Staphyloferrin A: a structurally new siderophore from staphylococci.
Two ferric ion-binding compounds, designated staphyloferrin A and B, were detected in the culture filtrates of staphylococci grown under iron-deficient conditions. Staphyloferrin A was isolated from cultures of Staphylococcus hyicus DSM 20459. The structural elucidation of this highly hydrophilic, acid-labile compound revealed a novel siderophore, N2,N5-di-(1-oxo-3-hydroxy-3,4-dicarboxybutyl)-D-ornithine, which consists of one ornithine and two citric acid residues linked by two amide bonds. The two citric acid components of staphyloferrin A provide two tridentate pendant ligands, comprising of a beta-hydroxy, beta-carboxy-substituted carboxylic acid derivative, for octahedral metal chelation. The CD spectrum of the staphyloferrin A ferric complex indicates a predominant A configuration about the ferric ion center. The uptake of ferric staphyloferrin A by S. hyicus obeys Michaelis-Menten kinetics (Km = 0.246 microM; vmax = 82 pmol.mg-1.min-1), indicating active transport of this siderophore. The staphyloferrin A transport system is different from that of the ferrioxamines as shown by an antagonism test. Production of staphyloferrin A is strongly iron-dependent and is stimulated by supplementation of the medium with either D- or L-ornithine. DL-[5-14C]ornithine was incorporated into staphyloferrin A, demonstrating that ornithine is an intermediate in staphyloferrin A biosynthesis.
Konetschny-Rapp
S
S
Institut für Organische Chemie, Universität Tübingen, Federal Republic of Germany.
Jung
G
G
Meiwes
J
J
Zähner
H
H
D000596:Amino Acids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D002942:Circular Dichroism; D002951:Citrates / Q000302:isolation & purification*; D003470:Culture Media / Q000032:analysis; D005290:Ferric Compounds / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009952:Ornithine / Q000031:analogs & derivatives* / Q000302:isolation & purification; D013210:Staphylococcus / Q000032:analysis*; D013237:Stereoisomerism
D000596:Amino Acids; D002951:Citrates; D003470:Culture Media; D005290:Ferric Compounds; C063851:staphyloferrin A; D009952:Ornithine