title: Coordinate regulation of siderophore and exotoxin A production: molecular cloning and sequencing of the Pseudomonas aeruginosa fur gene.
abstract: A 5.9-kb DNA fragment was cloned from Pseudomonas aeruginosa PA103 by its ability to functionally complement a fur mutation in Escherichia coli. A fur null mutant E. coli strain that contains multiple copies of the 5.9-kb DNA fragment produces a 15-kDa protein which cross-reacts with a polyclonal anti-E. coli Fur serum. Sequencing of a subclone of the 5.9-kb DNA fragment identified an open reading frame predicted to encode a protein 53% identical to E. coli Fur and 49% identical to Vibrio cholerae Fur and Yersinia pestis Fur. While there is extensive homology among these Fur proteins, Fur from P. aeruginosa differs markedly at its carboxy terminus from all of the other Fur proteins. It has been proposed that this region is a metal-binding domain in E. coli Fur. A positive selection procedure involving the isolation of manganese-resistant mutants was used to isolate mutants of strain PA103 that produce altered Fur proteins. These manganese-resistant Fur mutants constitutively produce siderophores and exotoxin A when grown in concentrations of iron that normally repress their production. A multicopy plasmid carrying the P. aeruginosa fur gene restores manganese susceptibility and wild-type regulation of exotoxin A and siderophore production in these Fur mutants.
authors: Department of Microbiology/Immunology, University of Colorado Health Sciences Center, Denver 80262.
authors: R W
authors: RW
authors: Prince
authors: C D
authors: CD
authors: Cox
authors: M L
authors: ML
authors: Vasil
mesh_terms: D036002:ADP Ribose Transferases; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000276:immunology; D001427:Bacterial Toxins; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D003429:Cross Reactions; D004352:Drug Resistance, Microbial; D005098:Exotoxins / Q000096:biosynthesis*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics*; D005816:Genetic Complementation Test; D007501:Iron / Q000378:metabolism; D008345:Manganese / Q000494:pharmacology; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D016296:Mutagenesis; D009842:Oligopeptides; D010641:Phenotype; D010860:Pigments, Biological / Q000032:analysis; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics* / Q000276:immunology; D015183:Restriction Mapping; D012641:Selection, Genetic; D017386:Sequence Homology, Amino Acid; D017262:Siderophores / Q000096:biosynthesis*; D037521:Virulence Factors; D001616:beta-Galactosidase / Q000032:analysis; D000097668:Pseudomonas aeruginosa Exotoxin A
chemical_list: D036002:ADP Ribose Transferases; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D005098:Exotoxins; D007501:Iron; D008345:Manganese; D009842:Oligopeptides; D010860:Pigments, Biological; D012097:Repressor Proteins; D017262:Siderophores; D037521:Virulence Factors; D001616:beta-Galactosidase; D000097668:Pseudomonas aeruginosa Exotoxin A; C068477:ferric uptake regulating proteins, bacterial; C042453:pyoverdin