1,720,978 research outputs found
Phosphate Binding Protein이 세포질에 발현된 재조합 박테리아를 이용한 인 제거
No full textIn the present work, we constructed a recombinant Escherichia coli with cytoplasmic-expressed phosphate-binding protein (PBP) and investigated its phosphate removal in water phase. When the recombinant bacteria were cultured for 6 h to treat phosphate, the removal efficiencies were 90, 49, and 41% for the treatment of 1.0, 1.5, and 2.0 mg/L phosphate, respectively, indicating good specific phosphate removal of our developed system. Also, cell densities of 2.5 and 5.0 Optical density resulted in high phosphate removal efficiencies and ~80% of 2.0 mg/L phosphate was efficiently removed. A novel biotechnology developed in this study could be effectively employed for resolving eutrophication problem in water body.ungraded11Nscopuskc
Fast and facile biodegradation of polystyrene by the gut microbial flora of Plesiophthalmus davidis larvae
No full textPolystyrene (PS), which accounts for a significant fraction of plastic wastes, is difficult to biodegrade due to its unique molecular structure. Therefore, biodegradation and chemical modification of PS are limited. In this study, we report PS biodegradation by the larvae of the darkling beetle Plesiophthalmus davidis (Coleoptera: Tenebrionidae). In 14 days, P. davidis ingested 34.27��4.04 mg of Styrofoam (PS foam) per larva and survived by feeding only on Styrofoam. Fourier transform infrared spectroscopy confirmed that the ingested Styrofoam was oxidized. Gel permeation chromatography analysis indicated the decrease in average molecular weight of the residual PS in the frass compared with the feed Styrofoam. When the extracted gut flora was cultured for 20 days with PS films, biofilm and cavities were observed by scanning electron microscopy and atomic force microscopy. X-ray photoelectron spectroscopy (XPS) studies revealed that C-O bonding was introduced into the biodegraded PS film. Serratia sp. strain WSW (KCTC 82146), which was isolated from the gut flora, also formed a biofilm and cavities on the PS film in 20 days, but its degradation was less prominent than the gut flora. XPS confirmed that C-O and C=O bonds were introduced into the biodegraded PS film by Serratia sp. WSW. Microbial community analysis revealed that Serratia was in the gut flora in significant amounts and increased sixfold when the larvae were fed Styrofoam for 2 weeks. This suggests that P. davidis larvae and its gut bacteria could be used to chemically modify and rapidly degrade PS. ? 2020 American Society for Microbiology.11Nsciescopu
Electrohydrodynamic Sprayable Amphiphilic Polysaccharide-Clasped Nanoscale Self-Assembly for In Vivo Imaging
No full textThe work presented in this report demonstrates that amphiphilic polysaccharide-clasped self-assembly (Amp-SA) with nanometer size, encapsulating hydrophobic nanoparticles (NPs) can be generated via electrohydrodynamic spraying. It is observed that the formation of hydrophobic NP-encapsulated Amp-SA is dependent on the surface chemistry of NPs. The citrate-coated magnetic NPs (MNPs-Cit) were also prepared and compared. The hydrophobic magnetic NP-encapsulated Amp-SA (Amp-SA-M) exhibited around 2.7-2.8-fold higher values in r2 relaxivity than that of MNPs-Cit. In addition, the resulting Amp-SA-M achieved ��17.2-fold higher values in r2/r1 ratios than MNPs-Cit. The enhanced performances in magnetic transverse (r2) relaxivity and r2/r1 ratio as well as the in vivo behavior of Amp-SA-M suggest the potential of Amp-SA-M as a promising MRI nanoprobe. This approach based on the nature-originated amphiphilic biopolymers may provide a novel insight into electrohydrodynamic techniques that have the ability to create various nanostructures, encapsulating high-quality hydrophobic nanomaterials for applications in diverse biotechnology.11Nsciescopu
Cloning, expression and antibacterial activity of histone H1 and its N-terminal peptide from Carassius auratus
No full text11scopu
Sandcastle Worm-Inspired Blood-Resistant Bone Graft Binder Using a Sticky Mussel Protein for Augmented In Vivo Bone Regeneration
No full textXenogenic bone substitutes are commonly used during orthopedic reconstructive procedures to assist bone regeneration. However, huge amounts of blood accompanied with massive bone loss usually increase the difficulty of placing the xenograft into the bony defect. Additionally, the lack of an organic matrix leads to a decrease in the mechanical strength of the bone-grafted site. For effective bone grafting, this study aims at developing a mussel adhesion-employed bone graft binder with great blood-resistance and enhanced mechanical properties. The distinguishing water (or blood) resistance of the binder originates from sandcastle worm-inspired complex coacervation using negatively charged hyaluronic acid (HA) and a positively charged recombinant mussel adhesive protein (rMAP) containing tyrosine residues. The rMAP/HA coacervate stabilizes the agglomerated bone graft in the presence of blood. Moreover, the rMAP/HA composite binder enhances the mechanical and hemostatic properties of the bone graft agglomerate. These outstanding features improve the osteoconductivity of the agglomerate and subsequently promote in vivo bone regeneration. Thus, the blood-resistant coacervated mussel protein glue is a promising binding material for effective bone grafting and can be successfully expanded to general bone tissue engineering.1163sciescopu
Body temperature-activated protein-based injectable adhesive hydrogel incorporated with decellularized adipose extracellular matrix for tissue-specific regenerative stem cell therapy
No full textAdipose tissue engineering represents a valuable alternative for reconstructive and cosmetic applications to restore soft tissue loss. Herein, for the development of a tissue-engineered adipose substitute, we designed an injectable thermoresponsive tissue adhesive hydrogel by grafting bioengineered mussel adhesive protein (MAP) with poly(N-isopropylacrylamide) (PNIPAM) and incorporating decellularized adipose tissue (DAT) powder as a biochemical cue. The body temperature-activated PNIPAM-grafted MAP (MAP-PNIPAM) hydrogel showed 3.2-times higher water retention ability, high porosity, and 8.4-times stronger tissue adhesive properties compared to the PNIPAM gel alone with pore collapse. Moreover, we found that the introduction of 5 wt% DAT powder had adipo-inductive and adipo-conductive effects, which might be due to the provision of biochemical substrates enriched in collagen and laminin for cell-cell and cell-matrix interactions. In vivo subcutaneous injection of the adipose-derived stem cell-laden DAT-incorporated MAP-PNIPAM hydrogel further demonstrated better volume maintenance, angiogenesis, and lipid accumulation than control injectable alginate gel or DAT powder only. Collectively, our injectable body temperature-activated tissue adhesive MAP-PNIPAM hydrogel system with a decellularized extracellular matrix source can be utilized as a promising alternative for tissue-specific regenerative stem cell therapy. Statement of Significance For adipose tissue engineering, we designed an injectable body temperature-activated adhesive hydrogel by grafting bioengineered mussel adhesive protein (MAP) with poly(N-isopropylacrylamide) (PNIPAM) and incorporating adipose-derived stem cells (ASCs) and decellularized adipose tissue (DAT) powder as regenerative cell and ECM sources. PNIPAM has been widely used for cell sheet engineering, but not for cell carriers due to its dramatic thermal contractive properties. By conjugation with hydrophilic MAP, water retention ability and tissue adhesiveness of the scaffold increased by a factor of 3.2- and 8.4-fold, respectively, which are highly required for survival of the transplanted cells and interfacial integration with host tissues. In vivo performance demonstrated that ASCs/DAT powder-laden MAP-PNIPAM hydrogel achieved better volume maintenance, neovascularization, and adipogenesis than control injectable groups. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.11Nsciescopu
Polysaccharide-Hydrophobic Nanoparticle Hybrid Nanoclusters for Enhanced Performance in Magnetic Resonance/Photoacoustic Imaging
No full textPolysaccharide-nanoparticle (NP) hybrid nanoclusters have great potential to revitalize diverse bioapplications; however, fabricating polysaccharide-based hybrid nanoclusters composed of high-quality NPs generated in the organic phase remains a challenge. Here, using calcium alginate as a polysaccharide/tetramethylammonium hydroxide (TMAOH) combination, we report a novel approach to the design of alginate-hydrophobic magnetic-plasmonic core-shell (MPCS) NP hybrid nanoclusters (A-MPCS HNCs). Furthermore, we observe the dependence of the formation of A-MPCS HNCs on the TMAOH concentration. The enhanced performance in both magnetic resonance r(2) relaxivity and photoacoustic (PA) signals and the biocompatibility/bioactivity as well as the in vivo performance of A-MPCS HNCs shows them to be a promising magnetic resonance/photoacoustic dual-mode imaging agent. Our strategy could open doors to the use of other precious high quality nanomaterials created in the organic phase via well-established synthetic chemistry in the. design of alginate-hydrophobic nanomaterial hybrid nanoclusters, giving rise to novel and multifarious bioapplications.11Nsciescopu
A sensitive paper-based lateral flow immunoassay platform using engineered cellulose-binding protein linker fused with antibody-binding domains
No full textAn advanced paper-based LFIA using engineered cellulose-binding protein linker fused with antibody-binding domains was developed to resolve problems associated with conventional LFIA strip, including the limitation of quantitative analysis and low sensitivity. CBP31-BC linker was prepared by genetically fusing the cellulose binding modules of family 3 (CBM3) and family 1 (CBM1) with antibody-binding B and C domains of Protein A. Cellulose-binding analysis showed that the addition of two CBMs led to high cellulose-binding capacity in CBP31-BC. Transmission electron microscopy and quartz crystal microbalance analyses demonstrated that the cellulose-binding ability of CBP31-BC enabled the BC domain to be efficiently exposed, allowing about 6-fold higher antibody-binding efficiency (similar to 32.5 %) than that (similar to 5.5 %) of sole BC. To evaluate the feasibility of the CBP31-BC linker-employed LFIA platform, an immunoassay of prostate-specific antigen (PSA) was performed as a model reaction. The CBP31-BC-employed paper-based LFIA detected PSA at levels as low as 0.25 ng/mL in 20 min, which is about 10-fold more sensitive to conventional LFIAs that use simple physical adsorption. CBP31-BC-employed LFIA also exhibited a lower detection range of 0.25-2.5 ng/mL when compared to conventional LFIAs. These results might be due to efficient oriented immobilization of the capture antibody by CBP31-BC linker on cellulose membrane. Thus, our developed CBP31-BC linker-employed paper-based LFIA platform holds great promise for the detection of target markers due to significantly enhanced sensitivity.11Nsciescopu
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