The circular dichroism spectroscopic analysis of the Blodgett-deposited films suggests the protein to be in largely α-helical conformation. The linear dichroism investigations suggest the protein to be anisotropically deposited. Blodgett deposition of the Langmuir films, therefore, is a rather simple method for preparing oriented monolayers of surface-active macromolecules.The development and utilization of inorganic material biosynthesis have evolved into single macromolecular systems. A putative cystathionine γ-lyase of bacteria Stenotrophomonas maltophilia (smCSE) is a newly identified biomolecule that enables the synthesis of nanomaterials. Due to the lack of structural information, the mechanism of smCSE biosynthesis remains unclear. Herein, we obtain two atomic-resolution smCSE-form X-ray structures and confirm that the conformational changes of Tyr108 and Lys206 within the enzyme active sites are critical for the protein-driven synthesis of metal sulfide quantum dots (QDs). The structural stability of tetramer and the specificity of surface amino acids are the basis for smCSE to synthesize quantum dots. The size of QD products can be regulated by predesigned amino acids and the morphology can be controlled through proteolytic treatments. The growth rate is enhanced by the stabilization of a flexible loop in the active site, as shown by the X-ray structure of the engineered protein which fused with a dodecapeptide. We further prove that the smCSE-driven route can be applied to the general synthesis of other metal sulfide nanoparticles. These results provide a better understanding of the mechanism of QD biosynthesis and a new perspective on the control of this biosynthesis by protein modification.In this study, encoding sequence of a new type 2 RIP (pebulin) was isolated and cloned from dwarf elder (Sambucus ebulus L.) native to the northern regions of Iran. The nucleotide sequence of pebulin was ligated to the pET-28a(+) expression plasmid and cloned into the E. coli strain BL21 (DE3) in order to express heterologously of recombinant protein. The recombinant pebulin protein was mainly produced in the form of insoluble inclusion bodies probably because to absence of N-glycosylation process in E. coli. Therefore, in order to increase the expression of recombinant protein in soluble form, co-expression of the target protein with the pG-Tf2 chaperone plasmid and incubation of bacterial culture under low temperature were used to enhance solubility and accumulation of recombinant protein. After purification of the recombinant protein using affinity chromatography method, the bioactivity of pebulin was analyzed by hemagglutination, anticancer, and antifungal assays. The results of the hemagglutination assay showed that purified pebulin agglutinated erythrocytes in all human blood groups. In addition, pebulin considerably inhibited the proliferation of cancer cell lines MCF-7 and HT-29 in a time- and dose-dependent manner and indicated remarkably growth-inhibiting effect against the plant pathogenic fungi such as Alternaria solani and Fusarium oxysporum.Alzheimer's disease (AD) is an obstinate and progressive neurodegenerative disorder, mainly characterized by cognitive decline. Increasing number of AD patients and the lack of promising treatment strategies demands novel therapeutic agents to combat various disease pathologies in AD. Recent progresses in understanding molecular mechanisms in AD helped researchers to streamline the various therapeutic approaches. this website Inhibiting acetylcholinesterase (AChE) activity has emerged as one of the potential treatment strategies. The present study discusses the identification of two potent AChE inhibitors (ZINC11709541 and ZINC11996936) from ZINC database through conventional in silico approaches and their in vitro validations. These inhibitors have strong preferences towards AChE than butyrylcholinesterase (BChE) and didn't evoke any significant reduction in the cell viability of HEK-293 cells and primary cortical neurons. Furthermore, promising neuroprotective properties has also been displayed against glutamate induced excitotoxicity in primary cortical neurons. The present study proposes two potential drug lead compounds for the treatment of AD, that can be used for further studies and preclinical evaluation.In order to solve the antibiotic resistance, the research on antibiotic substitutes has received an extensive attention. Many studies have shown that β-glucan and mannan from yeast cell wall have the potential to replace antibiotics for the prevention and treatment of animal diseases, thereby reducing the development and spread of antibiotic-resistant bacterial pathogens. β-Glucan and mannan had a variety of biological functions, including improving the intestinal environment, stimulating innate and acquired immunity, adsorbing mycotoxins, enhancing antioxidant capacity, and so on. The biological activities of β-glucan and mannan can be improved by chemically modifying its primary structure or reducing molecular weight. In this paper, the structure, preparation, modification, and biological activities of β-glucan and mannan were reviewed, which provided future perspectives of β-glucan and mannan.
This study examined the patterned treatment of corneal collagen cross-linking (CXL) for keratoconus to reduce the complications caused by ultraviolet (UV) irradiation. By modifying the method of UV irradiation during the cross-linking process, cross-linking with a special structure is achieved, and the cross-linking effect is analyzed and compared to that of traditional cross-linking. By constructing an animal model of keratoconus, the process and effect of corneal cross-linking can be investigated more fundamentally. These studies provide valuable references for future cross-linking precision improvement and specialization.
By injecting exogenous collagenase into the corneal stroma of rabbits, the balance between collagenase and collagenase inhibitor in the corneal stroma was disrupted, the collagen fiber structure of the cornea was broken to simulate the pathogenesis of keratoconus, and an animal model of keratoconus was thus constructed. Two custom cross-linking patterns were designed with reference to the cable dome structure, and these two special patterns were irradiated and cross-linked by a DMD chip.this website
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