5,452 results match your criteria ChemBioChem [Journal]


Thioamide-bridged nucleic acid (thioAmNA) bearing thymine or 2-thiothymine: Duplex forming ability, base discrimination, and enzymatic stability.

Chembiochem 2018 Dec 14. Epub 2018 Dec 14.

Osaka University, Graduate School of Pharmaceutical Sciences, 1-6 Yamadaoka, 565-0871, Suita, JAPAN.

Because oligonucleotides containing bridged nucleic acids (BNAs) show high duplex-forming ability toward target single-stranded RNA, many BNA analogs have been developed for antisense applications. Amide-bridged nucleic acid (AmNA), which is a BNA analog bearing an amide bond at the bridge, exhibits high duplex-forming ability, enzymatic stability, and antisense activity; thus, AmNA represents a promising BNA scaffold. The high enzymatic stability of AmNA is presumably attributable to the bulky amide structure because it inhibits the access of nucleases to the phosphodiester linkage. Read More

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December 2018

Chirality Dependence of Amyloid β Cellular Uptake and a New Mechanistic Perspective.

Chembiochem 2018 Dec 14. Epub 2018 Dec 14.

UCSC, Chemistry and Biochemistry, 1156 High Street, 95064, Santa Cruz, UNITED STATES.

Amyloid β is an inherently disordered peptide that can form diverse neurotoxic aggregates, and its 42 amino acid long isoform is the believed culprit of Alzheimer's Disease. Cellular uptake of the peptide is a pivotal step for it to be able to exert many of its toxic actions. The cellular uptake process is complex, and numerous competing internalization pathways have been proposed. Read More

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December 2018
1 Read

Several Polyphosphate Kinase 2 Enzymes Produce Adenosine 5'-Polyphosphates.

Chembiochem 2018 Dec 14. Epub 2018 Dec 14.

GERMANY.

Polyphosphate kinases (PPK) are involved in many metabolic processes; enzymes of the second family (PPK2) are responsible for nucleotide synthesis under the consumption of inorganic polyphosphate. They phosphorylate nucleotides with a varying number of phosphate residues, such as monophosphates or diphosphates. Hence, these enzymes are promising candidates for cofactor regeneration systems. Read More

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December 2018

Quantitative assessment of affinity selection performance using DNA-encoded chemical libraries.

Chembiochem 2018 Dec 13. Epub 2018 Dec 13.

Philochem, Chemistry, Libernstrasse 3, 8112, Otelfingen, SWITZERLAND.

DNA-Encoded chemical libraries are often used for the discovery of ligands against protein targets of interest. These large collections of DNA-barcoded chemical compounds are typically screened by using affinity capture methodologies followed by PCR amplification and DNA sequencing procedures. However, the performance of individual steps in the selection procedures has been scarcely investigated so far. Read More

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December 2018
3.088 Impact Factor

Impacts of Cys392, Asp393, and ATP on the FAD Binding, Photoreduction, and the Stability of the Radical State of Chlamydomonas reinhardtii Cryptochrome.

Chembiochem 2018 Dec 12. Epub 2018 Dec 12.

Anhui Normal University, CHINA.

Plant cryptochromes (CRYs) are blue-light receptors that regulate the light-dependent growth, development and circadian rhythm. A flavin adenine dinucleotide (FAD) cofactor is bound to the photolyase homology region (PHR) of plant CRYs that can be photoreduced to neutral radical state under blue light. This photoreaction may trigger subsequent signal transduction. Read More

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December 2018

Fluorescent biosensor for detection of the R248Q aggregation-prone mutant of p53.

Chembiochem 2018 Dec 13. Epub 2018 Dec 13.

IBMM-UMR5247, Peptide & Proteins, Faculté de Pharmacie,15 Av. Charles Flahault, 34093, Montpellier, FRANCE.

The p53 tumour suppressor and guardian of the genome undergoes missense mutations which lead to functional inactivation in 50% human cancers. These mutations occur mostly in the DNA-binding domain of the protein and several of these induce conformational changes which lead to amyloid-like protein aggregation. Here we describe a fluorescent biosensor that reports on the R248Q mutant of p53 in vitro and in living cells, engineered through conjugation of an environmentally-sensitive probe onto a peptide derived from the primary aggregation segment of p53. Read More

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December 2018

Electronic and steric control of n→π* interactions: stabilization of the α-helix conformation without a hydrogen bond.

Chembiochem 2018 Dec 12. Epub 2018 Dec 12.

University of Delaware, Department of Chemistry and Biochemistry, 234 Brown Laboratory, 19716, Newark, UNITED STATES.

The n→π* interaction between consecutive carbonyls promotes compact conformations. In order to further understand the n→π* interaction, a series of peptides was synthesized in which the electronic and steric properties of the acyl group were modified. Using NMR spectroscopy, van't Hoff analysis, X-ray crystallography, and calculations, more electron-rich donor carbonyls were observed to promote stronger n→π* interactions and more compact conformations. Read More

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December 2018

Rational structure-based design of fluorescence probes for amyloid folds.

Chembiochem 2018 Dec 11. Epub 2018 Dec 11.

Laboratory of Physical Chemistry, Vladimir-Prelog-Weg 2, Swiss Federal Institute of, Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland, SWITZERLAND.

Amyloid fibrils are pathological hallmark of various human diseases - including Parkinson's Alzheimer's, ALS, Prion diseases. Treatment of the amyloid diseases are hindered amongst other factors also due to timely detection and therefore, early detection of the amyloid fibrils would be beneficial for the treatment against these disorders. Here, we report a small molecular fluorescent probe that selectively recognize the fibrillar form of Amyloid beta(1-42), α-Synuclein, and HET-s(218-289) protein over their monomeric conformation. Read More

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December 2018

A Covalent Inhibitor for Glutathione S-Transferase Pi (GSTP1-1) in Human Cells.

Chembiochem 2018 Dec 7. Epub 2018 Dec 7.

Nagoya University, Department of Chemistry, Graduate School of Science, Furo, Chikusa, 464-8602, Nagoya, JAPAN.

Glutathione S-transferases (GSTs) are overexpressed in several cancers and are involved in drug resistance. Therefore, GSTs are an important target in cancer therapy and many GST inhibitors have been reported. We have developed an irreversible inhibitor, GS-ESF, as an effective GST inhibitor. Read More

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December 2018

Microbial production of natural and non-natural monolignols with Escherichia coli.

Chembiochem 2018 Dec 11. Epub 2018 Dec 11.

Forschungszentrum Julich, Institute of Bio- and Geosciences, Leo-Brandt-Straße, 52425, Juelich, GERMANY.

Phenylpropanoids and phenylpropanoid-derived plant polyphenols find numerous applications in food and pharmaceutical industries. In recent years, several microbial platform organisms were engineered towards producing such compounds. However, for the most part, microbial (poly)phenol production is inspired by nature, and thus predominantly naturally occurring compounds have been produced to this date. Read More

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December 2018
3 Reads

A small cyclic β-hairpin peptide mimics of the Rbfox2 RRM that binds to the precursor miRNA 20b.

Chembiochem 2018 Dec 11. Epub 2018 Dec 11.

UNITED STATES.

The RRM (RNA-recognition motif), the most abundant RNA-binding motif in eukaryotes, is a small folded domain of about 90 amino acids, yet the β2-β3 hairpin corresponding to strands 2 and 3 of the β-sheet, and the intervening loop makes essential interactions with RNA in many RRM complexes. We designed a series of small cyclic peptides mimics of the β2-β3 hairpin of Rbfox2 protein, that recognize the terminal loop of precursor miR-20b, to investigate whether it is possible to mimic the full RNA-binding protein with a minimal structurally pre-organized peptide. Within a small library of 7 cyclic peptides, we identify a peptide with low µ-molar affinity for the miR-20b precursor. Read More

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December 2018
2 Reads

Sialyl-LacNAc-PNA∙DNA concatamers by rolling circle amplification as multivalent inhibitors for Influenza A virus particles.

Chembiochem 2018 Dec 10. Epub 2018 Dec 10.

Humboldt Universität zu Berlin, Institut ür Chemie, Brook-Taylor-Str. 2, 12489, Berlin, GERMANY.

The surface of influenza A virus (IAV) particles is packed with hundreds of homo-trimeric hemagglutinins (HA). Monovalent sugars have low affinity but distance optimized bi- or trivalent sialyl-LacNAc (SLN) conjugates bind HA with 10³─10⁴-fold enhanced potency. Herein we describe the oligomerization of distance-optimized bivalent binders by branched and linear hybridization on long repetitive DNA templates. Read More

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December 2018

A simple DNAzyme-based fluorescent assay for Klebsiella pneumoniae.

Chembiochem 2018 Dec 6. Epub 2018 Dec 6.

University of California Irvine, Pharmaceutical Sciences, Sue and Bill Gross Stem Cell Research Center, Edwards Lifesciences Center for Advanced Cardiovascular Technology, Biomedical Engineering, 92697, Irvine, UNITED STATES.

Pathogenic bacteria pose a serious public health threat. Rapid and cost effective detection of such bacteria remains a major challenge. Here, we present a DNAzyme-based fluorescent paper sensor for Klebsiella pneumoniae. Read More

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December 2018
5 Reads

Pull-down of metallated carbonic anhydrase using desthiobiotin-based probes.

Chembiochem 2018 Dec 5. Epub 2018 Dec 5.

University of Texas at Austin, Chemistry, 105 E 24th St Stop A5300, 78712, Austin, UNITED STATES.

One-third of all proteins are estimated to require metals for structural stability and/or catalytic activity. Desthiobiotin probes containing metal binding groups can be used to capture metalloproteins with exposed active-site metals under mild conditions to prevent changes in metallation state. The proof-of-concept was demonstrated with carbonic anhydrase (CA), an open active site, Zn-containing protein. Read More

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December 2018

Macromolecular crowding tunes protein stability by manipulating solvent accessibility.

Chembiochem 2018 Dec 3. Epub 2018 Dec 3.

Universitat Konstanz, Chemie, Universitaetsstraße 10, 78457, Konstanz, GERMANY.

In all intracellular processes, protein structure and dynamics are subjected to the influence of macromolecular crowding (MC). Here, the impact of different types and sizes of MC agents on the model protein BsCspB are comprehensively investigated under thermal as well as chemical denaturation. We consistently reveal a distinct stabilization of BsCspB in dependence on the MC concentration but not on viscosity, polarity or size of MC agent used. Read More

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December 2018
2 Reads

Developing an antibody-drug conjugate approach to selective inhibition of an extracellular protein.

Chembiochem 2018 Dec 3. Epub 2018 Dec 3.

LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK, UNITED KINGDOM.

Antibody-drug conjugates (ADCs) are a growing class of therapeutics, harnessing the specificity of antibodies and the cell-killing potency of small molecule drugs. Beyond cytotoxics, there are few examples of the application of an ADC approach to difficult drug discovery targets. Here, we present the initial development of a non-internalising ADC, with a view to achieving selective inhibition of an extracellular protein. Read More

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December 2018

Diffusion Profiling of Therapeutic Proteins and Peptides using Solution NMR Spectroscopy.

Chembiochem 2018 Dec 4. Epub 2018 Dec 4.

Merck and Co Inc, Merck Research Laboratories, 2000 Galloping Hill Road, 07033, Kenilworth, UNITED STATES.

Characterizing changes to structure and behavior is an important aspect of therapeutic protein development. NMR is well suited to study interactions and higher order structure that could impact biological function and safety. We employed NMR diffusion methods to describe the overall behavior of proteins in solution by defining a 'diffusion profile' that captures complexities in the diffusion behavior. Read More

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December 2018
1 Read

Impact of tetracationic calix[4]arene conformation - from conic structure to expanded bolaform- on their antibacterial and antimycobacterial activities.

Chembiochem 2018 Dec 4. Epub 2018 Dec 4.

FRANCE.

The four possible conformers of a new tetra-guanidino calix[4]arene thought to interact deleteriously with bacterial membrane were synthesized, characterized and evaluated for their in vitro antibacterial activity against various reference Gram negative and Gram positive bacteria: E. coli, P. aeruginosa, S. Read More

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December 2018
2 Reads
3.090 Impact Factor

Recognition of ASF1 Using Hydrocarbon Constrained Peptides.

Chembiochem 2018 Dec 4. Epub 2018 Dec 4.

University of Leeds, School of Chemistry, Woodhosue Lane, LS2 9JT, Leeds, UNITED KINGDOM.

Inhibition of the histone H3-ASF1 (anti-silencing function 1) protein-protein interaction (PPI) represents a potential approach for treatment of numerous cancers. As an α-helix mediated PPI, constraint of the key histone H3 helix (residues 118-135) represents a strategy through which chemical probes might be elaborated to test this hypothesis. In this work variant H3118-135 peptides bearing pentenyl glycine residues at i and i + 4 positions were constrained by olefin metathesis. Read More

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December 2018

Manipulating DNA G-Quadruplex Structures Through Guanosine Analogs.

Chembiochem 2018 Dec 4. Epub 2018 Dec 4.

Universität Greifswald, Institute of Biochemistry, D-17487, GERMANY.

The ability to control the folding topology of DNA G-quadruplexes allows for rationally designed quadruplex-based scaffolds for potential use in various therapeutic and technological applications. By exploiting the distinct conformational properties of some base and sugar modified guanosine surrogates, conformational transitions can be induced through their judicious incorporation at specific sites of the quadruplex core. Changes may involve tetrad polarity inversions with conservation of the global fold or a complete refolding to novel topologies. Read More

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December 2018

Experimental pKa Value Determination of all Ionizable Groups of a Hyper Stable Protein.

Chembiochem 2018 Dec 4. Epub 2018 Dec 4.

Martin-Luther-Universitat Halle-Wittenberg, Department of Physics, Betty-Heimann-Str. 7, 06120, Halle, GERMANY.

Electrostatic interactions significantly contribute to the stability and function of proteins. The stabilizing or destabilizing effect of local charge is reflected in the perturbation of its pKa value of an ionizable group from the intrinsic pKa value. Here we study the charge network of a hyper stable dimeric protein (rhh protein from plasmid pRN1 from Sulfolobus islandicus) through experimental determination of the pKa values of all ionizable groups. Read More

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December 2018
3 Reads

Genetic code evolution investigated through synthesis and characterisation of proteins from reduced alphabet libraries.

Chembiochem 2018 Dec 3. Epub 2018 Dec 3.

University of Minnesota, Biotechnology Institute, 1479 Gortner Ave, 140 Gortner Lab, 55108-6106, St. Paul, UNITED STATES.

The universal genetic code of 20 amino acids is the product of evolution. It is believed that earlier versions of the code comprised fewer residues. Many theories for the order in which amino acids were integrated into the code have been proposed, considering factors ranging from prebiotic chemistry to codon capture. Read More

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December 2018

Intercalating electron dyes for TEM visualization of DNA at the single-molecule level.

Chembiochem 2018 Nov 30. Epub 2018 Nov 30.

Kavli Institute of Nanoscience, Delft University of Technology, Bionanoscience, Van der Maasweg 9, 2629HZ, Delft, NETHERLANDS.

Staining compounds containing heavy elements (electron dyes) can facilitate the visualization of DNA and related biomolecules using transmission electron microscopy (TEM). However, research on the synthesis and utilization of alternative electron dyes has been limited. Here, we report the synthesis of a novel DNA intercalator molecule, bis-acridine uranyl (BAU). Read More

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November 2018
2 Reads

Synthesis and Biochemical Evaluation of Nicotinamide Derivatives as NADH analogues in Ene Reductase.

Chembiochem 2018 Nov 30. Epub 2018 Nov 30.

University of Toronto, Department of Physical and Environmental Sciences, 1265 Military Trail, M1C 1A4, Toronto, CANADA.

Nicotinamide and pyridine-containing conjugates have attracted a lot of attention in research as they have found use in a wide range of applications including as redox flow batteries, calcium channel blockers, and in biocatalysis, and metabolism. The interesting redox character of the compounds' pyridine/dihydropyridine system allows them to possess very similar, if not able to mimic, the functions and characteristics of the natural chiral redox agents NAD+/NADH. Considerable interest has been given in designing and synthesizing NAD+/NADH mimics with similar redox properties. Read More

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November 2018

Triple Orthogonal Labeling of Glycans Applying Photoclick Chemistry.

Chembiochem 2018 Nov 30. Epub 2018 Nov 30.

Universität Konstanz, Fachbereich Chemie, Universitätsstr. 10, Fach 709, 78457, Konstanz, GERMANY.

Bioorthogonal labeling of multiple biomolecules is of current interest in chemical biology. For the visualization of carbohydrates, metabolic glycoengineering (MGE) has been shown to be an appropriate approach. Here, we report that the nitrile imine-alkene cycloaddition (photoclick reaction) is a suitable ligation reaction in MGE. Read More

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November 2018
3 Reads

Mitochondria-Targeting Identification of a Fluorescent Apoptosis-Triggering Molecule by Mass Spectrometry Unravels Drug Tracking.

Chembiochem 2018 Nov 30. Epub 2018 Nov 30.

CHINA.

The real-time tracking of localization and dynamics of small molecules in organelles helps to understand their function and lock their potential targets at the subcellular resolution. To identify the mitochondria-targeting effect of small molecules (NA-17 and NA-2a) in cancer cells, we used mass spectrometry to study the distribution and enrichment of small molecules in mitochondria and the residual cytoplasm, which enables to trace action process of therapeutic molecules. Colocalization analysis with an image-guided way suggests that both NA-17 and NA-2a have mitochondria-targeting effect. Read More

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November 2018

Novel Dextran-Supported Biological Probes Decorated with Disaccharide Entities for Investigating the Carbohydrate-Protein Interactions of Gal-3.

Chembiochem 2018 Nov 30. Epub 2018 Nov 30.

Johan Gadolin Process Chemistry Centre, Laboratory of Organic Chemistry, Åbo Akademi University, 20500, Turku, Finland.

The quest for novel natural-like biomolecular probes that can be used to gain information on biological recognition events is of topical interest to several scientific areas. In particular, the recognition of carbohydrates by proteins modulates a number of important biological processes. These molecular recognition events are, however, difficult to study by the use of naturally occurring oligosaccharides and polysaccharides owing to their intrinsic structural heterogeneity and to the many technical difficulties encountered during the isolation of sufficient quantities of pure material for detailed structural and biological studies. Read More

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November 2018
1 Read

A pH-Responsive Glycyrrhetinic acid-Modified Small Molecular Conjugate for NIR Imaging of Hepatocellular Carcinoma (HCC).

Chembiochem 2018 Nov 29. Epub 2018 Nov 29.

Korea University, Department of Chemistry, Anamdong, 136-701, Seoul, KOREA, REPUBLIC OF.

Herein, we reported a glycyrrhetinic acid (GA)-decorated small molecule conjugate for pH-triggered near infra-red (NIR) fluorescence imaging of hepatocellular carcinoma (HCC). Our ''in vitro'' studies demonstrated that NIR-GA was efficiently up-taken by liver cancer cell lines such as HepG2 and Huh7 through GA receptors-mediated endocytic pathway. As suggested by co-localization studies, NIR-GA mainly localized into the lysosome where acidic pH results in activation of fluorescent dye via H+-triggered spirolactam ring opening to give strong fluorescence in NIR region. Read More

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November 2018

Mechanistic Insight into the Catalytic Promiscuity of Amine Dehydrogenases: Asymmetric Synthesis of Secondary and Primary Amines.

Chembiochem 2018 Nov 29. Epub 2018 Nov 29.

University of Amsterdam, van't Hoff Institute for Molecular Sciences, Science Park 904, 1098 XH, Amsterdam, NETHERLANDS.

Biocatalytic asymmetric aminations of ketones using amine dehydrogenases (AmDHs) or transaminases, are efficient methods for the synthesis of α-chiral primary amines. A major challenge is the extension of the amination to the synthesis of secondary and tertiary amines. Herein, we show for the first time that AmDHs are capable of accepting other amine donors, hence giving access to enantioenriched secondary amines with conversions up to 43%. Read More

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November 2018

Fast response fluorogenic probe for visualizing hypochlorite in living cells and Zebrafishes.

Chembiochem 2018 Nov 28. Epub 2018 Nov 28.

Nanjing Tech University, CHINA.

A novel fast response and visible fluorogenic probe (D1) for monitoring hypochlorite (ClO-) has been developed based on specific ClO- removal of a C=N bond. The response of the probe to ClO- showed increases linearly, and the fluorescence intensity heighten about 25 times. D1 responses to ClO- were observed with high selectivity and sensitivity within 10 s by naked eyes. Read More

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November 2018

Sesquiterpenoids Produced by the Combination of Two Sesquiterpene Cyclases with Promiscuous Myxobacterial CYP260B1.

Chembiochem 2018 Nov 28. Epub 2018 Nov 28.

Wuhan University, School of pharmaceutical science, Donghu road, No 185, 430075, Wuhan, CHINA.

Sesquiterpenes represent a class of important terpenoids with high structural diversity and a wide range of applications. The cyclized core-skeletons are generated by sesquiterpene cyclases, and the structural diversity is further increased by a series of modification steps. Cytochromes P450 (P450s) are a class of monooxygenases and one of the main contributors for the structure diversity of natural products. Read More

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November 2018

Chemical Biology of Protein N-terminal Methyltransferases.

Authors:
Rong Huang

Chembiochem 2018 Nov 26. Epub 2018 Nov 26.

Purdue University, Medicinal Chemistry and Molecular Pharmacology, 720 Clinic Drive, DRUG211, 47907, West Lafayette, UNITED STATES.

Protein α-N-terminal methylation is catalyzed by protein N-terminal methyltransferases. Prevalent occurrence of this methylation in ribosome, myosin and histones implies its function in protein-protein interaction. Although its full spectrum of function is not outlined yet, recent discovery revealed its emerging new roles in protein-chromatin interaction, DNA damage repair, and chromosome segregation. Read More

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November 2018
2 Reads

Halogen Substituents in the Isoquinoline Scaffold Switches the Selectivity of Inhibition between USP2 and USP7.

Chembiochem 2018 Nov 26. Epub 2018 Nov 26.

Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa, 3200008, Israel.

Deubiquitinases are important components of the protein regulatory network and, hence, constitute a tempting drug target. We report herein structure-activity relationship studies to develop halogen-substituted isoquionoline-1,3-dione-based inhibitors of the deubiquitinase USP2. In contrast to our previous reports, the best compound discovered was found to act through a reactive oxygen species independent, uncompetitive mechanism with an IC of 250 nm. Read More

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November 2018
1 Read

Towards Catalytic Antibiotics: Redesign of Aminoglycosides to Catalytically Disable Bacterial Ribosome.

Chembiochem 2018 Nov 25. Epub 2018 Nov 25.

Technion Israel Institute of Technology, Schulich Faculty of Chemistry, Technion City, 3200003, Haifa, ISRAEL.

The emergence of multidrug-resistant pathogens that are resistant to the majority of currently available antibiotics is a significant clinical problem. The development of new antibacterial agents and novel approaches is therefore extremely important. We set out to explore the potential of catalytic antibiotics as a new paradigm in antibiotics research. Read More

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November 2018
2 Reads

Design and Synthesis of Metabolically Stable t-RNA Synthetase Inhibitors derived from Cladosporin.

Chembiochem 2018 Nov 21. Epub 2018 Nov 21.

Novartis Institutes for BioMedical Research Basel, Chemical Biology and Therapeutic, Fabrikstrasse 22, 4056, Basel, SWITZERLAND.

Selective and specific inhibitors of Plasmodium falciparum lysyl-tRNA synthetase represent promising therapeutic antimalarial avenues. Cladosporin was identified as a potent P. falciparum lysyl-tRNA synthetase inhibitor, with an activity against parasite lysyl-tRNA synthetase >100-fold more potent than the activity registered against the human enzyme. Read More

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November 2018
4 Reads

Influence of Linker length on Ligase-Catalyzed Oligonucleotide Polymerization.

Chembiochem 2018 Nov 20. Epub 2018 Nov 20.

York University, Chemistry, 4700 Keele Street, M3J 1P3, Toronto, CANADA.

Ligase-catalyzed oligonucleotide polymerization (LOOPER) has been recently developed to enable the sequence-defined generation of DNA with up to 16 different modifications. This approach was used to evolve new classes of diversely-modified DNA aptamers for molecular recognition. The modifications in LOOPER are appended via a long hexamethylenediamine linker, which could negatively impact binding thermodynamics. Read More

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November 2018
1 Read

Efficient Cytoplasmic Delivery of Antisense Probes Assisted by Cyclized Peptide-mediated Photo-induced Endosomal Escape.

Chembiochem 2018 Nov 19. Epub 2018 Nov 19.

UNITED STATES.

Intracellular delivery and endosomal release of antisense oligonucleotides remain a significant challenge in the development of gene-targeted therapeutics. Previously, non-covalently cyclized TAT peptide (Cyc-TAT), in which the final ring-closing step is accomplished by hybridization of two short complementary γPNA segments, has been proven more efficient than its linear analogues to enter cells. Since Cyc-TAT also readily accommodates a binding site, i. Read More

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November 2018
3 Reads

Terminal deoxynucleotidyl transferase in synthesis and modification of nucleic acids.

Chembiochem 2018 Nov 19. Epub 2018 Nov 19.

Institut Pasteur, Department of Structural Biology and Chemistry, 28 Rue du Dr. Roux, 75015, Paris, FRANCE.

The terminal deoxynucleotidyl transferase (TdT) belongs to the X Family of DNA polymerases. This unusual polymerase catalyzes the template-independent addition of random nucleotides on 3'-overhangs during V(D)J recombination. The biological function and intrinsic biochemical properties of the TdT have spurred the development of numerous oligonucleotide-based tools and methods especially when combined with modified nucleoside triphosphates. Read More

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November 2018

Tracking conformational changes in phosvitin throughout a crowding agent based titration.

Chembiochem 2018 Nov 19. Epub 2018 Nov 19.

University of Antwerp, Department of Chemistry, Groenenborgerlaan 171, B2020, Antwerp, BELGIUM.

In this paper, the sensitivity of Raman optical activity (ROA) towards small conformational changes is explored by tracking the structural changes in an intrinsically disordered protein, phosvitin, caused by different concentrations of crowding agent. It is shown that ROA is capable of tracking small conformational changes towards beta-sheet and alpha-helical secondary structural properties of the protein. Furthermore, it is indicated that the influence of the crowding agents Ficoll 70 and dextran 70 used on the structural properties of phosvitin differs significantly, with the structural changes induced by the presence of Ficoll 70 being more pronounced and being already visible at a lower concentration. Read More

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November 2018

INH14, a small-molecule urea derivative, inhibits the IKKα/β-dependent TLR inflammatory response.

Chembiochem 2018 Nov 17. Epub 2018 Nov 17.

Medizinische Universitat Innsbruck, Biochemische Pharmakologie, Peter Mayr Str. 1, 6020, Innsbruck, AUSTRIA.

INH14 (N-(4-ethylphenyl)-N'-phenylurea) is a fragment-like compound that inhibits the Toll-like receptor 2 (TLR2)-mediated inflammatory activity and also other inflammatory pathways (i.e. TLR4, TNF-R and IL-1R). Read More

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November 2018
2 Reads
3.088 Impact Factor

Light-triggered Covalent Assembly of Gold Nanoparticles for Cancer Cell Photothermal Therapy.

Chembiochem 2018 Nov 17. Epub 2018 Nov 17.

Soochow university, School of Radiation Medicine and Protection, 199 Renai Road, Industrial Park, 215123, Suzhou, CHINA.

Manipulating the assembly of gold nanoparticles (AuNPs) for maximizing the photothermal effect is a promising strategy for cancer therapy. Herein, taking advantage of the well-known tetrazole/alkene photo-click chemistry, we for the first time demonstrated that small AuNPs (23 nm) decorated with both 2, 5-diphenyltetrazole and methacrylic acid on the surface could form covalently cross-linked aggregates upon laser irradiation (λ = 405 nm). The in vitro studies indicated that the light-triggered assembling remarkably shifted the surface plasmon resonance of AuNPs to near-infrared (NIR) regions, which in consequence effectively enhanced the efficacy of photothermal therapy for 4T1 breast cancer cells. Read More

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November 2018
7 Reads

R-ɷ-Transaminase Covalently Linking to D-Amino Acid Oxidase Through Protein Splicing to Enhance Enzymatic Catalysis of Transamination of Amines.

Chembiochem 2018 Nov 16. Epub 2018 Nov 16.

CHINA.

R-ɷ-Transaminases (RTA) catalyze the conversion of (R)-amines (e.g. (R)-1-phenylethylamine) to corresponding ketones (e. Read More

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November 2018
1 Read

Reactivity of the Major Product of C5'-Oxidative DNA Damage in Nucleosome Core Particles.

Chembiochem 2018 Nov 16. Epub 2018 Nov 16.

Johns Hopkins University, Department of Chemistry, 3400 N. Charles St., 21218, Baltimore, UNITED STATES.

The major pathway for DNA damage following hydrogen atom abstraction from the C5'-position results in direct strand scission and concomitant formation of a 5'-aldehyde containing nucleotide (e.g. T-al). Read More

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November 2018
3 Reads

Induction of Nectriapyrone Biosynthesis in the Rice Blast Fungus Pyricularia oryzae by Disturbance of the Two-Component Signal Transduction System.

Chembiochem 2018 Nov 15. Epub 2018 Nov 15.

RIKEN, JAPAN.

Most fungal secondary metabolism genes are poorly expressed under laboratory conditions. Nectriapyrones are known as secondary metabolites produced mainly by symbiotic fungi, including endophytes and plant pathogens. Here, we show the induction of nectriapyrone production in the rice blast fungus Pyricularia oryzae. Read More

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November 2018
1 Read

From bugs to bioplastics: Total (+)-dihydrocarvide biosynthesis by engineered Escherichia coli.

Chembiochem 2018 Nov 15. Epub 2018 Nov 15.

Manchester Institute of Biotechnology, Faculty fo Life Sciences, 131 Princess Street, M1 7DN, Manchester, UNITED KINGDOM.

The monoterpenoid lactone derivative (+)-dihydrocarvide ((+)-DHCD) can be polymerised to form shape memory polymers. Synthetic biology routes from simple, inexpensive carbon sources are an attractive, alternative route over chemical synthesis from (R)-carvone. We have demonstrated a 'proof of principle' in vivo approach for the complete biosynthesis of (+)-DHCD from glucose in E. Read More

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November 2018
4 Reads

PRMT1-dependent Labeling and Isolation of Histone H4 Through N-Mustard Analogs of S-Adenosyl-L-methionine.

Chembiochem 2018 Nov 14. Epub 2018 Nov 14.

Wake Forest University, Department of Chemistry, 455 Vine St, Wake Downtown, 27101-4135, United States, 27101, Winston Salem, UNITED STATES.

Histones, the fundamental building blocks of nucleosomes, undergo post-translational modifications and play a major role in the regulation of transcriptional processes. While the significance of these modifications, including methylation, is widely recognized, little is known about the mechanisms that link such events. To improve our understanding of how protein methylation is intricately linked, we have developed novel N-mustard analogs of S-adenosyl-L-methionine (SAM) functionalized with azides and alkynes to serve as probes of biological methylation. Read More

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November 2018

Strategy and Effects of Polyproline Peptide Stapling by Copper(I)-catalyzed Alkyne-azide Cycloaddition Reaction.

Chembiochem 2018 Nov 14. Epub 2018 Nov 14.

National Tsing Hua University, Chemistry department, 101, Sec. 2, Kuang-Fu Rd., 30013, Hsinchu, TAIWAN.

Polyproline is a unique type of peptide that exhibits a stable, robust and well-defined helical structure in an aqueous environment. These features have allowed polyproline to be employed as a nano-sized scaffold for applications in chemical biology and related fields. To understand its structural properties and to expand the applications, this secondary structure was tested systematically by stapling the peptide at different locations with various staple lengths. Read More

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November 2018
6 Reads

Accurate Determination of Human CPR Conformational Equilibrium by smFRET using Dual Orthogonal Non-Canonical Amino Acid Labeling.

Chembiochem 2018 Nov 14. Epub 2018 Nov 14.

LISBP, Université de Toulouse, CNRS, INRA, INSA 135 Avenue de Rangueil, 31077, Toulouse, (FRANCE), FRANCE.

Conjugation of fluorescent dyes to proteins - a prerequisite for the study of conformational dynamics by single molecule Förster resonance energy transfer (smFRET) - can lead to substantial changes of the dye's photophysical properties, ultimately biasing the determination of inter-dye distances. In particular, cyanine dyes and their derivatives, the most used dyes in smFRET experiments, exhibit such behavior. To overcome this, we developed a general strategy to site-specifically equip proteins with FRET pairs by chemo-selective reactions using two distinct non-canonical amino acids simultaneously incorporated through genetic code expansion in Escherichia coli. Read More

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November 2018
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Automated Glycan Assembly of Plant Oligosaccharides and Their Application in Cell Wall Biology.

Chembiochem 2018 Nov 14. Epub 2018 Nov 14.

Max-Planck-Institute of Colloids and Interfaces, Biomolecular Systems, Am Mühlenberg 1, 14476, Potsdam, GERMANY.

The plant cell wall provides the richest available resource of fermentable carbohydrates and bio-based materials. The main component of plant cell walls is cellulose, the most abundant biomolecule on earth. Besides cellulose, which is constructed from relatively simple β-1,4-glucan chains, plant cell walls also contain the structurally more complex heteropolysaccharides hemicellulose and pectin, as well as lignin and cell wall proteins. Read More

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November 2018

Improved efficacy of antibody cancer immunotherapeutics through local and sustained delivery.

Chembiochem 2018 Nov 13. Epub 2018 Nov 13.

McMaster University, Chemistry and Chemical Biology, 1280 Main St. W., ABB-261A, L8S 4M1, Hamilton, CANADA.

Antibodies are a growing class of cancer immunotherapeutics that facilitate immune cell mediated killing of tumors. However, the efficacy and safety of immunotherapeutics are limited by transport barriers and poor tumor uptake, which leads to high systemic concentrations and potentially fatal side effects. To increase tumor antibody immunotherapeutic concentrations while decreasing systemic concentrations, local delivery vehicles for sustained antibody release are being developed. Read More

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November 2018
4 Reads