The gram-positive bacterium Streptomyces noursei ATCC 11455 produces a complex mixture of polyene macrolides generally termed nystatins. Although the structures for nystatins A(1) and A(3) have been reported, the identities of other components of the nystatin complex remain obscure. Analyses of the culture extract from the S. noursei wild type revealed the presence of several nystatin-related c...

Previous studies have shown that polyene antibiotics alter permeability in sensitive fungi and thus lead to the loss of essential cytoplasmic constituents, which ultimately culminates in cell death (l-3). Subsequent investigations have led to the contention that the selective toxicity of the polyene antibiotics is due to interaction with a component present only in the membrane of sensitive org...

The potentiation of the antiviral activity of acyclovir [9-[(2-hydroxyethoxy)methyl]guanine] by polyene macrolide antibiotics has been studied as a function of the macrolide structure. The 12 polyenes chosen for this study represented the major structural groups of these antibiotics and induced in mammalian cells repairable membrane alterations or irreversible cell damage. The potentiating acti...

The susceptibility of promastigote of Leishmania major to Nystatin in vitro was examined. L. major (MHOM/PK/88/DESTO) promastigote were cultured in medium 199 supplemented with 10% heat inactivated foetal bovine serum and 2% urine. The growth of the promastigote was monitored in the absence and presence of the experimental compound (Nystatin) for upto 5 days post-inoculation. The EC50 value (th...

Carotenoids possessing a carbonyl group along their polyene backbone exhibit unique excited state properties due to the occurrence of intramolecular charge transfer (ICT) in the excited state. In fact, the ICT characteristics of naturally occurring carbonyl carotenoids play an essential role in the highly efficient energy transfer that proceeds in aquatic photosynthetic antenna systems. In the ...

Kinsky, Stephen C. (Washington University, St. Louis, Mo.). Effect of polyene antibiotics on protoplasts of Neurospora crassa. J. Bacteriol. 83:351-358. 1962.-The polyene antibiotics nystatin, amphotericin B, and filipin induced shrinkage of Neurospora crassa protoplasts stabilized in sucrose. At low concentrations of filipin (5 mug per ml), or higher concentrations of nystatin and amphotericin...

Previous studies have shown that polyene antibiotics alter permeability in sensitive fungi and thus lead to the loss of essential cytoplasmic constituents, which ultimately culminates in cell death (l-3). Subsequent investigations have led to the contention that the selective toxicity of the polyene antibiotics is due to interaction with a component present only in the membrane of sensitive org...

A novel xanthomonadin-dialkylresorcinol hybrid named arcuflavin was identified in Azoarcus sp. BH72 by a combination of feeding experiments, HPLC-MS and MALDI-MS and gene clusters encoding the biosynthesis of this non-isoprenoid aryl-polyene containing pigment are reported. A chorismate-utilizing enzyme from the XanB2-type producing 3- and 4-hydroxybenzoic acid and an AMP-ligase encoded by thes...

Viridenomycin is a structurally challenging, potentially biologically valuable molecule which has yet to succumb to total synthesis. Its instability, perhaps particularly associated with the northern polyene may contribute to the difficulties of piecing this molecule together. The synthesis of northern polyene models, including potentially stabilised analogues incorporating benzene rings as Z-a...

The clinically used antifungal polyene amphotericin B was conjugated, via the mycosamine and aglycon moieties, to fluorophores.