Heme uptake in bacterial pathogens.
Iron is an essential nutrient for the survival of organisms. Bacterial pathogens possess specialized pathways to acquire heme from their human hosts. In this review, we present recent structural and biochemical data that provide mechanistic insights into several bacterial heme uptake pathways, encompassing the sequestration of heme from human hemoproteins to secreted or membrane-associated bacterial proteins, the transport of heme across bacterial membranes, and the degradation of heme within the bacterial cytosol to liberate iron. The pathways for heme transport into the bacterial cytosol are divergent, harboring non-homologous protein sequences, novel structures, varying numbers of proteins, and different mechanisms. Congruously, the breakdown of heme within the bacterial cytosol by sequence-divergent proteins releases iron and distinct degradation products.
Department of Molecular Biology and Biochemistry, UCI, Irvine, CA 92697, USA.
Heidi
H
Contreras
Department of Molecular Biology and Biochemistry, UCI, Irvine, CA 92697, USA.
Nicholas
N
Chim
Department of Molecular Biology and Biochemistry, UCI, Irvine, CA 92697, USA.
Alfredo
A
Credali
Department of Molecular Biology and Biochemistry, UCI, Irvine, CA 92697, USA; Department of Pharmaceutical Sciences, UCI, Irvine, CA 92697, USA. Electronic address: celia.goulding@uci.edu.
Celia W
CW
Goulding
D001426:Bacterial Proteins / Q000378:metabolism; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000378:metabolism*; D006094:Gram-Positive Bacteria / Q000378:metabolism*; D006418:Heme / Q000378:metabolism*; D006801:Humans
D001426:Bacterial Proteins; D006418:Heme