7u22
From Proteopedia
Mycobacterium tuberculosis RNA polymerase sigma A holoenzyme open promoter complex containing UMN-7
Structural highlights
FunctionRPOA_MYCTA DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Publication Abstract from PubMedRifamycin antibiotics are a valuable class of antimicrobials for treating infections by mycobacteria and other persistent bacteria owing to their potent bactericidal activity against replicating and non-replicating pathogens. However, the clinical utility of rifamycins against Mycobacterium abscessus is seriously compromised by a novel resistance mechanism, namely, rifamycin inactivation by ADP-ribosylation. Using a structure-based approach, we rationally redesign rifamycins through strategic modification of the ansa-chain to block ADP-ribosylation while preserving on-target activity. Validated by a combination of biochemical, structural, and microbiological studies, the most potent analogs overcome ADP-ribosylation, restored their intrinsic low nanomolar activity and demonstrated significant in vivo antibacterial efficacy. Further optimization by tuning drug disposition properties afforded a preclinical candidate with remarkable potency and an outstanding pharmacokinetic profile. Redesign of Rifamycin Antibiotics to Overcome ADP-Ribosylation-Mediated Resistance.,Lan T, Ganapathy US, Sharma S, Ahn YM, Zimmerman M, Molodtsov V, Hegde P, Gengenbacher M, Ebright RH, Dartois V, Freundlich JS, Dick T, Aldrich CC Angew Chem Int Ed Engl. 2022 Oct 12:e202211498. doi: 10.1002/anie.202211498. PMID:36222275[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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