Bioinspired synthesis of virus-like particle-templated thin silica-layered nanocages with enhanced biocompatibility and cellular uptake as drug delivery carriers.

The bioinspired synthesis of virus-like silica nanoparticles in biomedical applications makes it possible to utilize the cellular delivery capabilities of viruses while minimizing the cytotoxicity of inorganic silica. In this study, we developed a diatom-inspired method for synthesizing silica-layered nanocages utilizing R5 peptide-functionalized virus-like particles (VLPs). R5 peptides were genetically inserted into the F-G loop of human papillomavirus 16 L1 proteins (HPV16 L1-R5).

Genetically engineered bacteriophages as novel nanomaterials: applications beyond antimicrobial agents.

Bacteriophages, also known as phages, are viruses that replicate in bacteria and archaea. Phages were initially discovered as antimicrobial agents, and they have been used as therapeutic agents for bacterial infection in a process known as "phage therapy." Recently, phages have been investigated as functional nanomaterials in a variety of areas, as they can function not only as therapeutic agents but also as biosensors and tissue regenerative materials.

Virus-like nanoparticles as a theranostic platform for cancer.

Virus-like nanoparticles (VLPs) are natural polymer-based nanomaterials that mimic viral structures through the hierarchical assembly of viral coat proteins, while lacking viral genomes. VLPs have received enormous attention in a wide range of nanotechnology-based medical diagnostics and therapies, including cancer therapy, imaging, and theranostics. VLPs are biocompatible and biodegradable and have a uniform structure and controllable assembly.

A colorimetric lateral flow immunoassay based on oriented antibody immobilization for sensitive detection of SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). The high human-to-human transmission and rapid evolution of SARS-CoV-2 have resulted in a worldwide pandemic. To contain SARS-CoV-2, it is essential to efficiently control the transmission of the virus through the early diagnosis of infected individuals, including asymptomatic people.

Bone Graft Biomineral Complex Coderived from Marine Biocalcification and Biosilicification.

Bone graft materials have been mainly developed based on inorganic materials, including calcium phosphate. However, these graft materials usually act as osteoconductive rather than osteoinductive scaffolds. To improve bone reconstruction, a combination of several materials has been proposed.

Glycan chip based on structure-switchable DNA linker for on-chip biosynthesis of cancer-associated complex glycans.

On-chip glycan biosynthesis is an effective strategy for preparing useful complex glycan sources and for preparing glycan-involved applications simultaneously. However, current methods have some limitations when analyzing biosynthesized glycans and optimizing enzymatic reactions, which could result in undefined glycan structures on a surface, leading to unequal and unreliable results. In this work, a glycan chip is developed by introducing a pH-responsive i-motif DNA linker to control the immobilization and isolation of glycans on chip surfaces in a pH-dependent manner.

Expression and purification of the full-length N-acetylgalactosaminyltransferase and galactosyltransferase from Campylobacter jejuni in Escherichia coli.

The successful enzymatic synthesis of various ganglioside-related oligosaccharides requires many available glycan-processing enzymes. However, the number of available glycan-processing enzymes remains limited. In this study, the full-length CgtA43456 (β-(1→4)-N-acetylgalactosaminyltransferase) and CgtB11168 (β-(1→3)-galactosyltransferase) were successfully produced from Escherichia coli through the optimization of E.

Enzyme immobilization on porous chitosan hydrogel capsules formed by anionic surfactant gelation.

Objectives: Sodium dodecyl sulfate (SDS)-chitosan hydrogels have been employed for adsorption of anionic dyes and metallic substances. Two mutant forms of Thermoanaerobacter ethanolicus alcohol dehydrogenase (TeSADH) were used as model enzymes to develop a novel enzyme immobilization technique employing newly formulated porous chitosan hydrogels.

Results: The enzyme immobilized on chitosan hydrogel capsules formed by 5 g/l SDS gelation and subsequent treatment with 0.

Coexpression of CMP-sialic acid transporter reduces N-glycolylneuraminic acid levels of recombinant glycoproteins in Chinese hamster ovary cells.

Recombinant glycoproteins expressed in Chinese hamster ovary (CHO) cells contain two forms of sialic acids; N-acetylneuraminic acid (Neu5Ac) as a major type and N-glycolylneuraminic acid (Neu5Gc) as a minor type. The Neu5Gc glycan moieties in therapeutic glycoproteins can elicit immune responses because they do not exist in human. In the present work, to reduce Neu5Gc levels of recombinant glycoproteins from CHO cell cultures, we coexpressed cytidine-5'-monophosphate-sialic acid transporter (CMP-SAT) that is an antiporter and transports cytosolic CMP-sialic acids (both forms) into Golgi lumen.

Impact of Expanded Small Alkyl-Binding Pocket by Triple Point Mutations on Substrate Specificity of Thermoanaerobacter ethanolicus Secondary Alcohol Dehydrogenase.

Site-directed mutagenesis was employed to generate five different triple point mutations in the double mutant (C295A/I86A) of alcohol dehydrogenase (TeSADH) by computer-aided modeling with the aim of widening the small alkyl-binding pocket. TeSADH engineering enables the enzyme to accept sterically hindered substrates that could not be accepted by the wild-type enzyme. The underline in the mutations highlights the additional point mutation on the double mutant TeSADH introduced in this work.

On-chip biosynthesis of GM1 pentasaccharide-related complex glycans.

A functional glycan chip combined with on-chip enzymatic glycosylation was developed to prepare complex glycan sources and to apply glycan-involved applications simultaneously. GM3 trisaccharide, GM2 tetrasaccharide, and GM1 pentasaccharide were successfully directly biosynthesized on lactose-immobilized surfaces through three consecutive glycosyltransferase reactions along with small amounts of enzymes and donors, without any additional processes. Biosynthesized GM1 pentasaccharide-related complex glycans were demonstrated to provide information on the substrate specificity of whole cholera toxin.

Diatom-Inspired Silica Nanostructure Coatings with Controllable Microroughness Using an Engineered Mussel Protein Glue to Accelerate Bone Growth on Titanium-Based Implants.

Silica nanoparticles (SiNPs) have been utilized to construct bioactive nanostructures comprising surface topographic features and bioactivity that enhances the activity of bone cells onto titanium-based implants. However, there have been no previous attempts to create microrough surfaces based on SiNP nanostructures even though microroughness is established as a characteristic that provides beneficial effects in improving the biomechanical interlocking of titanium implants. Herein, a protein-based SiNP coating is proposed as an osteopromotive surface functionalization approach to create microroughness on titanium implant surfaces.

Mutagenesis of Met-151 and Thr-153 to alanine in Thermoanaerobacter ethanolicus secondary alcohol dehydrogenase changes substrate specificity for acetophenones.

Secondary alcohol dehydrogenase (SADH) from Thermoanaerobacter ethanolicus reduces ketones to chiral alcohols, and generally obeys Prelog's Rule, with binding pockets for large and small alkyl substituents, giving (S)-alcohols. We have previously shown that mutations in both the large and small pockets can alter both substrate specificity and stereoselectivity. In the present work, Met-151 and Thr-153, residues located in the small pocket, were mutated to alanine.

I86A/C295A mutant secondary alcohol dehydrogenase from Thermoanaerobacter ethanolicus has broadened substrate specificity for aryl ketones.

Thermoanaerobacter ethanolicus secondary alcohol dehydrogenase (SADH) reduces aliphatic ketones according to Prelog's Rule, with binding pockets for small and large substituents. It was shown previously that the I86A mutant SADH reduces acetophenone, which is not a substrate of wild-type SADH, to give the anti-Prelog R-product (Musa, M. M.

Versatile signal peptide of Flavobacterium-originated organophosphorus hydrolase for efficient periplasmic translocation of heterologous proteins in Escherichia coli.

Organophosphorus hydrolase (OPH) from Flavobacterium species is a membrane-associated homodimeric metalloenzyme and has its own signal peptide in its N-terminus. We found that OPH was translocated into the periplasmic space when the original signal peptide-containing OPH was expressed in recombinant Escherichia coli even though its translocation efficiency was relatively low. To investigate the usability of this OPH signal peptide for periplasmic expression of heterologous proteins in an E.

Hybrid microarray based on double biomolecular markers of DNA and carbohydrate for simultaneous genotypic and phenotypic detection of cholera toxin-producing Vibrio cholerae.

Life-threatening diarrheal cholera is usually caused by water or food contaminated with cholera toxin-producing Vibrio cholerae. For the prevention and surveillance of cholera, it is crucial to rapidly and precisely detect and identify the etiological causes, such as V. cholerae and/or its toxin.

Mechanically Durable and Biologically Favorable Protein Hydrogel Based on Elastic Silklike Protein Derived from Sea Anemone.

As biodegradable scaffolds, protein hydrogels have considerable potential, particularly for bioartificial organs and three-dimensional space-filling materials. However, their low strength and stiffness have been considered to be limitations for enduring physiological stimuli. Therefore, protein hydrogels have been commonly utilized as delivery vehicles rather than as supporting materials.

Optical detection of paraoxon using single-walled carbon nanotube films with attached organophosphorus hydrolase-expressed Escherichia coli.

In whole-cell based biosensors, spectrophotometry is one of the most commonly used methods for detecting organophosphates due to its simplicity and reliability. The sensor performance is directly affected by the cell immobilization method because it determines the amount of cells, the mass transfer rate, and the stability. In this study, we demonstrated that our previously-reported microbe immobilization method, a microbe-attached single-walled carbon nanotube film, can be applied to whole-cell-based organophosphate sensors.

Rg3-enriched Korean Red Ginseng improves vascular function in spontaneously hypertensive rats.

Background: Panax ginseng has distinct and impressive health benefits, such as improved blood pressure and immune system functioning. Rg3-enriched Korean Red Ginseng (REKRG) isolated from Korean Red Ginseng contains a high percentage of Rg3.

Methods: In this study, we examined the effects of REKRG on endothelial cell nitric oxide synthase (eNOS) activation and adhesion molecules in endothelial cells and vascular function in rats.

A nonfusogenic antigen mimic of influenza hemagglutinin glycoproteins constituted with soluble full-length HA1 and truncated HA2 proteins expressed in E. coli.

A novel method is proposed to produce a soluble recombinant antigen mimic, constituted with full-length HA1 and truncated HA2 individually expressed in E. coli, instead of a precursor form of hemagglutinin protein, that is similar to the naturally processed and disulfide-linked HA1/HA2 on the envelope of the influenza A virus strain X-31 (H3N2). A truncated ectodomain of HA2 subunit, HA2(23-185)/C137S, lacked two membrane-interacting sequences, i.

Engineered whole-cell biocatalyst-based detoxification and detection of neurotoxic organophosphate compounds.

The development of efficient tools is required for the eco-friendly detoxification and effective detection of neurotoxic organophosphates (OPs). Although enzymes have received significant attention as biocatalysts because of their high specific activity, the uneconomic and labor-intensive processes of enzyme production and purification make their broad use in practical applications difficult. Because whole-cell systems offer several advantages compared with free enzymes, including high stability, a reduced purification requirement, and low preparation cost, they have been suggested as promising biocatalysts for the detoxification and detection of OPs.

Association between Hepatitis B Surface Antigen Seropositivity and Metabolic Syndrome.

Background: Infection with hepatitis B virus (HBV) may be a risk factor for cardiovascular disease. We investigated the relationship between HBV infection and metabolic syndrome.

Methods: We performed a cross-sectional study of 9,474 Korean men and women who were at least 20 years old and who underwent a routine health check-up at Ulsan University Hospital in Ulsan, South Korea between March 2008 and February 2009.

Structural evaluation of GM1-related carbohydrate-cholera toxin interactions through surface plasmon resonance kinetic analysis.

Surface plasmon resonance (SPR) can provide kinetic information about an interaction, and it can also be used to rapidly monitor dynamic processes, such as adsorption and degradation, without the need for sample labeling. Here, we employed SPR to analyze carbohydrate-protein interactions, particularly GM1-related carbohydrate-Vibrio cholera toxin interactions. The interaction between cholera toxin subunits A (ctxA) and B (ctxB) was similar to general ligand-receptor interactions.

Investigation of protein expression profiles of erythritol-producing Candida magnoliae in response to glucose perturbation.

Protein expression patterns of an erythritol-producing yeast, Candida magnoliae, were analyzed to identify differentially expressed proteins in response to glucose perturbation. Specifically, wild type C. magnoliae was grown under high and low glucose conditions and the cells were harvested at both mid-exponential and erythritol production phases for proteomic studies.

Effects of oxygen supply and mixed sugar concentration on D-ribose production by a transketolase-deficient Bacillus subtilis SPK1.

D-Ribose is a value-added five-carbon sugar used for riboflavin production. To investigate the effects of oxygen supply and mixed sugar concentration on microbial production of D-ribose, a transketolase-deficient Bacillus subtilis SPK1 was cultured batch-wise using xylose and glucose. A change of agitation speed from 300 rpm to 600 rpm at 1 vvm of air supply increased both the xylose consumption rate and D-ribose production rate.