Acquisition of iron by the non-siderophore-producing Pseudomonas fragi.
The iron requirement, siderophore production and iron uptake mechanisms of the type strain Pseudomonas fragi ATCC 4973 and five P. fragi isolates from meat were analysed. The strains exhibited a high sensitivity to iron starvation: their growth was strongly inhibited in medium supplemented with the iron chelator ethylenediamine di(hydroxyphenylacetic acid) or in medium treated with 8-hydroxyquinoline to remove contaminating iron. No siderophores were detectable in the growth supernatants of iron-starved cells. Cross-feeding experiments in iron-depleted medium showed, however, that the bacterial growth could be strongly stimulated by siderophores of foreign origin including desferriferrioxamine B, enterobactin and some pyoverdines. Moreover, all the strains were capable of efficiently using the iron sources present in their natural environment, i.e., transferrin, lactoferrin and haemoglobin. Iron starvation led to the specific production of supplementary outer-membrane proteins of apparent molecular mass ranging from 80 to 88 kDa. Furthermore, growth in the presence of exogenous siderophores resulted, in some strains, in the induction of siderophore-mediated iron uptake systems. For one strain the concomitant synthesis of an iron-regulated, siderophore-inducible outer-membrane protein was observed.
Champomier-Vergès
Marie-Christine
MC
Laboratoire de Recherches sur la Viande, Institut National de la Recherche Agronomique, 78352 Jouyen-Josas, France.
Stintzi
Alain
A
Laboratoire de Microbiologie et Génétique, Unité de Recherche Associée au Centre National de la Recherche Scientifique no. D-1481, Université Louis-Pasteur, 28 rue Goethe, 67083 Strasbourg, France.
Meyer
Jean-Marie
JM
Laboratoire de Microbiologie et Génétique, Unité de Recherche Associée au Centre National de la Recherche Scientifique no. D-1481, Université Louis-Pasteur, 28 rue Goethe, 67083 Strasbourg, France.
D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis / Q000235:genetics; D005029:Ethylenediamines / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D007501:Iron / Q000378:metabolism* / Q000494:pharmacology; D007502:Iron Chelating Agents / Q000494:pharmacology; D008460:Meat / Q000382:microbiology; D008667:Metalloproteins / Q000378:metabolism; D015125:Oxyquinoline / Q000494:pharmacology; D011549:Pseudomonas / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000378:metabolism; D016958:Pseudomonas putida / Q000378:metabolism; D017262:Siderophores / Q000494:pharmacology; D013045:Species Specificity
D001425:Bacterial Outer Membrane Proteins; D005029:Ethylenediamines; D007502:Iron Chelating Agents; D008667:Metalloproteins; D017262:Siderophores; C011813:ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid); D015125:Oxyquinoline; D007501:Iron