title: Isolation and characterization of a novel polyether antibiotic of the pyrrolether class, antibiotic X-14885A.
abstract: Antibiotic X-14885A is a polyether antibiotic belonging to the class of these natural acid ionophores known as pyrrolethers. The structure of the antibiotic was elucidated by X-ray crystallographic analysis of the hydrated sodium salt, which crystallized as a tetramer containing four antibiotic and water molecules and four atoms of sodium. Antibiotic X-14885A differs from the most well-known member of the class, A-23187, in two respects: the aromatic N-methylamino group present in the latter is replaced by a phenolic hydroxyl, and one of the four aliphatic methyls is replaced by a proton. Antibiotic X-14885A is active against Gram-positive bacteria and the spirochete, Treponema hyodysenteriae.
mesh_terms: D000900:Anti-Bacterial Agents / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D008968:Molecular Conformation; D011714:Pyrans / Q000302:isolation & purification / Q000633:toxicity; D013045:Species Specificity; D013329:Structure-Activity Relationship; D014208:Treponema / Q000187:drug effects; D014961:X-Ray Diffraction
chemical_list: D000900:Anti-Bacterial Agents; D011714:Pyrans; C039617:antibiotic X 14885A