A Superoxide Dismutase Maquette That Reproduces the Spectroscopic and Functional Properties of the Metalloenzyme

Journal Article · Sun Jan 01 04:00:00 EST 2006 · Inorg. Chem.

DOI:https://doi.org/10.1021/ic0514344· OSTI ID:914101

Shearer, J; Long, L

Described herein is a nickel superoxide dismutase (NiSOD) maquette ([Ni(SOD{sup M1})]) based on the first 12 residues from the N-terminal sequence of Streptomyces coelicolor NiSOD. The apopeptide (SOD{sup M1}) was prepared by standard solid-phase Fmoc peptide synthesis. SOD{sup M1} will readily coordinate Ni{sup II} in a 1:1 ratio in slightly basic aqueous sodium phosphate buffer (0.1 M; pH = 7.2) forming a lightly colored beige/pink solution. Unlike NiSOD, which is isolated as a 1:1 mixture of oxidized (Ni{sup III}) and reduced (Ni{sup II}) forms, [Ni(SODM1)] can only be isolated in the NiII oxidation state. The UV/vis, X-ray absorption, and CD spectra of [Ni{sup II}(SOD{sup M1})] correspond well with those reported for the reduced form of NiSOD. Despite the fact that [Ni{sup III}(SOD{sup M1})] is not isolable, [Ni(SOD{sup M1})] has an appropriate redox potential to act as an SOD (E{sub 1/2} = 0.70(2) V vs. Ag/AgCl) and in fact will catalytically disproportionate >40 000 equiv of KO{sub 2}.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 914101
• Report Number(s): BNL--78669-2007-JA
• Journal Information: Inorg. Chem., Journal Name: Inorg. Chem. Vol. 45; ISSN 0020-1669; ISSN INOCAJ
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ABSORPTION
BUFFERS
MIXTURES
NICKEL
PEPTIDES
REDOX POTENTIAL
RESIDUES
SODIUM PHOSPHATES
SPECTRA
STREPTOMYCES
SUPEROXIDE DISMUTASE
SYNTHESIS
national synchrotron light source