmin University of China | And 4 more authors.
Journal of Medicinal Plants Research | Year: 2011

Polygonum amplexicaule D. Don (Polygonaceae) (Chinese name: Xuesanqi) is a widely distributed medicinal plant in China. It has been used in folk medicine to treat many common and frequentlyoccurring diseases, such as cardiovascular and cerebrovascular diseases, fractures, pain, etc. Thus, this plant has been of interest to researchers. However, the chemical constituents of Xuesanqi have not been investigated systematically. This study isolated and identified some effective compounds in this plant. The structure of important active chemicals of Xuesanqi from different regions was determined for the first time. Twelve phenolic compounds were isolated from this plant. Vanillin, isovanillic acid, phydroxyphenethyl alcohol, dihydro-kaempferol, and 5,7-dihydroxychromone were determined for the first time from Polygonum. As markers for quality standard of this herb, the content of methyl caffeate and ethyl caffeate was determined by HPLC. It was found that Xuesanqi from Wufeng, Lichuan, Badong Counties in Hubei Province and Jiujiang City of Jiangxi Province had higher content of both chemicals. The results suggest that the herb might be a potential source of phenolic compounds of an agent for improving blood circulation, treating various fractures, muscle and tissue swelling, and pain. © 2011 Academic Journals.


Zhao C.F.,Huazhong University of Science and Technology | Zhao C.F.,Key Laboratory of Molecular Biophysics | Li S.,Huazhong University of Science and Technology | Li S.J.,Huazhong University of Science and Technology | And 4 more authors.
Journal of Functional Foods | Year: 2013

Optimized solid-liquid extraction conditions by response surface methodology (RSM) and optimal solvent selectivity liquid-liquid fractionation by mixture design were studied for process of Pyracantha fortuneana fruits (PFF) healthy products. A combination of total polyphenolic content (TPC), total antioxidant activity (TAA) and chromatographic profiling was used to evaluate the optimization. RSM results were ethanol concentration, 71%; extraction temperature, 51. °C; and pH solution, 3.2. The mixture design indicated that the fraction with the highest TAA and TPC was directed to ethyl-acetate phase. The fractions of water-soluble and n-butylalcohol-soluble were rich in TAA and TPC compared with the starting row of PFF. Twenty-seven polyphenols were detected in chromatographic profilings, most of which were reported for the first time in this study. The improvements of accessibility in the optimized fractions suggest their flexible applicabilities for nutraceutical food industries. This study may be crucial approach for all similar natural functional product optimization. © 2013 Elsevier Ltd.


Li W.,Huazhong University of Science and Technology | Li W.,Key Laboratory of Molecular Biophysics | Chen W.-S.,Huazhong University of Science and Technology | Zhou P.-P.,Huazhong University of Science and Technology | And 4 more authors.
Chemical Engineering Journal | Year: 2013

Biogenic precipitation of calcium carbonate (CaCO3) has attracted much attention due to its role in many geological processes, applications of Geological and Civil Engineering as well as environmental treatments. The present paper focused on the biocatalytic precipitation of CaCO3 by the extracellular carbonic anhydrase (CA) extracted and partially purified from the culture of Bacillus cereus. The kinetics of CaCO3 precipitation catalyzed by the bacterial CA at different initial concentrations of Ca2+ (C0(Ca2+)) was investigated through the gaseous diffusion system. The polymorph and morphology of CaCO3 crystals obtained in the precipitation process were also analyzed using XRD, FTIR and FESEM. The results showed that in the process of CaCO3 precipitation catalyzed by bacterial CA, the change in the amount of deposited Ca2+ at different C0(Ca2+) fitted well with the exponential model. Greater fluctuation of pH occurred in the water control group during the rising process of pH, while in the CA group the pH increased more steadily. This may be related to the role of CA in pH regulation. The precipitation rate of CaCO3 increased with the increasing C0(Ca2+), but overhigh C0(Ca2+) of 100mmol/L had a certain negative influence on CaCO3 precipitation catalyzed by bacterial CA. The integrated results of XRD, FTIR and FESEM analysis showed that the C0(Ca2+) had greater effect on the polymorph and morphology of CaCO3 crystals formed in the presence of bacterial CA. The lower C0(Ca2+) favored the formation of vaterite and the higher C0(Ca2+) favored the formation of calcite. © 2012 Elsevier B.V.


Chen T.,Key Laboratory of Molecular Biophysics | Yang W.,Key Laboratory of Molecular Biophysics | Guo Y.,Key Laboratory of Molecular Biophysics | Yuan R.,Key Laboratory of Molecular Biophysics | And 2 more authors.
Enzyme and Microbial Technology | Year: 2014

A novel magnetic Fe3O4 nanoparticles (MNPs) coupled with agarose (AMNPs) was synthesized using co-precipitation via alkaline condition and span-80 surfactants in organic solvent. Iminodiacetate was first attached to the MNPs through epichlorohydrin agent and then chelated with metal ions. The morphology and chemical properties of these prepared supports were characterized by scanning electron microscopy (SEM), X-ray power diffraction (XRD), vibrating sample magnetometer (VSM), and Fourier transform infrared spectroscopy (FT-IR). Among them, the Co2+-chelated AMNPs (AMNPs-ECH-IDA-Co2+) showed the second highest enzyme adsorption capacity of 1.81mg/g particles, and achieved the largest activity recovery of 117% per protein gram in immobilization of β-glucosidase (BGL). The Michaelis constant (Km) and Vmax of the immobilized BGL were 0.904mM and 0.057μmol/min, respectively, and its activation energy was much lower than the free form. Moreover, the immobilized enzyme exhibited enhanced thermostability and operational stability. It still retained more than 90% of its initial activity after being operated for 15 successive batches. This study demonstrates that the immobilized β-glucosidase has a good prospect in industrial applications. © 2014 Elsevier Inc.


Wang H.-B.,Huazhong University of Science and Technology | Wang H.-B.,Key Laboratory of Molecular Biophysics | Luo J.,Huazhong University of Science and Technology | Luo J.,Key Laboratory of Molecular Biophysics | And 6 more authors.
Journal of Industrial Microbiology and Biotechnology | Year: 2014

The cellular response of Blakeslea trispora to oxidative stress induced by H2O2 in shake flask culture was investigated in this study. A mild oxidative stress was created by adding 40 μm of H 2O2 into the medium after 3 days of the fermentation. The production of β-carotene increased nearly 38 % after a 6-day culture. Under the oxidative stress induced by H2O2, the expressions of hmgr, ipi, carG, carRA, and carB involving the β-carotene biosynthetic pathway all increased in 3 h. The aerobic metabolism of glucose remarkably accelerated within 24 h. In addition, the specific activities of superoxide dismutase and catalase were significantly increased. These changes of B. trispora were responses for reducing cell injury, and the reasons for increasing β-carotene production caused by H2O2. © 2013 Society for Industrial Microbiology and Biotechnology.


Song W.,Huazhong University of Science and Technology | Song W.,Key Laboratory of Molecular Biophysics | Ao M.Z.,Huazhong University of Science and Technology | Ao M.Z.,Key Laboratory of Molecular Biophysics | And 8 more authors.
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2012

In this paper, the interaction of human serum albumin (HSA) with phillygenin was investigated by fluorescence, circular dichroism (CD), UV-vis spectroscopic and molecular docking methods under physiological conditions. The Stern-Volmer analysis indicated that the fluorescence quenching of HSA by phillygenin resulted from static mechanism, and the binding constants were 1.71 × 10 5, 1.61 × 10 5 and 1.47 × 10 4 at 300, 305 and 310 K, respectively. The results of UV-vis spectra show that the secondary structure of the protein has been changed in the presence of phillygenin. The CD spectra showed that HSA conformation was altered by phillygenin with a major reduction of α-helix and an increase in β-sheet and random coil structures, indicating a partial protein unfolding. The distance between donor (HSA) and acceptor (phillygenin) was calculated to be 3.52 nm and the results of synchronous fluorescence spectra showed that binding of phillygenin to HSA can induce conformational changes in HSA. Molecular docking experiments found that phillygenin binds with HSA at IIIA domain of hydrophobic pocket with hydrogen bond interactions. The ionic bonds were formed with the O (4), O (5) and O (6) of phillygenin with nitrogen of ASN109, ARG186 and LEU115, respectively. The hydrogen bonds are formed between O (2) of phillygenin and SER419. In the presence of copper (II), iron (III) and alcohol, the apparent association constant K A and the number of binding sites of phillygenin on HSA were both decreased in the range of 88.84-91.97% and 16.09-18.85%, respectively. In view of the evidence presented, it is expected to enrich our knowledge of the interaction dynamics of phillygenin to the important plasma protein HSA, and it is also expected to provide important information of designs of new inspired drugs. © 2011 Elsevier B.V. All rights reserved.


Zhang H.,Key Laboratory of Molecular Biophysics | Zhang H.,Huazhong University of Science and Technology | Chen J.,Key Laboratory of Molecular Biophysics | Chen J.,Huazhong University of Science and Technology | And 6 more authors.
FEBS Letters | Year: 2013

Himastatin is a novel antibiotic featuring a bicyclohexadepsipeptide structure. On the himastatin biosynthesis pathway, three cytochrome P450s (HmtT, HmtN, HmtS) are responsible for the post-tailoring of the cyclohexadepsipeptide backbone. Here we report the crystal structures of HmtT and HmtN. The overall structures of these two proteins are homologous to other cytochrome P450s. However, the exceptionally long F-G loop in HmtT has a highly unusual conformation and extends deep into the active site. As a result, the F/G helices of HmtT are both kinked. In contrast, the F/G helices of HmtN are straight. Also, the F/G helices in HmtT and HmtN take distinctive orientations, which may be a contributing factor for the substrate specificity of these two enzymes. © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.


Li W.,Huazhong University of Science and Technology | Li W.,Key Laboratory of Molecular Biophysics | Chen W.-S.,Huazhong University of Science and Technology | Zhou P.-P.,Huazhong University of Science and Technology | And 4 more authors.
Colloids and Surfaces B: Biointerfaces | Year: 2013

The dynamics of calcium carbonate (CaCO3) precipitation induced by microbial intracellular or extracellular carbonic anhydrase (CA) at initial pH 6.0, 6.5, 7.0 and 8.0 were investigated through the gaseous diffusion method. The results indicated that both the intracellular and extracellular CA could promote CaCO3 precipitation. The Ca2+ ions in the enzymatic systems at initial pH 8.0 were completely deposited at 48h, which were respectively 21h, 15h and 14h earlier compared with that at initial pH 6.0, pH 6.5 and pH 7.0, indicating that higher pH favored CaCO3 precipitation in the experimental pH range, and was beneficial to the catalytic action of microbial CA on CaCO3 precipitation. In addition, XRD analysis indicated that the CaCO3 precipitates were mainly calcite crystals in the presence of microbial CA. With increasing deposition time, the crystals gradually changed from prism shape to pyramid-like or irregular polyhedral shape based on FESEM analysis. © 2012 Elsevier B.V.


PubMed | Yanshan University, Key laboratory of Molecular Biophysics and Key Laboratory of Neural and Vascular Biology
Type: Journal Article | Journal: Journal of computer-aided molecular design | Year: 2016

Calcium-activated chloride channels (CaCCs) play vital roles in a variety of physiological processes. Transmembrane protein 16A (TMEM16A) has been confirmed as the molecular counterpart of CaCCs which greatly pushes the molecular insights of CaCCs forward. However, the detailed mechanism of Ca(2+) binding and activating the channel is still obscure. Here, we utilized a combination of computational and electrophysiological approaches to discern the molecular mechanism by which Ca(2+) regulates the gating of TMEM16A channels. The simulation results show that the first intracellular loop serves as a Ca(2+) binding site including D439, E444 and E447. The experimental results indicate that a novel residue, E447, plays key role in Ca(2+) binding. Compared with WT TMEM16A, E447Y produces a 30-fold increase in EC50 of Ca(2+) activation and leads to a 100-fold increase in Ca(2+) concentrations that is needed to fully activate the channel. The following steered molecular dynamic (SMD) simulation data suggests that the mutations at 447 reduce the Ca(2+) dissociation energy. Our results indicated that both the electrical property and the size of the side-chain at residue 447 have significant effects on Ca(2+) dependent gating of TMEM16A.


PubMed | Key Laboratory of Molecular Biophysics
Type: Journal Article | Journal: FEBS letters | Year: 2013

Himastatin is a novel antibiotic featuring a bicyclohexadepsipeptide structure. On the himastatin biosynthesis pathway, three cytochrome P450s (HmtT, HmtN, HmtS) are responsible for the post-tailoring of the cyclohexadepsipeptide backbone. Here we report the crystal structures of HmtT and HmtN. The overall structures of these two proteins are homologous to other cytochrome P450s. However, the exceptionally long F-G loop in HmtT has a highly unusual conformation and extends deep into the active site. As a result, the F/G helices of HmtT are both kinked. In contrast, the F/G helices of HmtN are straight. Also, the F/G helices in HmtT and HmtN take distinctive orientations, which may be a contributing factor for the substrate specificity of these two enzymes.

Loading Key Laboratory of Molecular Biophysics collaborators
Loading Key Laboratory of Molecular Biophysics collaborators