Abstract:
:Mammalian ferritin from horse spleen undergoes an electrochemical or chemical reduction reaction in which each iron atom present is reduced by one electron (2300 electrons per ferritin molecule containing 2300 Fe3+ ions). Midpoint potentials of -190 mV, -310 mV, and -416 mV were determined at pH 7.0, 8.0, and 9.0. This variation of potential with pH indicates that approximately 2 H+ are transferred to the core for each Fe3+ reduced to Fe2+. Mössbauer measurements of partially reduced ferritin give spectra that consist of a ferric quadrupole doublet with a superposed ferrous quadrupole doublet. The relative intensities of these doublets are consistent with the electrochemically determined degree of reduction.
journal_name
Proc Natl Acad Sci U S Aauthors
Watt GD,Frankel RB,Papaefthymiou GCdoi
10.1073/pnas.82.11.3640subject
Has Abstractpub_date
1985-06-01 00:00:00pages
3640-3issue
11eissn
0027-8424issn
1091-6490journal_volume
82pub_type
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