Publications by authors named "J Ondeyka"

Boxazomycins A-C are potent broad-spectrum antibiotics isolated from Actinomycetes strain G495-1 in 1987. We now report that boxazomycin A inhibits bacterial growth by selectively inhibiting protein synthesis, its effect is bacteriostatic, and it is equally active against drug resistant bacterial strains. No cross-resistance to protein synthesis inhibitors was observed suggesting that its inhibition is distinct from clinical protein synthesis inhibitors.

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The ever-increasing bacterial resistance to clinical antibiotics is making many drugs ineffective and creating significant treatment gaps. This can be only circumvented by the discovery of antibiotics with new mechanisms of action. We report here the identification of a new tetramic acid, ascosetin, from an Ascomycete using the Staphylococcus aureus fitness test screening method.

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Bacteria continue to evade existing antibiotics by acquiring resistance by various mechanisms, leading to loss of antibiotic effectiveness. To avoid an epidemic from infections of incurable drug-resistant bacteria, new antibiotics with new modes of action are desperately needed. Using a genome-wide mechanism of action-guided whole cell screening approach based on antisense Staphylococcus aureus fitness test technology, we report herein the discovery of altersolanol P (1), a new tetrahydroanthraquinone from an unknown fungus from the Hypocreales isolated from forest litter collected in Puerto Rico.

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Natural products have been major sources of antibacterial agents and remain very promising. Frequent rediscoveries of known compounds hampers progress of new discoveries and demands development and utilization of new methods for rapid biological and chemical dereplication. This paper describes an efficient approach for discovery of new thiazolyl peptides by sensitive-resistant pair screening and dereplication in a time and cost-effective manner at industrial scale.

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Coniothyrione is a xanthone-derived antibiotic reported several years ago by researchers at Merck & Co. Inc. Revision of the position of the chloro substitution was recently proposed on the basis of empirical reinterpretation of the carbon chemical shift data and a hypothetical biosynthetic argument without the acquisition of any new spectral data to support the postulated change in substituent location.

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