RESUMO
The prevalence of multidrug-resistant (MDR) pathogens combined with a decline in antibiotic discovery presents a major challenge for health care. To refill the discovery pipeline, we need to find new ways to uncover new chemical entities. Here, we report the global genome mining-guided discovery of new lipopeptide antibiotics tridecaptin A5 and tridecaptin D, which exhibit unusual bioactivities within their class. The change in the antibacterial spectrum of Oct-TriA5 was explained solely by a Phe to Trp substitution as compared to Oct-TriA1, while Oct-TriD contained 6 substitutions. Metabolomic analysis of producer Paenibacillus sp. JJ-21 validated the predicted amino acid sequence of tridecaptin A5. Screening of tridecaptin analogues substituted at position 9 identified Oct-His9 as a potent congener with exceptional efficacy against Pseudomonas aeruginosa and reduced hemolytic and cytotoxic properties. Our work highlights the promise of tridecaptin analogues to combat MDR pathogens.
Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Antibacterianos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Humanos , Especificidade de Hospedeiro , Descoberta de Drogas , Lipopeptídeos/farmacologia , Lipopeptídeos/química , PeptídeosRESUMO
The phospholipase A and acyltransferase (PLAAT) family of cysteine hydrolases consists of five members, which are involved in the Ca2+-independent production of N-acylphosphatidylethanolamines (NAPEs). NAPEs are lipid precursors for bioactive N-acylethanolamines (NAEs) that are involved in various physiological processes such as food intake, pain, inflammation, stress, and anxiety. Recently, we identified α-ketoamides as the first pan-active PLAAT inhibitor scaffold that reduced arachidonic acid levels in PLAAT3-overexpressing U2OS cells and in HepG2 cells. Here, we report the structure-activity relationships of the α-ketoamide series using activity-based protein profiling. This led to the identification of LEI-301, a nanomolar potent inhibitor for the PLAAT family members. LEI-301 reduced the NAE levels, including anandamide, in cells overexpressing PLAAT2 or PLAAT5. Collectively, LEI-301 may help to dissect the physiological role of the PLAATs.
Assuntos
Aciltransferases/antagonistas & inibidores , Amidas/química , Amidas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fosfolipases/antagonistas & inibidores , Aciltransferases/química , Células Hep G2 , Humanos , Modelos Moleculares , Fosfolipases/química , Conformação Proteica , Relação Estrutura-AtividadeRESUMO
Mammalian genomes encode seven catalytic proteasome subunits, namely, ß1c, ß2c, ß5c (assembled into constitutive 20S proteasome core particles), ß1i, ß2i, ß5i (incorporated into immunoproteasomes), and the thymoproteasome-specific subunit ß5t. Extensive research in the past decades has yielded numerous potent proteasome inhibitors including compounds currently used in the clinic to treat multiple myeloma and mantle cell lymphoma. Proteasome inhibitors that selectively target combinations of ß1c/ß1i, ß2c/ß2i, or ß5c/ß5i are available, yet ligands truly selective for a single proteasome activity are scarce. In this work we report the development of cell-permeable ß1i and ß5i selective inhibitors that outperform existing leads in terms of selectivity and/or potency. These compounds are the result of a rational design strategy using known inhibitors as starting points and introducing structural features according to the X-ray structures of the murine constitutive and immunoproteasome 20S core particles.