English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

The mode of action of DuP 721 was investigated. This compound was active primarily against gram-positive bacteria, including multiply resistant strains of staphylococci. Although inactive against wild-type Escherichia coli, DuP 721 did inhibit E. coli when the outer membrane was perturbed by genetic or chemical means. Pulse-labeling studies with E. coli PLB-3252, a membrane-defective strain, showed that DuP 721 inhibited amino acid incorporation into proteins. The 50% inhibitory concentration of DuP 721 for protein synthesis was 3.8 micrograms/ml, but it was greater than 64 micrograms/ml for RNA and DNA syntheses. The direct addition of DuP 721 to cell-free systems did not inhibit any of the reactions of protein synthesis from chain initiation through chain elongation with either synthetic or natural mRNA as template. However, cell extracts prepared from DuP 721 growth-arrested cells were defective in initiation-dependent polypeptide synthesis directed by MS2 bacteriophage RNA. These cell-free extracts were not defective in polypeptide elongation or in fMet-tRNA(fMet)-dependent polypeptide synthesis stimulated by poly(G.U). We conclude, therefore, that DuP 721 exerts its primary action at a step preceding the interaction of fMet-tRNA(fMet) and 30S ribosomal subunits with the initiator codon.

Mechanism of action of DuP 721: inhibition of an early event during initiation of protein synthesis