Utilization of transferrin-bound iron by Haemophilus influenzae requires an intact tonB gene.

AUTOR(ES)

Jarosik, G P

RESUMO

Haemophilus influenzae can utilize iron-loaded human transferrin as an iron source for growth in vitro. H. influenzae tonB mutants, containing a chloramphenicol acetyltransferase gene within their tonB genes, could bind iron-charged human transferrin to their cell surfaces, but they were unable to utilize this serum glycoprotein as the sole source of iron for growth in vitro. In contrast, these tonB mutants were able to utilize an iron chelate (ferric ammonium citrate) for growth. Transformation of a tonB mutant with a plasmid encoding a wild-type H. influenzae tonB gene restored the ability of a tonB mutant to utilize iron-charged human transferrin. These results indicate that the uptake of iron from human transferrin by H. influenzae is a TonB-dependent process.

Documentos Relacionados

• Haemophilus somnus Possesses Two Systems for Acquisition of Transferrin-Bound Iron
• Effect of sulphydryl inhibition on the uptake of transferrin-bound iron by reticulocytes
• A functional tonB gene is required for both utilization of heme and virulence expression by Haemophilus influenzae type b.
• Actinobacillus pleuropneumoniae Iron Transport: a Set of exbBD Genes Is Transcriptionally Linked to the tbpB Gene and Required for Utilization of Transferrin-Bound Iron
• Neisseria meningitidis tonB, exbB, and exbD genes: Ton-dependent utilization of protein-bound iron in Neisseriae.