5,520 results match your criteria ChemBioChem [Journal]


Ordered and Isomerically-Stable Bicyclic Peptide Scaffolds Constrained through Cystine Bridges and Proline Turns.

Chembiochem 2019 Feb 15. Epub 2019 Feb 15.

Xiamen University, College of Chemistry and Chemical Engineering, Siming south road, 361005, Xiamen, CHINA.

Bicyclic peptides are attractive scaffolds for the design of potent protein binders and new therapeutics. However, peptide bicycles constrained through disulfides are rarely stable or tolerant to sequence manipulation due to disulfide isomerizations, especially for peptides lack of regular secondary structures. In this work, we report the discovery and identification of a class of bicyclic peptide scaffolds with ordered but irregular secondary structures. Read More

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http://dx.doi.org/10.1002/cbic.201800788DOI Listing
February 2019

Combining chemical synthesis and enzymatic methylation to access short RNAs with various 5' caps.

Chembiochem 2019 Feb 15. Epub 2019 Feb 15.

University of Muenster, Department of Chemistry, Institute for Biochemistry, Wilhelm-Klemm Strasse 2, 48149, Muenster, GERMANY.

Eukaryotic RNAs are heavily processed including co- and post-transcriptional formation of various 5' caps. In snRNAs and snoRNAs the canonical m7G cap is hypermethylated at the N2-position while in higher eukaryotes and viruses 2'-O-methylation of the first transcribed nucleotide yields the cap1 structure. The function and potential dynamics of several RNA-cap modifications has not been fully elucidated, necessitating preparative access to these caps. Read More

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http://dx.doi.org/10.1002/cbic.201900037DOI Listing
February 2019

A concise, modular antibody-oligonucleotide conjugation strategy based on disuccinimidyl ester activation chemistry.

Chembiochem 2019 Feb 14. Epub 2019 Feb 14.

University of Chicago, Chemistry, 929 E. 57th Street, GCIS E505, 60637, Chicago, UNITED STATES.

Synthesis of antibody-oligonucleotide conjugates has enabled the development of highly sensitive bioassays for specific epitopes in the laboratory and clinic. Most synthetic schemes to generate these hybrid molecules require expensive reagents, significant quantities of input antibody, and multi-step purification routes, thus limiting widespread application. Here we report a facile and robust conjugation strategy that involves "plug-and-play" antibody conjugation with succinimidyl-functionalized oligonucleotides, which are high-yielding and compatible for use directly after buffer exchange. Read More

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http://dx.doi.org/10.1002/cbic.201900027DOI Listing
February 2019

Novel Old Yellow Enzyme Subclasses.

Chembiochem 2019 Feb 13. Epub 2019 Feb 13.

Zurcher Hochschule fur Angewandte Wissenschaften, Life Sciences and Facility Management, Einsiedlerstrasse 31, 8820, Wädenswil, SWITZERLAND.

Many drug candidate molecules contain at least one chiral centre and consequently, the development of biocatalytic strategies to complement existing metal- and organocatalytic approaches is of high interest. However, time is a critical factor in chemical process development and thus, the introduction of biocatalytic steps, even if more suitable, is often prevented by the limited availability of off-the-shelf enzyme libraries. To expand the biocatalytic toolbox with additional ene reductases, we screened 19 bacterial strains for double bond reduction activity using the model substrates cyclohexanone and carvone. Read More

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http://doi.wiley.com/10.1002/cbic.201800770
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http://dx.doi.org/10.1002/cbic.201800770DOI Listing
February 2019
6 Reads

A Phosphinate-Containing Fluorophore Capable of Selectively Inducing Apoptosis in Cancer Cells.

Chembiochem 2019 Feb 12. Epub 2019 Feb 12.

University of Nebraska-Lincoln, Department of Chemistry, 409D Hamilton Hall, 68588, Lincoln, UNITED STATES.

Chemotherapeutic agents generally suffer from off-target cytotoxicity in noncancerous cell types, leading to undesired side effects. As a result, significant effort has been put into identifying compounds that are selective for cancerous versus noncancerous cell types. Our lab has recently developed a series of near-infrared (NIR) fluorophores containing a phosphinate functionality at the bridging position of the xanthene scaffold, termed Nebraska Red (NR) fluorophores. Read More

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http://dx.doi.org/10.1002/cbic.201800811DOI Listing
February 2019

Fluorescence Properties of Flavin Semiquinone Radicals in Nitronate Monooxygenase.

Chembiochem 2019 Feb 12. Epub 2019 Feb 12.

Georgia State University, UNITED STATES.

Fluorescent cofactors like flavins can be exploited to probe their local environment with spatial and temporal resolution. While the fluorescence properties of oxidized and two-electron reduced states of flavins have been studied extensively, this is not the case for the one-electron reduced state. Both the neutral and anionic semiquinones have proven particularly challenging to examine, as they are unstable in solution and are transient, short-lived species in many catalytic cycles. Read More

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http://dx.doi.org/10.1002/cbic.201900016DOI Listing
February 2019

Peptides Containing meso-Oxa-Diaminopimelic Acid as Substrates for the Cell Shape-Determining Proteases Csd6 and Pgp2.

Chembiochem 2019 Feb 11. Epub 2019 Feb 11.

University of British Columbia, Chemistry, 2036 Main Mall, V6T 1Z1, Vancouver, CANADA.

The enzymes Csd6 and Pgp2 are peptidoglycan (PG) proteases found in the pathogenic bacteria Helicobacter pylori and Campylobacter jejuni, respectively. These enzymes are involved in the trimming of uncrosslinked PG sidechains and catalyze the cleavage of the bond between meso-diaminopimelic acid (meso-Dap) and D-alanine, thus converting a PG-tetrapeptide into a PG-tripeptide. They are known to be cell shape-determining enzymes, since deletion of the corresponding genes result in mutant strains that have lost the normal helical phenotype and instead possess a straight rod morphology. Read More

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http://dx.doi.org/10.1002/cbic.201900011DOI Listing
February 2019

Cross-Isotopic Bioorthogonal Tools as Molecular Twins for Radiotheranostic Applications.

Chembiochem 2019 Feb 11. Epub 2019 Feb 11.

Vienna University of Technology, Institute of Applied Synthetic Chemistry, Getreidemarkt 9/163-OC, 1060, Vienna, AUSTRIA.

Radiotheranostics are designed by labeling targeting (bio)molecules with radionuclides for diagnostic or therapeutic application. As the pharmacokinetics of therapeutic compounds play a pivotal rule, chemically closely related imaging agents are used to evaluate the overall feasibility of the therapeutic approach. 'Theranostic relatives' utilizing different elements are frequently used in clinical practice. Read More

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http://dx.doi.org/10.1002/cbic.201900042DOI Listing
February 2019

Towards reverse transcription with an expanded genetic alphabet.

Chembiochem 2019 Feb 11. Epub 2019 Feb 11.

University of Bonn, Limes Institute, Chemical Biology & Medicinal Chemistry Unit, Gerhard-Domagk-Strasse 1, 53121, Bonn, GERMANY.

Unnatural base pairs (UBPs) strikingly augment the natural genetic alphabet and the development of particular hydrophobic unnatural base pairs even allows insertion and stable propagation in bacteria. Those UBPs expand the chemical scope of DNA and RNA and thus could enable evolving novel aptamers or ribozymes by in vitro selection (SELEX). However, application of such UBPs in reverse transcription (rtc), which is a key step for RNA-based SELEX, has not been reported so far. Read More

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http://dx.doi.org/10.1002/cbic.201800808DOI Listing
February 2019

A 'quenchergenic' chemoselective protein labeling strategy.

Chembiochem 2019 Feb 10. Epub 2019 Feb 10.

Boston college, Chemistry, 2609 Beacon Street, 246B Merkert, 02467, Chestnut hill, UNITED STATES.

Dynamic changes in protein structure can be monitored using a fluorescent probe and a dark quencher. This approach is contingent upon the ability to precisely introduce a fluorophore/quencher pair into two specific sites of a protein of interest. Despite recent advances, there is continued demand for new and convenient approaches to site-selectively label proteins with such optical probes. Read More

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http://dx.doi.org/10.1002/cbic.201800817DOI Listing
February 2019

Small Molecule Inhibitors of the Proteasome's Regulatory Particle.

Chembiochem 2019 Feb 10. Epub 2019 Feb 10.

Purdue University, Medicinal Chemistry, 575 W. Stadium Ave, RHPH 506A, 47907, West Lafayette, UNITED STATES.

Cells need to consistently synthesize and degrade proteins. Maintaining a balanced level of protein in the cell requires a carefully controlled system and significant energy. Degradation of unwanted or damaged proteins into smaller peptide units can be accomplished by the proteasome. Read More

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http://dx.doi.org/10.1002/cbic.201900017DOI Listing
February 2019
1 Read

Photoactivable elimination of tumorigenic human induced pluripotent stem cells using a lectin-doxorubicin prodrug conjugate.

Chembiochem 2019 Feb 8. Epub 2019 Feb 8.

National Institute of Advanced Industrial Science and Technology, Biotechnology Research Institute for Drug Discovery, Tsukuba Central 2, 1-1-1 Umezono, 305-8568, Tsukuba, JAPAN.

Human pluripotent stem cells (hPSCs) are attractive resources for regenerative medicine but medical applications are hindered by their tumorigenic potential. Previously, we identified a hPSC-specific lectin probe, rBC2LCN, through comprehensive glycome analysis using high-density lectin microarrays. Here, we developed a lectin-doxorubicin (DOX) prodrug conjugate with controllable photolysis activation for the elimination of tumorigenic human induced pluripotent stem cells. Read More

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http://dx.doi.org/10.1002/cbic.201900086DOI Listing
February 2019

Efficient Enzymatic Cyclization of Disulfide-rich Peptides using Peptiligases.

Chembiochem 2019 Feb 8. Epub 2019 Feb 8.

EnzyPep BV, R&D, Urmonderbaan 22, 6167RD, 6167RD, NETHERLANDS.

Disulfide-rich macrocyclic peptides, e.g. cyclotides, represent a promising class of molecules with potential therapeutic use. Read More

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http://dx.doi.org/10.1002/cbic.201900033DOI Listing
February 2019
1 Read

Genome-scale CRISPR/Cas9 screening revealed squalene epoxidase as susceptibility factor for cytotoxicity of malformin A1.

Chembiochem 2019 Feb 8. Epub 2019 Feb 8.

JAPAN.

Malformin A1 (MA1) is a fungus-produced cyclic pentapeptide. MA1 exhibits teratogenicity to plants, fibrinolysis-enhancing activity, and cytotoxicity to mammalian cells. To clarify the cytotoxic mechanism of MA1, we screened for the genes involved in the cytotoxicity of MA1 in monocytoid U937 cells by using CRISPR/Cas9-based genome-wide knockout library. Read More

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http://dx.doi.org/10.1002/cbic.201800769DOI Listing
February 2019

Higher order structures based on molecular interactions for the formation of natural and artificial biomaterials.

Chembiochem 2019 Feb 7. Epub 2019 Feb 7.

RWTH Aachen University, Institute of Inorganic Chemistry, Landoltweg 1, 52074, Aachen, GERMANY.

The assembly of molecular building blocks into highly ordered structures is crucial, both in nature and for the development of novel functional materials. In nature, non-covalent interactions such as hydrogen bonds or hydrophobic interactions enable the reversible assembly of biopolymers such as DNA or proteins. Inspired by these design principles, scientists have created biohybrid materials that employ natural building blocks and their assembly properties. Read More

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http://dx.doi.org/10.1002/cbic.201800824DOI Listing
February 2019

Protein Microarray Copying - Easy on-demand protein microarray generation compatible with fluorescence as well as label-free real-time analysis.

Chembiochem 2019 Feb 7. Epub 2019 Feb 7.

Albert-Ludwigs-Universitat Freiburg, GERMANY.

Protein microarrays are essential to understand complex protein interaction networks. Their production, however, is a challenge rendering this technology unattractive for many laboratories. Recent developments in cell-free protein microarray generation offer new opportunities, but are still expensive and cumbersome in practice. Read More

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http://dx.doi.org/10.1002/cbic.201800699DOI Listing
February 2019

Towards the native binding modes of Lipid II targeting antibiotics.

Chembiochem 2019 Feb 6. Epub 2019 Feb 6.

Universiteit Utrecht, Pandualaan 8, NETHERLANDS.

The alarming rise of antimicrobial resistance (AMR) imposes severe burdens on health care systems and the economy worldwide, urgently calling for the development of novel antibiotics. Antimicrobial peptides could be ideal templates for next-generation antibiotics due to their low propensity to develop resistance. An especially promising branch of antimicrobial peptides target Lipid II, the precursor of the bacterial peptidoglycan network. Read More

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http://dx.doi.org/10.1002/cbic.201800796DOI Listing
February 2019

Manipulating Active Structure and Function of Cationic Antimicrobial Peptide CM15 by the Polysulfonated Drug Suramin: A Step Closer to in vivo Complexity.

Chembiochem 2019 Feb 5. Epub 2019 Feb 5.

HUNGARY.

Antimicrobial peptides (AMPs) kill bacteria by targeting their membranes via various mechanisms involving peptide assembly often coupled with disorder-to-order structural transition. However, similar conformational changes were recently reported for several AMPs, where small organic molecules of both endogenous and exogenous origin induced folded peptide conformation. Thus, function of AMPs and natural host defense peptides can be significantly affected by the local complex molecular environment in vivo, nonetheless this area is hardly explored. Read More

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http://dx.doi.org/10.1002/cbic.201800801DOI Listing
February 2019

The binding mode of an ADP analog to a metallohydrolase mimics the likely transition state.

Chembiochem 2019 Feb 4. Epub 2019 Feb 4.

The University of Queensland, School of Chemistry & Molecular Biosciences, 68 Cooper Road, 4072, Brisbane, AUSTRALIA.

Purple acid phosphatases (PAPs) are members of the large family of metallohydrolases, a group of enzymes that perform a wide range of biological functions, while employing a highly conserved catalytic mechanism. PAPs are found in plants, animals and fungi, and in humans they play an important role in bone turnover and are thus of interest to develop treatments for osteoporosis. The majority of metallohydrolases use a metal-bound hydroxide to initiate catalysis, leading to the formation of a proposed five-coordinate oxyphosphorane species in the transition state. Read More

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http://dx.doi.org/10.1002/cbic.201900077DOI Listing
February 2019
1 Read

CRISPR-Cas-Mediated Chemical Control of Transcriptional Dynamics in Yeast.

Chembiochem 2019 Feb 1. Epub 2019 Feb 1.

University of Washington, Chemistry, 36 Bagley Hall, Department of Chemistry, University of Washington, 98195, Seattle, UNITED STATES.

Synthetic CRISPR-Cas transcription factors enable the construction of complex gene expression programs, and chemically-inducible systems allow precise control over the expression dynamics. To provide additional modes of regulatory control, we have constructed a chemically-inducible CRISPR activation (CRISPRa) system in yeast that is mediated by recruitment to MS2-functionalized guide RNAs. We use reporter gene assays to systematically map the dose-dependence, time-dependence, and reversibility of the system. Read More

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http://dx.doi.org/10.1002/cbic.201800823DOI Listing
February 2019

In-situ Configuration Study on Segmented DNA Origami Nanotubes.

Chembiochem 2019 Jan 31. Epub 2019 Jan 31.

Institute of Molecular Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, 160 Pujian Road, 200127, Shanghai, CHINA.

One-dimensional nanotubes are of considerable interest in materials and biochemical sciences. A particular desire is to create DNA nanotubes with user-defined structural features and biological relevance, which will facilitate the application of these nanotubes in the controlled release of drugs, templation of other materials into linear arrays and construction of artificial membrane channels. However, little is known about the structural information of assembled DNA nanotubes in solution. Read More

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http://dx.doi.org/10.1002/cbic.201800727DOI Listing
January 2019

KnowVolution of a fungal laccase toward alkaline pH.

Chembiochem 2019 Jan 31. Epub 2019 Jan 31.

RWTH Aachen University, Lehrstuhl fuer Biotechnologie, Worringer Weg 3, 52074, Aachen, GERMANY.

To date, commercial laccase preparations are used in food, textile, and paper and pulp industry (mild pH). Laccases are attractive in synthesis of dye molecules or oxidative lignin treatment, which take place at high pH (pH ≥ 8.0). Read More

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http://dx.doi.org/10.1002/cbic.201800807DOI Listing
January 2019

Optimal substrate trapping mutants to discover substrates of HDAC1.

Chembiochem 2019 Jan 30. Epub 2019 Jan 30.

Wayne State University, Department of Chemistry, 5101 Cass Avenue, 48202, Detroit, UNITED STATES.

Histone deacetylase 1 (HDAC1) regulates transcription by deacetylating histones. In addition to histones, several non-histone proteins are HDAC1 substrates, which verified a role for HDAC1 beyond epigenetics. Unfortunately, identification of non-histone substrates has been largely serendipitous, making full characterization of HDAC1 functions difficult. Read More

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http://dx.doi.org/10.1002/cbic.201800797DOI Listing
January 2019
1 Read

Artificial Cellulosome Complex from the Self-Assembly of NTANi Functionalized Polymeric Micelles and Cellulases.

Chembiochem 2019 Jan 29. Epub 2019 Jan 29.

Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208, USA, UNITED STATES.

Polymer-protein core-shell nanoparticles have been explored for enzyme immobilization. This work reports the development of functional polymeric micelles for immobilizing 6×His-tagged cellulases with controlled spatial orientation of enzymes, resulting in "artificial cellulosomes" for effective cellulose hydrolysis. Poly(styrene)-b-poly(styrene-alt-maleic anhydride) (PS-b-PSMA) was prepared through one-pot reversible addition-fragmentation chain-transfer (RAFT) polymerization and modified by nitrilotriacetic acid (NTA) to afford an amphiphilic block copolymer. Read More

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http://dx.doi.org/10.1002/cbic.201900061DOI Listing
January 2019
1 Read
3.088 Impact Factor

Dissociative Bioorthogonal Reactions.

Chembiochem 2019 Jan 29. Epub 2019 Jan 29.

University of Utah, Department of Medicinal Chemistry, 30 S 2000 E, SKH 1926, 84112, Salt Lake City, UNITED STATES.

Bioorthogonal reactions that proceed readily at physiological conditions without interference from biomolecules have found widespread application in the life sciences. Complementary to bioorthogonal reactions that ligate two molecules, there is an increasing interest in reactions that release a molecule or cleave a linker. Such dissociative bioorthogonal reactions have a broad spectrum of uses, for example in controlling biomacromolecule activity, in drug delivery, and in diagnostic assays. Read More

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http://dx.doi.org/10.1002/cbic.201800810DOI Listing
January 2019

Evolution of C-terminal modification tolerance in full-length and split T7 RNA Polymerase biosensors.

Chembiochem 2019 Jan 29. Epub 2019 Jan 29.

UChicago, chem, 929 e 57th st, 60637, CHicago, UNITED STATES.

T7 RNA polymerase (RNAP) is a powerful protein scaffold for the construction of synthetic biology tools and biosensors. However, both T7 RNAP and its split variants are intolerant to C-terminal modifications or fusions, placing a key limitation on its engineering and deployment. Here, we use rapid continuous evolution approaches to evolve both full-length and split T7 RNAP variants that tolerate modified C-termini and fusions, including fusions to entire other proteins. Read More

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http://dx.doi.org/10.1002/cbic.201800707DOI Listing
January 2019

Targeted Rediscovery and Biosynthesis of the Farnesyl-Transferase Inhibitor Pepticinnamin E.

Chembiochem 2019 Jan 29. Epub 2019 Jan 29.

University of North Carolina at Chapel Hill, Chemistry, 125 South Rd., CB #3290, 27599, Chapel Hill, UNITED STATES.

The natural product pepticinnamin E potently inhibits protein farnesyl transferases and has potential applications in treating cancer and malaria. Pepticinnamin E contains a rare N-terminal cinnamoyl moiety and several nonproteinogenic amino acids including an unusual 2-chloro-4-O-methyl-3,4-dihydroxy-l-phenylalanine. The biosynthesis of pepticinnamin E has remained uncharacterized because its original producing strain is unavailable. Read More

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http://dx.doi.org/10.1002/cbic.201900025DOI Listing
January 2019

Orthogonally Stimulated Assembly/Disassembly of Depsi-peptides by Rational Chemical Design.

Chembiochem 2019 Jan 28. Epub 2019 Jan 28.

Max Planck Institute for Polymer Research, Synthesis of Macromolecules, Ackermannweg 10, 55128, Mainz, GERMANY.

The control over assembly and disassembly of cross-β-sheet forming peptides is one of the predominant challenges for this class of supramolecular material. Being a continuously propagating material, every atomic change can be exploited to bring about distinct responses from the architectural level. By rational chemical design, we report herein that serine and methionine can both be used as orthogonal chemical triggers to signal assembly/disassembly via their corresponding stimuli. Read More

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http://dx.doi.org/10.1002/cbic.201800781DOI Listing
January 2019

Organic semiconductors for photothermal therapy and photoacoustic imaging.

Chembiochem 2019 Jan 28. Epub 2019 Jan 28.

CHINA.

In recent years, semiconducting polymer nanoparticles (SPNs) have attracted considerable attention because of their outstanding characteristics such as higher light and thermal stability. It is widely used in the field of biomedicine such as photoacoustic (PA) imaging, photodynamic (PDT) and photothermal (PTT). Photoacoustic imaging, a novel imaging modality based on photoacoustic effect, shows great promise in biomedical applications. Read More

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http://doi.wiley.com/10.1002/cbic.201800818
Publisher Site
http://dx.doi.org/10.1002/cbic.201800818DOI Listing
January 2019
3 Reads

A Branched Tripeptide with an Anion-Binding Motif as a Novel Delivery Carrier for Efficient Gene Transfection.

Chembiochem 2019 Jan 25. Epub 2019 Jan 25.

Universität Duisburg-Essen, Institut für Organische Chemie Fachbereich Chemie, Universitätsstraße 5, 45141, Essen, GERMANY.

Recently, branched and dendrimeric cationic peptides have shown increasing transfection efficiency compared to linear peptides owing to their superior capacity for DNA condensation. Herein, we design and synthesize two analogously guanidinocarbonylpyrrole (GCP)-substituted branched cationic tripeptides, which provide extremely strong electrostatic attraction with plasmid DNA. Both ligands 1 and 2 can bind to plasmid DNA and form condensed complexes owing to the branched structure and high positive charges, as demonstrated by isothermal titration calorimetry (ITC), Zeta-potential and atomic-force microscopy (AFM). Read More

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http://dx.doi.org/10.1002/cbic.201800728DOI Listing
January 2019
3.088 Impact Factor

Biosenors and Bioimaging.

Authors:
Kanyi Pu

Chembiochem 2019 Feb 25;20(4):420-421. Epub 2019 Jan 25.

Nanyang Technological University, School of Chemical and Biomedical Engieering, 70 Nanyang Drive, 637457, Singapore, Singapore.

Biosensors and molecular probes enable the study of biological and pathological processes in living systems at the molecular level, thereby playing an indispensable role in linking chemistry and biology to medicine. In this special issue, experts report the latest advances in the design and application of molecular probes for sensing and imaging both in vitro and in vivo. Read More

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http://dx.doi.org/10.1002/cbic.201900021DOI Listing
February 2019

Tropolone-conjugated DNA: Fluorescence Enhancement in the Duplex.

Chembiochem 2019 Jan 24. Epub 2019 Jan 24.

National Institute of Science Education and Research, School of Chemical Sciences, Jatni campus, 752050, Bhubaneswar, INDIA.

Tropolone is non-benzenoid bioactive natural chromophore comprising pH dependent fluorescent character and extraordinarily metal binding affinity especially with transition metal ions Cu2+/Zn2+/Ni2+. This report describes the syntheses and biophysical studies of new tropolonyl thymidine (tr-T) nucleoside and tropolone conjugated DNA oligonucleotides which form B-form DNA duplex structure with complementary DNA strand. Though their duplex structures are less stable as compare to the control. Read More

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http://dx.doi.org/10.1002/cbic.201800822DOI Listing
January 2019

Transesterification of a Tertiary Alcohol by Engineered Candida Antarctica Lipase A.

Chembiochem 2019 Jan 24. Epub 2019 Jan 24.

SWEDEN.

Tertiary alcohols are known to be challenging substrates for applications in asymmetric synthesis, due to their complexity and steric hinderance. The occurrence of tertiary alcohols and their esters in Nature indicates the presence of natural biocatalytic synthetic routes for their preparation. Lipase A from Candida antarctica (CalA) is a hydrolase enzyme, which has previously been shown to catalyze transesterification of racemic 2-phenylbut-3-yn-2-ol at a low reaction rate. Read More

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http://dx.doi.org/10.1002/cbic.201800792DOI Listing
January 2019

Recent developments in metal catalyzed bio-orthogonal reactions for biomolecule tagging.

Chembiochem 2019 Jan 24. Epub 2019 Jan 24.

Korea Institute of Science and Technology, Molecular Recognition Research Center, 39-1 Hawolgok-Dong, Seongbuk-Gu, 136-791, Seoul, KOREA, REPUBLIC OF.

With the rapid advances in single molecule and live cell imaging studies to investigate biological problems, the role of chemical probes to monitor reactions in a live cell has considerably increased. However, selective labeling of a target protein or a specific residue is highly challenging due to the high complexity of the biological system. In particular, biological macromolecules (such as proteins, DNA, or RNA) share many functional groups that potentially cross-react with exogenous chemical probes. Read More

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http://dx.doi.org/10.1002/cbic.201900052DOI Listing
January 2019
3.088 Impact Factor

Modulating Protein-Protein Interactions with Visible-Light Responsive Peptide Backbone Photoswitches.

Chembiochem 2019 Jan 24. Epub 2019 Jan 24.

Philipps-Universität Marburg, Chemistry, Hans-Meerwein-Strasse 4, 35032, Marburg , GERMANY.

Life relies on a myriad of carefully orchestrated processes, in which proteins and their direct interplay ultimately determine cellular function and disease. Modulation of these complex cross-talks has recently attracted attention, even as a novel therapeutic strategy. Here, we describe the synthesis and characterization of two visiblelight responsive peptide backbone photoswitches based on azobenzene derivatives to exert optical control over protein-protein interactions (PPI). Read More

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http://dx.doi.org/10.1002/cbic.201800737DOI Listing
January 2019
1 Read

Glycosylated Cell Penetrating Peptides, GCPPs.

Chembiochem 2019 Jan 23. Epub 2019 Jan 23.

Universidad de Santiago de Compostela, Departamento de Química Orgánica, c/ Jenaro de la Fuente s/n, 15782, Santiago de Compostela, SPAIN.

The cell membrane regulates the exchange of molecules and information with the external environment. However, this control barrier hinders the delivery of exogenous bioactive molecules that can be applied to correct cellular malfunctions. Therefore, the traffic of macromolecules across the cell membrane represents a great challenge for the development of the next generation of therapies and diagnostic methods. Read More

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http://dx.doi.org/10.1002/cbic.201800720DOI Listing
January 2019
4 Reads

Synthesis and application of methyl N,O-hydroxylamine muramyl peptides.

Chembiochem 2019 Jan 22. Epub 2019 Jan 22.

University of Delaware, Chemistry and Biochemistry, 134 The Green, Brown Labs, 19711, Newark, UNITED STATES.

The innate immune system's interaction with bacterial cells plays a pivotal role in a variety of human diseases. Carbohydrate units derived from a component of bacterial cell wall, peptidoglycan (PG), are known to stimulate an immune response. Nonetheless, access to modified late stage peptidoglycan intermediates is limited due to their synthetic complexity. Read More

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http://dx.doi.org/10.1002/cbic.201800731DOI Listing
January 2019

Hemoprotein-catalyzed cyclopropanation en route to the chiral cyclopropanol fragment of grazoprevir.

Chembiochem 2019 Jan 22. Epub 2019 Jan 22.

Merck and Co Inc, Enabling Technologies, 126 E. Lincoln Ave, 07065, Rahway, UNITED STATES.

Reactions that were once the exclusive province of synthetic catalysts can increasingly be addressed using biocatalysis. Through discovery of non-natural enzyme reactions, biochemists have significantly expanded the reach of enzymatic catalysis to include carbene transfer chemistries including olefin cyclopropanation. Here we describe hemoprotein cyclopropanation catalysts derived from thermophilic bacterial globins that react with diazoacetone and an unactivated olefin substrate to furnish a cyclopropyl ketone, a previously unreported reaction for enzyme catalysts. Read More

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http://dx.doi.org/10.1002/cbic.201800652DOI Listing
January 2019
3.088 Impact Factor

Structure-Based Specific Detection and Inhibition of Monoamine Oxidases and Their Applications in Central Nervous System Diseases.

Chembiochem 2019 Jan 21. Epub 2019 Jan 21.

CHINA.

Monoamine oxidases (MAOs) are the enzymes that catalyze the oxidation of monoamines such as dopamine, norepinephrine, serotonin, which serve as the key neurotransmitters in the central nervous system (CNS). MAOs play important roles in maintaining the homeostasis of monoamines and aberrant expression or activation of MAOs underlies the pathogenesis of monoamine neurotransmitter disorders including neuropsychiatric and neurodegenerative diseases. Obviously, detecting and inhibiting activities of MAOs is of great value for the diagnosis and therapeutics of these diseases. Read More

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http://dx.doi.org/10.1002/cbic.201800813DOI Listing
January 2019
2 Reads

Synthetic and crystallographic insight into exploiting sp2-hybridization in the development of α-L-fucosidase inhibitors.

Chembiochem 2019 Jan 21. Epub 2019 Jan 21.

University of Western Australia, Chemistry M313, 35 Strirling Highway, School of Chemistry and Biochemistry, 6009, Crawley, AUSTRALIA.

The sugar fucose plays a myriad of roles in biological recognition. Enzymes hydrolyzing fucose from glycoconjugates, α-L-fucosidases, are important targets for inhibitor and probe development. Here we describe the synthesis and evaluation of novel α-L-fucosidase inhibitors, with X-ray crystallographic analysis using an α-L-fucosidase from Bacteroides thetaiotamicron helping to lay a foundation for future development of inhibitors for this important enzyme class. Read More

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http://dx.doi.org/10.1002/cbic.201800710DOI Listing
January 2019
1 Read

Amplified Expansion Stimulated Emission Depletion Microscopy.

Chembiochem 2019 Jan 17. Epub 2019 Jan 17.

Korea University, Chemistry, KOREA, REPUBLIC OF.

Expansion microscopy (ExM) enhances spatial resolution using a swellable polymer that expands the sample volume by a factor of ~4 in one dimension and factor of ~20 in volume. Combining ExM with stimulated emission depletion (STED) microscopy, referred to as ExSTED, increases the resolution to up to 10 nm. However, photobleaching is a critical issue in ExSTED because sample expansion lowers fluorophore density and high-resolution STED requires high depletion intensity. Read More

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http://dx.doi.org/10.1002/cbic.201800775DOI Listing
January 2019
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Light-wavelength-based Quantitative Control of Dihydrofolate Reductase Activity Using Photochromic Isostere of Inhibitor.

Chembiochem 2019 Jan 17. Epub 2019 Jan 17.

JAPAN.

Photopharmacology has attracted research attention as a new tool to achieve the optical control of biomolecules following the methods of caged compounds and optogenetics. We have developed an efficient photopharmacological inhibitor, azoMTX, for Escherichia coli dihydrofolate reductase (eDHFR) by replacing some atoms of the original ligand, methotrexate, to obtain the photoisomerization property. This fine molecular design enabled the quick structural conversion between the active 'bent' Z-isomer and the inactive 'extended' E-isomer of azoMTX, and this property afforded quantitative control of the enzyme activity, depending on the wavelength of irradiated light. Read More

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http://dx.doi.org/10.1002/cbic.201800816DOI Listing
January 2019
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Elusive Dehydroalanine Derivatives with Enhanced Reactivity.

Chembiochem 2019 Jan 16. Epub 2019 Jan 16.

Universidad de la Rioja, Departamento de Química, Madre de Dios, 53, 26006, Logroño, SPAIN.

For the first time, a simple methodology for the chemical synthesis and utilization of highly reactive 4-methylen-oxazol-5(4H)-ones from serine is presented. These dehydroalanine derivatives, which resemble the natural 4-methylideneimidazole-5-one (MIO) cofactor present in lyases and aminomutases, undergo rapid reaction with carbon nucleophiles such as silyl enol ethers, and cycloaddition reactions with diazo compounds and reactive dienes under very mild conditions and in the absence of metal catalysts and ring-strain activation, offering potential for bioconjugation. Read More

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http://dx.doi.org/10.1002/cbic.201800758DOI Listing
January 2019
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Bimodal detection of proteins by 129Xe NMR and fluorescence spectroscopy.

Chembiochem 2019 Jan 16. Epub 2019 Jan 16.

Laboratoire de Chimie Physique, UMR CNRS 8000, Bat 349, 914005, Orsay, FRANCE.

The full understanding of biological phenomena involves sensitive and non -invasive detection. Here we report the optimization of a probe for intracellular proteins that combines the advantages of fluorescence and hyperpolarized 129Xe NMR detection. The fluorescence detection part is composed of six residues containing a tetracysteine tag (-CCXXCC-) genetically incorporated into the protein of interest and of a small organic molecule, CrAsH. Read More

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http://doi.wiley.com/10.1002/cbic.201800802
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http://dx.doi.org/10.1002/cbic.201800802DOI Listing
January 2019
5 Reads
3.088 Impact Factor

Ribosomal peptides and small proteins on the rise.

Chembiochem 2019 Jan 16. Epub 2019 Jan 16.

TU Munich Chair of Biochemistry, Chemistry, Lichtenbergstr. 4, 85747, Garching, GERMANY.

Genetically encoded and ribosomally synthesised small proteins and peptides act as important regulators in fundamental cellular processes, including gene expression, development, signalling and metabolism. Moreover, they also play a crucial role in the eukaryotic and prokaryotic defence against microorganisms and are extremely diverse in size and structure, and are often subject to extensive posttranslational modification. Recent technological advances now allow the analysis of the whole cellular transcriptome and proteome, revealing the presence of hundreds, long overlooked, alternative and short open reading frames (ORFs) in mRNA and supposedly non-coding RNAs. Read More

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http://doi.wiley.com/10.1002/cbic.201800715
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http://dx.doi.org/10.1002/cbic.201800715DOI Listing
January 2019
5 Reads

Identification of Potent Caspase-8 Inhibitors from a Library of Fluorescent Natural Products Screened by an AIEgen-based Light-up Probe.

Chembiochem 2019 Jan 16. Epub 2019 Jan 16.

Chinese Academy of Medical Sciences and Peking Union Medical College, Institute of Meteria Medica, Nan Wei Lu Jia Er Hao, 100050, Beijing, CHINA.

Fluorescent natural products are a rich source of drugs and chemical probes. But their inborn fluorescence may interfere with the fluorescence-based screening assays. Caspase-8 is a key player in apoptosis. Read More

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http://doi.wiley.com/10.1002/cbic.201800723
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http://dx.doi.org/10.1002/cbic.201800723DOI Listing
January 2019
4 Reads

Biomimetic Carbohydrate Binding Agents (CBAs): binding affinities and biological activities.

Chembiochem 2019 Jan 15. Epub 2019 Jan 15.

Universita degli Studi di Firenze, Chemistry, Via della Lastruccia, 13, 50019, Sesto Fiorentino, ITALY.

Mimicking Nature in carbohydrate recognition, that is using non-covalent interactions exclusively, is a hot topic that has attracted the interest of many scientists in the last thirty years. Carbohydrates are challenging ligands of high biological relevance, playing a central role in several physiological and pathological processes. Carbohydrate binding agents (CBAs) of proteic nature, such as lectins, has been extensively used in glycobiology to target carbohydrates, but intrinsic drawbacks given by their proteic nature limit their therapeutic development. Read More

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http://dx.doi.org/10.1002/cbic.201800742DOI Listing
January 2019
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Identification and quantification of (t)RNA modifications in Pseudomonas aeruginosa by liquid chromatography-tandem mass spectrometry.

Chembiochem 2019 Jan 15. Epub 2019 Jan 15.

GERMANY.

Transfer RNA (tRNA) modifications impact the structure and function of tRNAs thus affecting the efficiency and fidelity of translation. In the opportunistic pathogen Pseudomonas aeruginosa translational regulation plays an important but less defined role in the adaptation to changing environments. In this study, we explored tRNA modifications in P. Read More

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http://dx.doi.org/10.1002/cbic.201800741DOI Listing
January 2019
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Direct Imaging of Protein-Specific Methylation in Mammalian Cells.

Chembiochem 2019 Jan 15. Epub 2019 Jan 15.

Universitat Konstanz, Chemie, 78457 Konstanz, 78457, Konstanz, GERMANY.

The abundant post-translational modification methylation alters a protein's function, stability, and/or localization. Its malfunctions are associated with severe diseases. To unravel protein methylation sites and their biological functions, chemical methylation reporters have been developed. Read More

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http://dx.doi.org/10.1002/cbic.201800787DOI Listing
January 2019
1 Read