Bacterial heme sources: the role of heme, hemoprotein receptors and hemophores

Curr Opin Microbiol. 2000 Apr;3(2):215-20. doi: 10.1016/s1369-5274(00)00078-3.


The major mechanisms by which Gram-negative bacteria acquire heme from host heme-carrier proteins involve either direct binding to specific outer membrane receptors or release of bacterial hemophores that take up heme from host heme carriers and shuttle it back to specific receptors. The ability to interact with and remove heme from carrier proteins distinguishes heme from conceptually similar siderophore and vitamin B12 receptors. Recent genetic, biochemical and crystallization studies have started to unravel the mechanism and molecular interactions between heme-carrier proteins and components of bacterial heme assimilation systems.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Bacterial Outer Membrane Proteins / chemistry
  • Bacterial Outer Membrane Proteins / metabolism
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism*
  • Biological Transport
  • Carrier Proteins / chemistry
  • Carrier Proteins / metabolism*
  • Gram-Negative Bacteria / chemistry
  • Gram-Negative Bacteria / metabolism*
  • Heme / metabolism*
  • Hemeproteins / chemistry
  • Hemeproteins / metabolism*
  • Iron / metabolism
  • Membrane Proteins / chemistry
  • Membrane Proteins / metabolism


  • Bacterial Outer Membrane Proteins
  • Bacterial Proteins
  • Carrier Proteins
  • Hemeproteins
  • Membrane Proteins
  • tonB protein, Bacteria
  • Heme
  • Iron