title: Isolation and structural characterization of siderophores, madurastatins, produced by a pathogenic Actinomadura madurae.
abstract: Madurastatins Al (1), A2 (2) and A3 (3), novel pentapeptides that were acylated with salicylic acid at the N-terminus, were isolated from the culture broth of a pathogenic Actinomadura madurae IFM 0745 strain. These structures were mainly determined by 2D NMR and MS/MS spectral techniques. The strain produced simultaneously madurastatins B1 (4) and B2 (5) consisting of Ser and salicylic acid moieties. Compounds 1 and 4 had an antibacterial activity against Micrococcus luteus, indicating that the presence of the aziridine ring is essential for such activity. Because 1 has a strong affinity with ferric ion due to the presence of two hydroxamic acids and a salicylic acid, it is considered to be a siderophore that is a low molecular weight iron chelater. The production of siderophores may be one of the characteristics of pathogenic microorganisms.
authors.affiliation: Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468-8503, Japan. kiharada@ccmfs.meijo-u.ac.jp
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Harada
authors.forename: Koji
authors.initials: K
authors.lastname: Tomita
authors.forename: Kiyonaga
authors.initials: K
authors.lastname: Fujii
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Masuda
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Mikami
authors.forename: Katsukiyo
authors.initials: K
authors.lastname: Yazawa
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Komaki
mesh_terms: D039903:Actinobacteria / Q000145:classification / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002851:Chromatography, High Pressure Liquid; D005285:Fermentation; D005290:Ferric Compounds / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D008968:Molecular Conformation; D008970:Molecular Weight; D009842:Oligopeptides / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification*; D012459:Salicylates / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000900:Anti-Bacterial Agents; D005290:Ferric Compounds; D009842:Oligopeptides; D012459:Salicylates