Dataset Information

The Role of Coordination Environment and pH in Tuning the Oxidation Rate of Europium(II).

ABSTRACT: The EuII/III redox couple offers metal-based oxidation-sensing with magnetic resonance imaging making the study of EuII oxidation chemistry important in the design of new probes. Accordingly, we explored oxidation reactions with a set of EuII -containing complexes. Superoxide formation from the reaction between EuII and dioxygen was observed using electron paramagnetic resonance spectroscopy. Additionally, oxidation kinetics of three EuII -containing complexes with bromate and glutathione disulfide at pH values, including 5 and 7, is reported. In the reaction with bromate, the oxidation rate of two of the complexes increased by 7.3 and 6.7 times upon decreasing pH from 7 to 5, but the rate increased by 17 times for a complex containing amide functional groups over the same pH range. The oxidation rate of a fluorobenzo-functionalized cryptate was relatively slow, indicating that the ligand used to impart thermodynamic oxidative stability might also be useful for controlling oxidation kinetics.

SUBMITTER: Ekanger LA

PROVIDER: S-EPMC5266649 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The Role of Coordination Environment and pH in Tuning the Oxidation Rate of Europium(II).

Ekanger Levi A LA Basal Lina A LA Allen Matthew J MJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20161219 5

The EuII/III redox couple offers metal-based oxidation-sensing with magnetic resonance imaging making the study of EuII oxidation chemistry important in the design of new probes. Accordingly, we explored oxidation reactions with a set of EuII -containing complexes. Superoxide formation from the reaction between EuII and dioxygen was observed using electron paramagnetic resonance spectroscopy. Additionally, oxidation kinetics of three EuII -c ...[more]

PMID: 27897355

Similar Datasets

Project description:Metalloenzymes catalyze a variety of reactions using a limited number of natural amino acids and metallocofactors. Therefore, the environment beyond the primary coordination sphere must play an important role in both conferring and tuning their phenomenal catalytic properties, enabling active sites with otherwise similar primary coordination environments to perform a diverse array of biological functions. However, since the interactions beyond the primary coordination sphere are numerous and weak, it has been difficult to pinpoint structural features responsible for the tuning of activities of native enzymes. Designing artificial metalloenzymes (ArMs) offers an excellent basis to elucidate the roles of these interactions and to further develop practical biological catalysts. In this review, we highlight how the secondary coordination spheres of ArMs influence metal binding and catalysis, with particular focus on the use of native protein scaffolds as templates for the design of ArMs by either rational design aided by computational modeling, directed evolution, or a combination of both approaches. In describing successes in designing heme, nonheme Fe, and Cu metalloenzymes, heteronuclear metalloenzymes containing heme, and those ArMs containing other metal centers (including those with non-native metal ions and metallocofactors), we have summarized insights gained on how careful controls of the interactions in the secondary coordination sphere, including hydrophobic and hydrogen bonding interactions, allow the generation and tuning of these respective systems to approach, rival, and, in a few cases, exceed those of native enzymes. We have also provided an outlook on the remaining challenges in the field and future directions that will allow for a deeper understanding of the secondary coordination sphere a deeper understanding of the secondary coordintion sphere to be gained, and in turn to guide the design of a broader and more efficient variety of ArMs.

Dataset Information

The Role of Coordination Environment and pH in Tuning the Oxidation Rate of Europium(II).

Publications

The Role of Coordination Environment and pH in Tuning the Oxidation Rate of Europium(II).

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets