Formation of an Fe(III)-tyrosinate complex during biomineralization of H-subunit ferritin.
An iron(III)-tyrosinate complex was identified in ferritin by ultraviolet-visible and resonance Raman spectroscopies. Previously, a specific amino acid side chain coordinated to iron in ferritin was not known. Ferritin protein was overexpressed in Escherichia coli from complementary DNA sequences of bullfrog red cell ferritin. The purple iron(III)-tyrosinate intermediate that formed during the first stages of iron uptake was replaced by the amber multinuclear iron(III)-oxo complexes of fully mineralized ferritin. Only the H subunit formed detectable amounts of the iron(III)-tyrosinate complex, which may explain the faster rates of iron biomineralization in H- compared to L-type ferritin.
Waldo
G S
GS
Department of Biochemistry, North Carolina State University, Raleigh 27695.
Ling
J
J
Sanders-Loehr
J
J
Theil
E C
EC
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D004912:Erythrocytes / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D005293:Ferritins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D009942:Organometallic Compounds / Q000032:analysis*; D011892:Rana catesbeiana; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D017385:Sequence Homology; D013059:Spectrum Analysis, Raman; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000032:analysis
D046911:Macromolecular Substances; D009942:Organometallic Compounds; D011994:Recombinant Proteins; C079518:iron-tyrosinate complex; D014443:Tyrosine; D005293:Ferritins