title: LL-A491, a monazomycin-like antibiotic.
abstract: A new antibiotic, designated LL-A491, was isolated by butanol extraction and crystallization from beers of an unidentified streptomycete, Lederle culture A491. LL-A491 was primarily active against gram-positive bacteria and was related to monazomycin. A tentative molecular formula of C(72+/-2) H(144+/-8) O(25+/-1) N for the antibiotic, based on analyses of the crystalline hydrochloride, picrate, and picrolonate salts, is considerably larger than that proposed for monazomycin, from which LL-A491 was not differentiated by paper chromatography. Analysis of the amorphous polyacetate ester suggested 15 to 16 acetylable groups. Upon hydrolysis, LL-A491 liberated ammonia and a reducing sugar which appeared to be mannose. LL-A491 was dextrorotatory, [alpha](D) (25) + 14 degrees , and exhibited only end absorption in the ultraviolet region.
mesh_terms: D000641:Ammonia / Q000032:analysis; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000096:biosynthesis / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D055598:Chemical Phenomena; D002621:Chemistry; D002854:Chromatography, Paper; D005285:Fermentation; D008358:Mannose / Q000032:analysis; D012988:Soil Microbiology; D013057:Spectrum Analysis; D013302:Streptomyces / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D000641:Ammonia; D008358:Mannose