title: Iron acquisition mechanisms of Flavobacterium psychrophilum.
abstract: Forty strains of Flavobacterium psychrophilum were tested for the production of siderophores using the universal Chrome Azurol S (CAS) assay. The majority of the strains (85%) were CAS positive (CAS+) and some (15%) were CAS negative (CAS-). The cryptic plasmid pCP1 was carried by all positive strains and was lacking from negative strains. While a weak catechol reaction was detectable in CAS+ culture supernatants, the CAS reaction was, to some extent, heat sensitive, questioning whether the positive reaction was caused only by siderophores. The ability to grow in vitro under iron-restricted conditions did not correlate with the CAS reactivity, as growth of both CAS+ and CAS- strains was similarly impaired under iron restriction induced by 2,2 dipyridyl. Suppressed growth under these conditions was restored by addition of FeCl3, haemoglobin and transferrin for both CAS+ and CAS- strains.
authors.affiliation: Fish Disease Laboratory, Danish Institute for Fisheries Research, Frederiksberg, Denmark. jdm@dfu.min.dk
authors.forename: J D
authors.initials: JD
authors.lastname: Møller
authors.forename: A E
authors.initials: AE
authors.lastname: Ellis
authors.forename: A C
authors.initials: AC
authors.lastname: Barnes
authors.forename: I
authors.initials: I
authors.lastname: Dalsgaard
mesh_terms: D015082:2,2'-Dipyridyl; D005417:Flavobacterium / Q000378:metabolism*; D062385:Hydroxybenzoates / Q000378:metabolism; D007501:Iron / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D017262:Siderophores / Q000096:biosynthesis*; D013045:Species Specificity
chemical_list: D062385:Hydroxybenzoates; D017262:Siderophores; C015076:chrome azurol S; D015082:2,2'-Dipyridyl; D007501:Iron