Combined cross-linked enzyme aggregates (combi-CLEAs) represent a promising carrier-free immobilized enzyme technology. This study describes the preparation of combi-CLEAs comprising leucine dehydrogenase (LeuDH) and formate dehydrogenase (FDH) for the regeneration of cofactor nicotinamide adenine dinucleotide necessary for 2-aminobutyric acid production. Different from traditional methods using ammonium sulfate or organic reagents as precipitant, this work utilized low concentrations of calcium ions to purify and precipitate the histidine-tagged enzymes.
View Article and Find Full Text PDFMetal-organic frameworks constructed from Zr usually possess excellent chemical and physical stability. Therefore, they have become attractive platforms in various fields. In this work, two families of hybrid materials based on ZrSQU have been designed and synthesized, named Im@ZrSQU and Cu@ZrSQU, respectively.
View Article and Find Full Text PDFEthnopharmacological Relevance: Danggui Buxue decoction (DBD) is a classic herbal decoction consisting of Astragali Radix (AR) and Angelica Sinensis Radix (ASR) with a 5:1 wt ratio, which can supplement 'blood' and 'qi' (vital energy) for the treatment of clinical diseases. According to Traditional Chinese Medicine (TCM) theory, dementia is induced by Blood deficiency and Qi weakness, which causes a decline in cognition. However, the underlying mechanisms of DBD improving cognition deficits in neurodegenerative disease are no clear.
View Article and Find Full Text PDFThe anhydrous proton conductivity of Im@IEF-11 resulting from the integration of imidazole and porous IEF-11 has been investigated, and the highest proton conductive value can reach up to 7.64 × 10 S cm. Furthermore, IEF-11 is also developed to reduce CO due to its reasonable structure and suitable energy band, and its CO formation rate is 31.
View Article and Find Full Text PDFThe practical application of lithium-sulfur (Li-S) batteries is greatly hindered by the shuttle effect of dissolved polysulfides in the sulfur cathode and the severe dendritic growth in the lithium anode. Adopting one type of effective host with dual-functions including both inhibiting polysulfide dissolution and regulating Li plating/stripping, is recently an emerging research highlight in Li-S battery. This review focuses on such dual-functional hosts and systematically summarizes the recent research progress and application scenarios.
View Article and Find Full Text PDFThe photoreduction deposition method is employed to fabricate a family of silver nanoparticle (Ag NP)-modified polyoxometalate-based metal-organic framework () photocatalysts, named . The title photocatalysts, , can be used for the photocatalytic reduction of CO and are observed to efficiently reduce CO into CO, in which the highest reduction rate is 22.28 μmol g h, 3 times greater than that of .
View Article and Find Full Text PDFBackground: In recent years, a growing body of research has revealed that long noncoding RNAs (lncRNAs) participate in regulating genomic instability.
Materials And Methods: We obtained RNA expression profiles, somatic mutation profiles, clinical information, and pathological features of colorectal cancer (CRC) from The Cancer Genome Atlas project. We divided the cohort into two groups based on mutation frequency and identified genomic instability-related lncRNAs (GI-lncRNAs) using R software.
Appl Biochem Biotechnol
August 2022
In this study, nitrilase (Nit) was immobilized in zeolite imidazole framework-90 (ZIF-90) by one-pot biomimetic mineralization strategy. The structure, morphology and functional groups of ZIF-90 and immobilized enzyme Nit@ZIF-90 were characterized by scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). Circular dichroism (CD) proved that the immobilized method of encapsulation in ZIF-90 could effectively maintain the intrinsic conformation of Nit.
View Article and Find Full Text PDFTo study the effect of SpyTag/SpyCatcher cyclization on stability and refolding of protein, we constructed a cyclized green fluorescent protein (SRGFP) and its derivative to act as a linear structure control (L-SRGFP). SRGFP and L-SRGFP showed similar fluorescence characteristics to the wild-type GFP, while compared with GFP and L-SRGFP, the thermal stability and denaturation resistance of SRGFP were improved. The refolding efficiencies of these three denatured proteins were investigated under different pH, temperature and initial protein concentration conditions, and it was found that SRGFP was superior to GFP and L-SRGFP in terms of refolding yield and refolding speed.
View Article and Find Full Text PDFMetal-organic frameworks (MOFs) provide an ideal platform for loading various guests owing to their available space, and can be developed as a class of multifunctional materials. Herein, we cover the design and synthesis of two kinds of exchanged frameworks with multifunctional applications based on HImDC and In(NO)·2HO through guest exchange inside the framework. The guest ammonium ion (NH) and [Ru(2,2'-bipyridine)] (Rubpy) are selected to exchange the dimethylammonium cation (MeNH) encapsulated within , giving birth to two kinds of new MOFs, named and respectively.
View Article and Find Full Text PDFSleep disturbance is common in patients with Alzheimer's disease (AD), and orexin A is a pivotal neurotransmitter for bidirectionally regulating the amyloid-β (Aβ) deposition of AD brain and poor sleep. In the present study, we examined the characteristic of sleep-wake architecture in APPswe/PSldE9 (APP/PS1) and Aβ-treated mice using electroencephalogram (EEG) and electromyographic (EMG) analysis. We compared the expression of orexin A, distribution, and morphology of the corresponding orexin A-positive neurons using innovative methods including three-dimensional reconstruction and brain tissue clearing between wild type (WT) and APP/PS1 mice.
View Article and Find Full Text PDFInt J Biol Macromol
February 2022
It is a promising strategy to prepare composite photocatalysts based on MOFs and semiconductors for enhancing photocatalytic reduction of carbon dioxide (CO). A family of binary composite photocatalysts () with different CdS contents have been designed and synthesized, which have been explored for photocatalytic reduction of CO. can efficiently convert CO into CO under visible light irradiation the solid-gas mode in the absence of sacrificial agents and photosensitizers.
View Article and Find Full Text PDFBased on the specific and spontaneous formation of isopeptide bonds by SpyCatcher/SpyTag, we have developed a one-step method for purification and immobilization of recombinant proteins. The procedure is to immobilize SpyCatcher on glyoxyl agarose gels, and then the SpyCatcher immobilisate can be used to immobilize the SpyTag-fused protein in the crude extract selectively. A mutant of SpyCatcher (mSC), in which a peptide (LysGlyLysGlyLysGly) was added to the C-terminus of SpyCatcher and three lysine residues around the SpyTag/SpyCatcher binding domain were replaced with arginine, was designed to improve the attachment of SpyCatcher to the support.
View Article and Find Full Text PDFPhotoreduction of carbon dioxide (CO) provides an effective perspective for solving the energy crisis and environmental problems. Herein, two types of composite photocatalysts (TiO/ZIF-8) based on ZIF-8 and TiO have been designed and synthesized with the help of the grinding method and the solid-synthesis method. Both composite photocatalysts are employed for the photocatalytic reduction of CO.
View Article and Find Full Text PDFCephalosporin C acylase (CCA) is capable of catalyzing cephalosporin C (CPC) to produce 7-aminocephalosporanic acid (7-ACA), an intermediate of semi-synthetic cephalosporins. Inducible expression is usually used for CCA. To improve the efficiency of CCA expression without gene induction, three recombinant strains regulated by constitutive promoters BBa_J23105, PLtetO1, and tac were constructed, respectively.
View Article and Find Full Text PDFSophoricoside (SOP), an isoflavone glycoside isolated from seed of Sophora japonica L., has been reported to have various pharmacological activities, including anti-cancer, anti-allergy and anti-inflammation. However, the effect of SOP on lipopolysaccharides (LPS)-acute lung injury (ALI) is completely unclear.
View Article and Find Full Text PDFDuring enzyme immobilization, enzyme activity and protein distribution are affected by various factors such as enzyme load, temperature, and pH. In general, two types of protein distribution patterns (heterogeneous or homogeneous) are observed inside a porous carrier, owing to differences in preparation parameters. During the immobilization of a fusion protein (CCApH) of cephalosporin C acylase (CCA) and pHluorin (a pH-sensitive mutant of green fluorescent protein), different shaking speeds induced obvious differences in protein distribution on an epoxy carrier, LX-1000EPC.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2020
Cephalosporin C acylase (CCA) is the key enzyme in the production of 7-aminocephalosporanic acid (7-ACA) via a one-step enzymatic process. To improve the soluble expression level of CCA in recombinant Escherichia coli at elevated temperatures, a library of T7 promoter mutants was created by site-saturation mutagenesis, and a series of mutated promoters were subsequently screened. Green fluorescent protein (GFP) was fused to the C-terminus of CCA to facilitate library screening, and the expression of the CCA and GFP fusion proteins was investigated under the control of the T7 promoter.
View Article and Find Full Text PDFObjectives: To improve the thermostability and organic solvent tolerance of L-phenylserine aldolase, the in vivo SpyTag/SpyCatcher cyclization strategy was applied in this work.
Results: The in vivo cyclization of L-phenylserine aldolase was achieved by fusing the tags of SpyCatcher and SpyTag to the N- and C-termini of the enzyme, respectively. The k values and the circular dichroism spectra of the linear and cyclized LPAs are very similar, indicating that the cyclized LPA can be folded appropriately like the wild type.