The heme-binding lipoprotein (HbpA) of Haemophilus influenzae: role in heme utilization

Daniel J Morton1, Larissa L Madore, Ann Smith

  • 1Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.

FEMS Microbiology Letters
|November 18, 2005
PubMed

Haemophilus influenzae has an absolute growth requirement for heme and a heme binding lipoprotein (HbpA) has been implicated in the utilization of this essential nutrient. HbpA was identified by examining clones from an H. influenzae genomic library that caused Escherichia coli harboring the clone to bind heme. However, HbpA has not been shown to mediate heme acquisition in H. influenzae. We constructed an insertional mutation of hbpA in a nontypeable H. influenzae strain and demonstrated a role for the gene in utilization of multiple heme sources. This is the first report confirming a role for HbpA in utilization of heme.

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