Synthesis of New Substituted Lactones by "Click" Chemistry.
Photovoltaic Properties of New Cyanine-Naphthalimide Dyads Synthesized by 'Click' Chemistry.
M., Solid-phase synthesis of C-terminally modified peptides.
N2 - Lytic replication of the Kaposi's sarcoma-associated herpesvirus (KSHV) is essential for the maintenance of both the infected state and characteristic angiogenic phenotype of Kaposi's sarcoma and thus represents a desirable therapeutic target. During the peak of herpesvirus lytic replication, viral glycoproteins are mass produced in the endoplasmic reticulum (ER). Normally, this leads to ER stress which, through an unfolded protein response (UPR), triggers phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α), resulting in inhibition of protein synthesis to maintain ER and cellular homeostasis. However, in order to replicate, herpesviruses have acquired the ability to prevent eIF2α phosphorylation. Here we show that clinically achievable nontoxic doses of the glucose analog 2-deoxy-D-glucose (2-DG) stimulate ER stress, thereby shutting down eIF2α and inhibiting KSHV and murine herpesvirus 68 replication and KSHV reactivation from latency. Viral cascade genes that are involved in reactivation, including the master transactivator (RTA) gene, glycoprotein B, K8.1, and angiogenesis-regulating genes are markedly decreased with 2-DG treatment. Overall, our data suggest that activation of UPR by 2-DG elicits an early antiviral response via eIF2α inactivation, which impairs protein synthesis required to drive viral replication and oncogenesis. Thus, induction of ER stress by 2-DG provides a new antiherpesviral strategy that may be applicable to other viruses.
Protein glycosylation is one of the most prevalent posttranslational modifications in nature. Sugars attached on the surface of proteins play important roles in multiple physiological processes. However, the structural heterogeneity and complexity of oligosaccharide of glycoprotein had cast huge challenge on the synthesis of glycoproteins for studies on structure-function relationship that require structurally well-defined glycans. In the last decades, a number of approaches have been developed. Among them are chemoenzymatic syntheses of glycoproteins that showed extremely appealing prospect. In this chapter, we reviewed key technologies in chemoenzymatic synthesis of glycoproteins including native chemical ligation, glycoprotein remodeling, the potential of bacterial oligosaccharyltransferase in synthesis of glycoproteins, as well as two recent excellent progresses on chemoenzymatic synthesis of oligosaccharides followed by a fast high-throughput method for glycosyltransferases screening. The principles of these methods are described, and their applications are exemplified by several latest reports.
S., A new solvent system for efficient synthesis of 1,2,3-triazoles.
Various 68Ga-based imaging agents have already been tested in humans . The basic research and development of new 68Ga-based agents for targeted imaging of specific protein expression products, pre-targeted imaging as well as non-targeted imaging of pulmonary and myocardial perfusion and pulmonary ventilation is expanding steadily. Imaging of cell proliferation, hypoxia, glycolysis, angiogenes as well as inflammation and infection has also been considered . Radiochemistry plays a central role in the development and 68Ga in particular has demonstrated powerful potential. The prevalent area of 68Ga clinical applications in the nearest future will most probably be oncology. More research is required for the development of agents for cardiology. On the other hand, neurology will still be dominated by 11C- and 18F-based imaging agents since common requirements to specific binding, small size, lipophilicity and charge might be difficult to meet when using bulky radiometal-chelator complex to be attached to a small biologically active molecule.
The cDNAs for two glycoproteins, the 158-kDa submandibular glycoprotein (SGP158) and the 200-kDa parotid glycoprotein (PGP200), have been cloned from rat submandibular and parotid glands, respectively. Both cDNAs encode for identical proteins with repeating peptides -Asp-Gln-Gly-(Asn)-Gln-Thr-Gln-Pro-Arg-Pro-Pro-His-Pro-. A full-length cDNA encoding SGP158 was obtained using the strategy of anchor-PCR, and a full-length cDNA of PGP200 was prepared using RNA-PCR. Sequence analysis of the cDNAs revealed that SGP158 and PGP200 are identical proteins with 23 repeating peptides. Twentyone peptides contain potential N-glycosylation sites and these two glycoproteins differ only in their glycosylation patterns. Southern-blot analysis showed that a single-copy gene encodes both mRNAs. PGP200 is constitutively expressed, but the synthesis of SGP158 is totally dependent upon treatment of animals with the β-agonist isoproterenol. The first 106-nucleotide sequence of cDNAs for PGP200 and SGP158, which corresponds to the 5'prime;untranslated region and sequence encoding the signal peptide, is highly conserved when compared with proline-rich protein and glutamine-rich protein gene sequences. Based on the nucleotide sequences of exon I, a phylogenetic tree was constructed for 35 members of these multigene families. The tree fits with the generally recognized phylogeny of mammalian orders. We propose that exon I sequences of the proline-rich protein and glutamine-rich protein multigene families are relatively new and are possibly generated through exon shuffling during evolution.
H., His6 tag-assisted chemical protein synthesis.
Vadaie N and Jarvis DL (2004) Molecular cloning and functional characterization of a Lepidopteran insect beta4‐N‐acetylgalactosaminyltransferase with broad substrate specificity, a functional role in glycoprotein biosynthesis, and a potential functional role in glycolipid biosynthesis. Journal of Biological Chemistry 279: 33501–33518.
Inflammation plays an important role in the initiation of preterm birth, which remains the largest cause of neonatal deaths. In the present study, components of the protein synthesis machinery were significantly increased with labouring compared to non-labouring fetal membranes and myometrium, and blockade of protein synthesis significantly reduced inflammation in the myometrium. These results may provide further insight into the pathways involved in the initiation of preterm birth.
K., New methods for the synthesis of heterocyclic compounds.
O., Synthesis of new heterocyclic fatty compounds.
Gamblin DP, Scanlan EM and Davis BG (2009) Glycoprotein synthesis: an update. Chemical Reviews 109: 131–163.
A New Strategy for the Synthesis of Glycoproteins | Science
What is synthesis?
A New Strategy for the Synthesis of Glycoproteins
Modular Synthesis of ChiraClick Ligands: A Library of P-Chirogenic Phosphines.
A new strategy for the synthesis of glycoproteins
“For years, Jennifer Stanchfield has shown an avid interest in modern brain research and how it applies to what teachers and learners do together. Here she has brought together cognitive science, neuroscience, and education to achieve a synthesis that will intrigue many teachers.” —Sam Wang, Associate Professor of Neuroscience, Princeton University
A New Strategy for the Synthesis of Gloycoprotein
PET has become an established method for medical research and clinical routine diagnostics. Development and availability of new radiopharmaceuticals specific for particular diseases is one of the driving forces of the expansion of clinical nuclear medicine providing early personalized diagnosis and efficient therapy. The future development of 68Ga-radiopharmaceuticals must be put in the context of several aspects such as role of PET in nuclear medicine, unmet medical needs, identification of new biomarkers, targets and corresponding ligands, production and availability of 68Ga, automation of the radiopharmaceutical production, progress of PET technologies and image analysis methodologies for improved quantitation accuracy, PET radiopharmaceutical regulations as well as radiopharmaceutical chemistry advances. This review presents the prospects of the 68Ga-based radiopharmaceutical development on the basis of the current status of these aspects. 68Ga has demonstrated its applicability for the labelling of small compounds, biological macromolecules as well as nano- and micro-particles promoting the growth of PET field . The major application domain is oncology; however, potential has been demonstrated for imaging of myocardial perfusion, pulmonary perfusion and ventilation as well as inflammation and infection. Imaging of general biologic properties and processes such as proliferation, apoptosis, hypoxia, glycolysis, and angiogenesis have also been investigated. These prerequisites may trigger an explosive progress and introduction of new 68Ga-radiopharmaceuticals into clinics in the nearest future of 5-10 years.
| OAK-B135 A New Strategy for the Synthesis of Gloycoprotein
Dr. Eoin Scanlan completed his degree in Chemistry and Applied Chemistry at the National University of Ireland, Galway, in 2000. He was awarded his Ph.D. degree in 2003 from the University of St. Andrews, U.K., where he worked under the supervision of Professor John Walton. His doctoral thesis focused on the development of oxime oxalate amides as tin-free precursors for radical-mediated synthesis of biologically active lactams. In January 2004 he took a position with Professor Philippe Renaud at the University of Bern, Switzerland, where he investigated the use of organoboranes as free-radical precursors. In July 2005 he moved to the University of Oxford, U.K., where he worked with Professor Ben Davis on the synthesis of complex plant cell wall oligosaccharides and regioselective glycosylation methodology. In March 2008 he was appointed as lecturer in Organic and Medicinal Chemistry at Trinity College Dublin. His group’s research interests include development of novel synthetic methodology for construction of oligosaccharides and glycoconjugates and synthesis of carbohydrate-based therapeutics for treatment of cancer and diabetes.
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