Trimethyllysine hydroxylase (TMLH) is a non-haem Fe(ii) and 2-oxoglutarate dependent oxygenase that catalyses the C-3 hydroxylation of an unactivated C-H bond in l-trimethyllysine in the first step of carnitine biosynthesis. The examination of trimethyllysine analogues as substrates for human TMLH reveals that the enzyme does hydroxylate substrates other than natural l-trimethyllysine.

The pentahaem enzyme cytochrome c nitrite reductase catalyses the reduction of nitrite to ammonia, a key reaction in the biological nitrogen cycle. The enzyme can also transform nitrogen monoxide and hydroxylamine, two potential bound reaction intermediates, into ammonia. Structural and mechanistic aspects of the multihaem enzyme are discussed in comparison with hydroxylamine oxidoreductase, a ...

Unique three-component self-assembly of a cis-blocked 90° Pd(II) acceptor with a mixture of tri- and tetra-imidazole donors led to the self-sorting of a Pd7 molecular boat with an internal nanocavity, which catalyses the Knoevenagel condensation of a series of aromatic aldehydes with 1,3-dimethylbarbituric acid and Meldrum's acid in aqueous media.

Cyclooxygenase catalyses a key step in prostaglandin biosynthesis, and recent work suggests that one isoenzyme, COX-2, has important roles in early stages of pregnancy; it also appears to be involved in the somewhat analogous process of colon tumor formation and spread.

The catalyst system prepared in situ from iron(III) salts, tris(2-pyridylmethyl)amine and a base readily catalyses the intradiol dioxygenation of pyrocatechol in methanol, to primarily afford the half-methyl ester of muconic acid. Dimethyl adipate is obtained by the subsequent, one-step catalytic hydrogenation/esterification, thus providing a green route to this important nylon precursor.

A non-heme iron complex catalyses the oxidation of allylic, benzylic, and aliphatic C-H bonds by O(2). During this reactivity, a ferric hydroperoxide species is observed. The kinetic analysis of this complex's formation may suggest a ferric superoxo species as the initial metal-based oxidant.

beta-Lactamase I catalyses the hydrolysis of penicillins by an acyl-enzyme mechanism. A procedure was developed for determining the rate constants for the acylation and deacylation steps for the good substrates benzylpenicillin and phenoxymethylpenicillin; this depends on determining the fraction of enzyme that is present as acyl-enzyme in the steady state.

A pyrazine bridged ruthenium/palladium bimetallic photocatalyst with peripheral 4,4'-dicarboxyethyl-2,2'-bipyridine ligands, EtOOC-RuPd, is reported, together with its 2,2'-bipyridine analogue. Upon irradiation with visible light, EtOOC-RuPd catalyses the production of hydrogen gas whereas the complex RuPd does not.

Trimethyllysine hydroxylase (TMLH) catalyses C-3 hydroxylation of Nε-trimethyllysine in the first step of carnitine biosynthesis in humans. Studies on TMLH have been hampered by the lack of established chemical methods. We report that an Nε-trimethyllysine analogue that contains the fluoromethyl group can be used as a 1H and 19F NMR probe for studies on TMLH catalysis.

The function of RedH from Streptomyces coelicolor as an enzyme that catalyses the condensation of 4-methoxy-2,2'-bipyrrole-5-carboxaldehyde (MBC) and 2-undecylpyrrole to form the natural product undecylprodiginine has been experimentally proven, and the substrate specificity of RedH has been probed in vivo by examining its ability to condense chemically-synthesised MBC analogues with 2-undecylp...