Structural highlights
Function
[HASA_SERMA] Can bind free heme and also acquire it from hemoglobin. Conveys heme from hemoglobin to the HasR receptor which releases it into the bacterium. HasR alone can take up heme but the synergy between HasA and HasR increases heme uptake 100-fold.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Free iron availability is strongly limited in vertebrate hosts, making the iron acquisition by siderophores inappropriate. Pathogenic bacteria have developed various ways to use the host's iron from iron-containing proteins. Serratia marcescens can use the iron from hemoglobin through the secretion of a hemophore called HasA, which takes up the heme from hemoglobin and shuttles it to the receptor HasR, which in turn, releases heme into the bacterium. We report here the first crystal structure of such a hemophore, bound to a heme group at two different pH values and at a resolution of 1.9 A. The structure reveals a new original fold and suggests a hypothetical mechanism for both heme uptake and release.
The crystal structure of HasA, a hemophore secreted by Serratia marcescens.,Arnoux P, Haser R, Izadi N, Lecroisey A, Delepierre M, Wandersman C, Czjzek M Nat Struct Biol. 1999 Jun;6(6):516-20. PMID:10360351[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Letoffe S, Ghigo JM, Wandersman C. Iron acquisition from heme and hemoglobin by a Serratia marcescens extracellular protein. Proc Natl Acad Sci U S A. 1994 Oct 11;91(21):9876-80. PMID:7937909
- ↑ Ghigo JM, Letoffe S, Wandersman C. A new type of hemophore-dependent heme acquisition system of Serratia marcescens reconstituted in Escherichia coli. J Bacteriol. 1997 Jun;179(11):3572-9. PMID:9171402
- ↑ Arnoux P, Haser R, Izadi N, Lecroisey A, Delepierre M, Wandersman C, Czjzek M. The crystal structure of HasA, a hemophore secreted by Serratia marcescens. Nat Struct Biol. 1999 Jun;6(6):516-20. PMID:10360351 doi:10.1038/9281