Themed collection Biological oxidation reactions: mechanisms and design of new catalysts

The scope and limitations of oxygenases as catalysts for preparative organic synthesis is discussed.

With computational resources becoming more efficient and more powerful and at the same time cheaper, computational methods have become more and more popular for studies on biochemical and biomimetic systems.

The transformation of non-oxido V^IV to oxido V^IV species under physiological conditions is necessary for a vanadium compound to exhibit pharmacological anti-diabetic activity.

A bio-inspired Mn(II) complex with a linear pentadentate ligand and an alternating NSNSN coordination displays excellent dual SOD/CAT-like antioxidant activity and good stability in aqueous environment.

Agreement between the molecular alignment tensor and the combined effect of four hemes in a cytochrome, revealed by residual dipolar couplings.

An empirical equation, describing the relationship between paramagnetic shifts and axial ligand orientations has been applied to an artificial bis-histidine ferriheme-protein, in order to determine the geometry of the active site.

The structure of the water oxidising complex in the Sr-substituted X-ray crystal structure of photosystem II and its differences relative to the Ca-containing system, have been rationalized by a density functional study.

Two models of tyrosinase containing bidentate ligands with pyrazole moieties are synthesized and characterized with respect to their catalytic activity.

UV-visible absorption spectroelectrochemistry elucidated the different redox behaviours of Fe^III- and Co^III-mimochrome VI artificial enzymes, adsorbed on mesoporous conductive films of ITO.

The steric bulk of tetradentate ligands dictates the relative reactivity patterns of high valent iron oxido/hydroxido tautomers.

Peroxide-bridged binuclear iron(III)-complexes based on bidentate ligands were identified as stable intermediates in the disproportionation of H₂O₂ by tris-homoleptic iron(II)-complexes.

Orbital analysis provides new insight into the Mo/Cu CODH mechanism with a calculated reaction barrier in excellent agreement with experiment.

Factors that lead to coordinative unsaturation in non-heme-Fe(II) enzymes include sterics, facial triad carboxylate H-bonding, and strong cosubstrate donor ligation.

Mechanistic studies revealed a new S = 1/2 intermediate (λ_max = 465 nm) in the reaction of electron-rich aminopyridine Fe(II) complexes with H₂O₂/HOAc.

Organic substrates (specifically cis-1,2-dimethylcyclohexane, DMCH) are oxidized by O₂ in the presence of iron(II)–bispidine complexes.

With regard to excitation by visible light, the low-lying triplet state appears to be an alternative for induction of biological hydroxylation activity.

Bromoperoxidase catalytic activity exerted by oxidated amavadin [V(HIDPA)₂]⁻ (HIDPA = 2,2′-(hydroxyimino) dipropionate) in mono- and bis-protonated forms has been investigated by DFT.

We present a structural model of tyrosinase inhibited by kojic acid. The binding mode on the enzyme is refined by QM/MM calculations.

Survival test passed: the Co₄-oxo core of a polyoxometalate facilitates water oxidation in aqueous solution and thus is of high interest in energy science. The molecule is indeed is a real catalyst surviving the reaction cycle without any detectable structural modification.

Asp137 to Ser replacement in Mycobacterium tuberculosis KatG enlarges a substrate access channel greatly enhancing activation of the pro-drug isoniazid.

This work presents the first detailed study on mechanistic aspects of halide oxidation by non-heme iron complexes.

A nonhaem (μ-oxo)diiron(IV) complex was found to oxidize water to a hydroxyl radical via PCET, instead of forming an O–O bond.

Oxidative C–C bond cleavage of 3,5-di-tert-butylcatechol to 4,6-di-tert-butyl-2-pyrone takes place catalytically on biomimetic iron complexes of a urea-derived facial tridentate ligand.

A cobalt(II) salophen complex enables water oxidation in photoactivated sacrificial cycles under visible light.