Methylation of Daptomycin Leading to the Discovery of Kynomycin, a Cyclic Lipodepsipeptide Active against Resistant Pathogens
摘要:
Increased usage of daptomycin to treat infections caused by Gram-positive bacterial pathogens has resulted in emergence of resistant mutants. In a search for more effective daptomycin analogues through medicinal chemistry studies, we found that methylation at the nonproteinogenic amino acid kynurenine in daptomycin could result in significant enhancement of antibacterial activity. Termed "kynomycin," this new antibiotic exhibits higher antibacterial activity than daptomycin and is able to eradicate methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) strains, including dapto-mycin-resistant strains. The improved antimicrobial activity of kynomycin was demonstrated in in vitro time-killing assay, in vivo wax worm model, and different mouse infection models. The increased antibacterial activity, improved pharmacokinetics, and lower cytotoxicity of kynomycin, compared to daptomycin, showed the promise of the future design and development of next-generation daptomycin-based antibiotics.
Selective Substrates and Activity-Based Probes for Imaging of the Human Constitutive 20S Proteasome in Cells and Blood Samples
作者:Wioletta Rut、Marcin Poręba、Paulina Kasperkiewicz、Scott J. Snipas、Marcin Drąg
DOI:10.1021/acs.jmedchem.8b00026
日期:2018.6.28
the HyCoSuL approach, we designed and synthesized novel and selective fluorogenic substrates for each of these three constitutive 20S proteasome activities and applied them to assess inhibition of proteasome subunits by MG-132 and a clinically used inhibitor bortezomib. Our results confirm the utility of designed substrates in biochemical assays. Furthermore, selective peptide sequences obtained in this
[EN] BICYCLIC PEPTIDE LIGANDS SPECIFIC FOR TSLP<br/>[FR] LIGANDS PEPTIDIQUES BICYCLIQUES SPÉCIFIQUES DE LA TSLP
申请人:BICYCLETX LTD
公开号:WO2021205161A1
公开(公告)日:2021-10-14
The present invention relates to polypeptides which are covalently bound to molecular scaffolds such that two or more peptide loops are subtended between attachment points to the scaffold. In particular, the invention describes peptides which are high affinity binders of thymic stromal lymphopoietin (TSLP). The invention also includes pharmaceutical compositions comprising said peptide ligands and to the use of said peptide ligands in preventing, suppressing or treating a disease or disorder mediated by TSLP.
Synthesis and Activity of Thioether-Containing Analogues of the Complement Inhibitor Compstatin
作者:Patrick J. Knerr、Apostolia Tzekou、Daniel Ricklin、Hongchang Qu、Hui Chen、Wilfred A. van der Donk、John D. Lambris
DOI:10.1021/cb2000378
日期:2011.7.15
essential for the structural stability and biological activity of many bioactive peptides. However, these bonds are labile to reducing agents, which can limit the therapeutic utility of such peptides. Substitution of a disulfide bond with a reduction-resistant cystathionine bridge is an attractive means of improving stability while imposing minimal structural perturbation to the peptide. We have applied
NeuromedinU (NMU) activates two NMU receptors (NMUR1 and NMUR2) and is a useful antiobesity drug lead. We report discovery of a hexapeptide agonist, 2-thienylacetyl-Trp1-Phe(4-F)2-Arg3-Pro4-Arg5-Asn6-NH2 (4). However, the NMUR1 selectivity and serum stability of this agonist were unsatisfactory. Through a structure–activity relationship study focused on residue 2 of agonist 4, serum stability, and
[EN] FLUORESCENTLY LABELED MOLECULES CONTAINING MODIFIED TRYPTOPHAN<br/>[FR] MOLÉCULES MARQUÉES PAR FLUORESCENCE CONTENANT DU TRYPTOPHANE MODIFIÉ
申请人:SEED RES AND DEV LLC
公开号:WO2016133913A1
公开(公告)日:2016-08-25
The present disclosure relates to new fluorescent molecules that contain N-alkylated or N-acylated tryptophan and do not substantially quench fluorescent labels attached to the molecules, and the use of such molecules in preparing and studying various compounds, such as substrates and inhibitors for assays of enzymes (e.g., caspases, such as caspase-1 which is an important enzyme in inflammation). An enzyme substrate or enzyme inhibitor that contains a modified tryptophan and fluorescent label as disclosed herein can be studied without loss of signal by Förster quenching. By reducing or eliminating this quenching, more useful labeled molecules with improved properties for assay development can be prepared.