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Search for "proteins" in Full Text gives 518 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Tools for generating and analyzing glycan microarray data
Beilstein J. Org. Chem. 2020, 16, 2260–2271, doi:10.3762/bjoc.16.187
- structural informatics tools. Keywords: data analysis; glycan binding; glycan microarray; glycomics; informatics; Introduction Glycans represent a major type of biomolecule in all living things, along with DNA, RNA, lipids and proteins [1]. In mammals, glycans commonly occur as post-translational
- modifications of proteins (glycoproteins), but they are also linked to lipids (glycolipids) and occur as free molecules. Such glycomolecules have vital roles in a wide range of physiological functions and also participate in many pathologic conditions [2]. Some classic examples of important glycans include the
- , and could possibly promote cancer [4], and the O-glycan of PSGL-1 which is recognized by P- and L-selectin, which is critical for leukocyte recruitment [5][6]. Other roles of glycans (including glycosaminoglycans/proteoglycans) and glycan binding proteins (GBPs) (including lectins and antibodies) in
GlypNirO: An automated workflow for quantitative N- and O-linked glycoproteomic data analysis
Beilstein J. Org. Chem. 2020, 16, 2127–2135, doi:10.3762/bjoc.16.180
- proteomic sample preparation and protease digestion, coupled with depletion of abundant proteins or enrichment of glycopeptides to enable their measurement. There have also been several advances in glycopeptide quantification strategies including chemical labelling, label-free and data-independent
- ]. Our analysis revealed differences in occupancy and glycan compositions of several proteins as potential HCC tumor biomarkers. Results and Discussion GlypNirO Byonic is powerful software that allows identification of glycopeptides and peptides from complex glyco/proteomic LC–MS/MS datasets but does not
- depleted of six abundant proteins from liver cancer (hepatocellular carcinoma (HCC)) patients and healthy controls. We identified glycopeptides and peptides in the datafiles from these samples using Byonic, searching separately for O- and N-glycopeptides (Supporting Information File 1, Tables S1–S24), and
How and why plants and human N-glycans are different: Insight from molecular dynamics into the “glycoblocks” architecture of complex carbohydrates
Beilstein J. Org. Chem. 2020, 16, 2046–2056, doi:10.3762/bjoc.16.171
- Carl A. Fogarty Aoife M. Harbison Amy R. Dugdale Elisa Fadda Department of Chemistry and Hamilton Institute, Maynooth University, Maynooth, Kildare, Ireland 10.3762/bjoc.16.171 Abstract The N-glycosylation is one of the most abundant and diverse post-translational modifications of proteins
- implicated in the cell’s interactions with its environment, facilitating communication and infection [1][2]. These processes are often initiated by molecular recognition involving carbohydrate-binding proteins (lectins) or by glycan–glycan interactions [1][3][4][5], all events that hinge on specific
- the links between glycans’ sequence and the 3D structure. This direct relationship is a well-recognized and broadly accepted concept in proteins’ structural biology, according to which the amino acid sequence dictates the functional 3D fold and its stability. However, the same notion is not generally
Naphthalene diimide–amino acid conjugates as novel fluorimetric and CD probes for differentiation between ds-DNA and ds-RNA
Beilstein J. Org. Chem. 2020, 16, 2032–2045, doi:10.3762/bjoc.16.170
- ; Introduction The interplay of non-covalent interactions between nucleic acids and proteins or peptides is the basis of life and is also often used for the design of artificial small molecules, aiming for sensing or control of biorelevant processes. Many naturally occurring bioactive molecules contain a short
- several decades, consequently becoming increasingly complex [5][6][7]. This includes examples incorporating several types of non-covalent interaction with DNA/RNA (intercalation, groove binding, positive–negative charge interaction [5][8]) in one molecule or even modified biomacromolecules (e.g., proteins
Automated high-content imaging for cellular uptake, from the Schmuck cation to the latest cyclic oligochalcogenides
Beilstein J. Org. Chem. 2020, 16, 2007–2016, doi:10.3762/bjoc.16.167
- challenge is most pronounced with large substrates, such as proteins, oligonucleotides, or nanoparticles, due to the permeability barriers formed by the lipophilic core of the cell membrane [18][19]. In recent decades, the use of arginine-rich cell-penetrating peptides (CPPs) as carriers has emerged as an
- generally decreases with the size [18], this similarity is particularly impressive, considering that the COC carrying a 52 kDa protein is compared to a small undecapeptide. The compatibility of the assay with other fusion proteins and more adverse conditions, such as transient transfection, has never been
Selective preparation of tetrasubstituted fluoroalkenes by fluorine-directed oxetane ring-opening reactions
Beilstein J. Org. Chem. 2020, 16, 1936–1946, doi:10.3762/bjoc.16.160
- hydrogen-bond accepting capacity with proteins or enzymes would be restored [14]. The synthesis of fluoroalkene precursors of modified acyclonucleosides (VIII) has been explored by Choi, and more recently by us [15][16][17]. Nevertheless, it was reported that no antiviral activity for compounds of series
Polarity effects in 4-fluoro- and 4-(trifluoromethyl)prolines
Beilstein J. Org. Chem. 2020, 16, 1837–1852, doi:10.3762/bjoc.16.151
- Vladimir Kubyshkin University of Manitoba, Dysart Rd. 144, Winnipeg, R3T 2N2, Canada 10.3762/bjoc.16.151 Abstract Fluorine-containing analogues of proline are valuable tools in engineering and NMR spectroscopic studies of peptides and proteins. Their use relies on the fundamental understanding of
- complex structures: peptides and proteins. Results and Discussion Model compounds The study was originally set up following an assumption that a peptide containing a proline analogue would form a system of three dipoles. The peptide bond itself creates a strong dipole, with a direction that roughly aligns
- protein chemistry. The peptide bond can exist in two discrete states, commonly designated as trans- and cis-rotamers (ω = 180 and 0°, respectively). The cis-peptide bond is very rare in natural proteins [79], except for the cases when it precedes a proline residue. The secondary amino group of proline
Nonenzymatic synthesis of anomerically pure, mannosyl-based molecular probes for scramblase identification studies
Beilstein J. Org. Chem. 2020, 16, 1732–1739, doi:10.3762/bjoc.16.145
- Bern, Switzerland Department of Biochemistry, Weill Cornell Medical College, 1300 York Avenue, 10065 New York, United States of America 10.3762/bjoc.16.145 Abstract The chemical synthesis of molecular probes to identify and study membrane proteins involved in the biological pathway of protein
- the use of photoreactive, clickable MPD mimics. As such, an attempt already showed great promise in a previous report by Rush et al. from 2015 [10]. Similarly, we envisioned that these analogs could be used to capture MPD-recognizing proteins, including the scramblase, from a crude mixture of ER
- membrane proteins [11][12]. The captured proteins would be subsequently identified by mass spectrometry, and their function in MPD scrambling validated by biochemical and genetic approaches. A suitable molecular probe and mimic of MPD (Figure 1) can be subdivided into three essential components: a β-ᴅ
Models of necessity
Beilstein J. Org. Chem. 2020, 16, 1649–1661, doi:10.3762/bjoc.16.137
- -atomic representation [73]. These force fields have attained a remarkable level of accuracy for proteins, so that force-field based simulations have become predictive in many fields of biology, medicinal chemistry and biophysics [74]. Models, approximations and paradigms Despite the many advances made
- molecular aggregation via weak interactions. Paradoxically, exactly such interactions between drug molecules and proteins form much of the basis of classical cheminformatics. These are, however, very specific in nature and have generally been defined in detail for, for instance, scoring functions. Current
A dynamic combinatorial library for biomimetic recognition of dipeptides in water
Beilstein J. Org. Chem. 2020, 16, 1588–1595, doi:10.3762/bjoc.16.131
- the parallel dimer of CHC (p(CHC)2), which binds two molecules of the neurotransmitter N-acetylneuraminic acid (NANA) in a cooperative fashion (K1 = 143, K2 = 5.1 × 103 M−1). Recently we rationalized that since our peptide building blocks consist of the same binding motifs as binding proteins (amines
Heterogeneous photocatalysis in flow chemical reactors
Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125
Synthesis of new fluorescent molecules having an aggregation-induced emission property derived from 4-fluoroisoxazoles
Beilstein J. Org. Chem. 2020, 16, 1411–1417, doi:10.3762/bjoc.16.117
- be visualized using fluorescent probes, the use of AIE fluorescent probes is being investigated as a tool for analyzing the causal relationship between prion diseases and prion proteins. The importance of fluorinated heterocyclic derivatives in the pharmaceutical and agrochemical industries continues
Photocatalytic trifluoromethoxylation of arenes and heteroarenes in continuous-flow
Beilstein J. Org. Chem. 2020, 16, 1305–1312, doi:10.3762/bjoc.16.111
- (Scheme 1A). This property might be responsible for stronger binding affinities of trifluoromethoxylated compounds with the active sites in enzymes, proteins, or other biomolecules [8][9]. Several procedures for the synthesis of trifluoromethyl aryl ethers were reported from the mid-1900s, mostly based on
Anthelmintic drug discovery: target identification, screening methods and the role of open science
Beilstein J. Org. Chem. 2020, 16, 1203–1224, doi:10.3762/bjoc.16.105
- basis for finding compounds that are anthelmintic in vivo but do not cause paralysis, perhaps involving aspects of the interaction with the host, interfering with the secretion of proteins, or other ways of damaging the worm [146]. They are also useful for understanding in more detail the mechanism of
A smart deoxyribozyme-based fluorescent sensor for in vitro detection of androgen receptor mRNA
Beilstein J. Org. Chem. 2020, 16, 1135–1141, doi:10.3762/bjoc.16.100
- . Petersburg, 197101, Russian Federation 10.3762/bjoc.16.100 Abstract Nowadays a variety of biosensors are widely used in different fields, including biomedical diagnostics and self-testing. Nucleic acid-based biosensors are typically applied to detect another nucleic acid, proteins, ions, and several other
- different levels, including DNA, RNA, proteins, and small molecule metabolites. Today, along with other methods in clinical diagnosis biosensors are ubiquitously used in the biomedical field. The first prototype of a biosensor was invented by Leland Clark and Champ Lyons in 1962 as an amperometric Clark
- . Reproducibility and linearity are also very important as well as costs and ease of manufacturing each component of the biosensor. Unlike proteins or antibodies the nucleic acid-based biosensors (NAs) can be easily commercially synthesized, they are smaller, more stable, and can be repeatedly used without losing
Synthesis of esters of diaminotruxillic bis-amino acids by Pd-mediated photocycloaddition of analogs of the Kaede protein chromophore
Beilstein J. Org. Chem. 2020, 16, 1111–1123, doi:10.3762/bjoc.16.98
- in the last few years due to the discovery that truxillic acid derivatives are inhibitors of FABP (fatty acid binding proteins), which are responsible for the cellular reuptake of anandamide, an endocannabinoid neurotransmitter, and that they can be involved in a very efficient treatment for chronic
Fluorinated phenylalanines: synthesis and pharmaceutical applications
Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91
- . Incorporation of fluorinated aromatic amino acids into proteins increases their catabolic stability especially in therapeutic proteins and peptide-based vaccines. This review seeks to summarize the different synthetic approaches in the literature to prepare ᴅ- or ʟ-fluorinated phenylalanines and their
- the properties of peptides and proteins [5][6][7], influencing aspects such as protein folding, protein–protein interactions, ribosomal translation, lipophilicity, acidity/basicity, optimal pH, stability, thermal stability, and therapeutic properties [8][9][10]. This extends to metabolic properties of
- membrane permeability and reactivity [11][12][13][14]. The effect of peptide structure and stability has been found to depend on the position and number of fluorine atoms within the amino acid chains [15][16][17]. Incorporation of fluorinated aromatic amino acids into proteins can increase their shelf life
Synthesis of new asparagine-based glycopeptides for future scanning tunneling microscopy investigations
Beilstein J. Org. Chem. 2020, 16, 888–894, doi:10.3762/bjoc.16.80
- Glycopeptides are generally found on virtually every eukaryotic and prokaryotic cell surface. So far, the study of glycopeptide interactions with other proteins gave some insight into important biological functions, for instance, intracellular communication, cell–cell recognition, immune response, and
- pathogenesis [1][2][3][4]. Glycosylation is also considered to be one of the most important post-translational modification (PTM) since more than half of all human proteins are glycopeptides or glycoproteins [5]. Therefore, understanding how glycopeptides interact on an intra- and intermolecular level is
Design and synthesis of diazine-based panobinostat analogues for HDAC8 inhibition
Beilstein J. Org. Chem. 2020, 16, 628–637, doi:10.3762/bjoc.16.59
- involve acetylation/deacetylation of histone proteins by histone deacetylases (HDACs) [1]. HDACs belong to an important family of enzymes consisting of 18 isozymes. They control protein acetylation, which is a change that occurs after translation. In addition, they regulate gene transcription, cell
- differentiation, cell cycle progression and apoptosis by targeting both histone and non-histone proteins. The balance between acetylation and deacetylation is pivotal for typical cell function. Abnormal or increased HDAC expression has been reported in several human tumors and cancer cell lines [2]. As such, the
Opening up connectivity between documents, structures and bioactivity
Beilstein J. Org. Chem. 2020, 16, 596–606, doi:10.3762/bjoc.16.54
- . Although their expert-curated numbers are lower (i.e., ≈2 million compounds against ≈3700 human proteins), these open sources have the great advantage of being merged within PubChem. Parallel efforts have focused on the extraction of document-to-compound (D-C-only) connectivity. In the absence of molecular
- -R indicates C to be a potent inhibitor of P). Compounds: a full range of cheminformatic analysis including 2D or 3D clustering, property prediction and chemical ontology assignments. Proteins: a full range of bioinformatic analysis including gene ontology (GO) assignments, pathway annotation
- 4 are noteworthy and persist despite the ChEMBL/BindingDB selective mirroring. As for PMID coverage it would be useful to know which types of selectivity were responsible for this divergence in connectivity. For BindingDB some unique proteins are likely to be patent-only but exploring further causes
Convenient synthesis of the pentasaccharide repeating unit corresponding to the cell wall O-antigen of Escherichia albertii O4
Beilstein J. Org. Chem. 2020, 16, 106–110, doi:10.3762/bjoc.16.12
- cell wall polysaccharides with suitable proteins, which include vaccines against Haemophilia influenza type b (Hib) [12][13], meningitis [14], pneumococcal infections [15][16] and enteric diseases such as cholera [17], diarrhea [18] and urinary tract infections [19]. Despite the possibility of
Light-controllable dithienylethene-modified cyclic peptides: photoswitching the in vivo toxicity in zebrafish embryos
Beilstein J. Org. Chem. 2020, 16, 39–49, doi:10.3762/bjoc.16.6
- differences of erythrocytes compared to other somatic cells. Although easily measured, hemolytic activity gives only a rough estimate of toxicity for peptide therapeutics. Erythrocytes are terminally differentiated non-adherent organelle-free cells, densely packed with oxygen-carrying proteins; their
Synthesis and characterization of bis(4-amino-2-bromo-6-methoxy)azobenzene derivatives
Beilstein J. Org. Chem. 2019, 15, 3000–3008, doi:10.3762/bjoc.15.296
- . While many classes of photoswitches are known [1][2], few of these are easily adaptable to controlling targets, such as proteins [3], while simultaneously exhibiting robust photochemistry in the red or near-infrared (NIR) regions of the spectrum [4][5][6][7]. Azonium ions – protonated forms of
Pigmentosins from Gibellula sp. as antibiofilm agents and a new glycosylated asperfuran from Cordyceps javanica
Beilstein J. Org. Chem. 2019, 15, 2968–2981, doi:10.3762/bjoc.15.293
- , in particular orthopedic implant-related infections, since implants coated with proteins facilitate bacterial attachment and biofilm development [1]. In general, bacteria are known to employ different strategies to cope with the presence of antibiotics, of which a biofilm, an aggregate of
Chemical synthesis of tripeptide thioesters for the biotechnological incorporation into the myxobacterial secondary metabolite argyrin via mutasynthesis
Beilstein J. Org. Chem. 2019, 15, 2922–2929, doi:10.3762/bjoc.15.286
- peptide biosynthesis has previously been successfully performed using cell lysate, e.g., in case of gramicidin [24], or with purified proteins, e.g., in case of myxochelin [25] and tilivalline [26]. To evaluate if in vitro formation of argyrin is indeed possible, the reaction buffer was incubated with the
- cell lysate mixture of M. xanthus DK1622 mutants expressing the Arg2-Arg5 argyrin biosynthetic proteins. To ensure that no argyrin is present in the lysate prior to the incubation, a lysate mixture of two different mutants harboring arg2 and arg3-5 genes was used, respectively. Both of the mutants are
- incapable of argyrin production on their own, however, together they express all the necessary proteins. Despite significant efforts and evaluation of various incubation conditions, in vitro reconstitution of argyrins could never be achieved. The exact reason for this is unknown, however, it is very likely
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