Open AccessElemental iron does repress transferrin, haemopexin and haemoglobin receptor expression in Haemophilus influenzae
Author(s) -
Hasan Abdulaziz A,
Holland Julie,
Smith Ann,
Williams Paul
Publication year - 1997
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1997.tb10344.x
Subject(s) - transferrin , transferrin receptor , biochemistry , repressor , chemistry , binding site , protoporphyrin , biology , gene expression , gene , porphyrin
Abstract The iron repressible nature of Haemophilus influenzae transferrin binding proteins suggests a regulatory role for elemental iron in their expression. The existence of a Haemophilus ferric uptake repressor (Fur) binding motif identified in the promoter region of both tbpA and tbpB further supports this hypothesis. However, a recent study using brain heart infusion growth medium suggested that transferrin binding protein synthesis in H. influenzae was haem‐ rather than iron‐regulated. The present study re‐investigates this observation and using a chemically defined medium, we demonstrate that elemental iron haem or protoporphyrin IX can each regulate Haemophilus influenzae transferrin, haemopexin and haemoglobin receptor expression.