The
The gene encoding the cyanobacterial ferritin
- NSF-PAR ID:
- 10083591
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 116
- Issue:
- 6
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 2058-2067
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The
syn andanti isomers of [FeIV(O)(TMC)]2+(TMC=tetramethylcyclam) represent the first isolated pair of synthetic non‐heme oxoiron(IV) complexes with identical ligand topology, differing only in the position of the oxo unit bound to the iron center. Both isomers have previously been characterized. Reported here is that thesyn isomer [FeIV(Osyn )(TMC)(NCMe)]2+(2 ) converts into itsanti form [FeIV(Oanti )(TMC)(NCMe)]2+(1 ) in MeCN, an isomerization facilitated by water and monitored most readily by1H NMR and Raman spectroscopy. Indeed, when H218O is introduced to2 , the nascent1 becomes18O‐labeled. These results provide compelling evidence for a mechanism involving direct binding of a water moleculetrans to the oxo atom in2 with subsequent oxo–hydroxo tautomerism for its incorporation as the oxo atom of1 . The nonplanar nature of the TMC supporting ligand makes this isomerization an irreversible transformation, unlike for their planar heme counterparts. -
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