Utilization of enterobactin and other exogenous iron sources by Haemophilus influenzae, H. parainfluenzae and H. paraphrophilus.

摘要: Summary: The ability of Haemophilus influenzae, H. parainfluenzae and paraphrophilus to utilize iron complexes, iron-proteins exogenous microbial siderophores was evaluated. In a plate bioassay, all three species used not only ferric nitrate but also the chelates citrate, nitrilotriacetate 2,3-dihydroxybenzoate. Each examined haemin, haemoglobin haem-albumin as sources although influenzae could acquire from transferrin or complexed with haptoglobin. None haemophili obtained ferritin lactoferrin aerobactin desferrioxamine B. However, phenolate siderophore enterobactin supplied both paraphrophilus, DNA isolated organisms hybridized probe prepared Escherichia coli receptor gene fepA. addition, monospecific polyclonal antiserum raised against E. 81 kDa (FepA) recognized an iron-repressible outer membrane protein (OMP) in between 80 82 (depending on strain). This anti-FepA serum did cross-react any OMPs influenzae. each were probed antisera 74 Cir IutA (aerobactin receptor) proteins coli. Apart one strain (NCTC 10665), which OMP about cross-reacted anti-IutA sera, no cross-reactivity observed Cir, paraphrophilus. Thus, possess functional iron-uptake system, siderophore-dependent siderophore-independent high-affinity iron-sequestering systems are now known be expressed genus Haemophilus.