... catalytic efficiency mechanism product specificity terpene synthase Terpenoids form the largest class of specialized or secondary metabolites and are widely used as drugs, cosmetics, and fuels [ 1 , 2 ]. Strikingly, more than 70 000 structures, accounting for 25% of known natural products...

... mechanism through the binding of transition state mimics both in solution and in the crystal. 31 P-NMR and tryptophan fluorescence quenching in the presence of AlF 3 and MgF 3 − identified which phosphate is subject to nucleophilic attack by a water molecule. The structures in complex with two transition...

... feedback inhibition by its end product isoleucine. To understand the molecular basis of the high selectivity of the inhibitor and the mechanism of feedback inhibition, we determined the crystal structure of Li CMSC (C-terminal regulatory domain of Li CMS) in complex with isoleucine, and performed...

... of the 4-nitrophenylcarbamate substrate. Hammett σ–ρ analysis suggests that both the non-catalysed and antibody-catalysed reactions proceed by mechanisms in which development of the aryloxyanion of the leaving group is well advanced in the transition state of the rate-determining step. This is probably...

...Peter Prehm The mechanism of hyaluronan biosynthesis in vertebrates had been proposed to occur at the reducing end of growing chains. This mechanism was questioned because a recombinant synthase appeared to add new monosaccharides to the non-reducing end. I reinvestigated this problem...

...James A. Huntington As a tool for understanding biological mechanisms, X-ray crystallography possesses unparalleled power to enlighten, resolve controversy and shift a field of study on to a secure new paradigm. Thanks largely to developments in crystallographic methods, the technique has become...

... to E134A) or to steady state product formation (for the wild-type reaction). The lag phase, with a rate constant of the order of 100s −1 , was independent of the substrate concentration; apparently an induced-fit mechanism governs the formation of enzyme–substrate complexes. The concentration dependencies...

... is not part of the phosphotransfer pathway. To elucidate the mechanism involved, we performed site-directed mutagenesis of the canonical His residue likely to be involved in phosphotransfer. When His-121 was mutated to Ala or Gln, Ser-autophosphorylation was decreased by 50% and transphosphorylation of PDC...

...+ transport mechanism rapid kinetics sarcoplasmic reticulum skeletal muscle Biochem. J. (1999) 339, 351 357 (Printed in Great Britain) 351 Luminal dissociation of Ca2+ from the phosphorylated Ca2+-ATPase is sequential and gated by Mg2+ Richard C. DUGGLEBY, J. Malcolm EAST and Anthony G. LEE1 Division...

... Society, London © 1999 1999 family 27 glycohydrolase mechanism substrate inhibition Biochem. J. (1999) 339, 43 53 (Printed in Great Britain) 43 Lignocellulose degradation by Phanerochaete chrysosporium : purification and characterization of the main a-galactosidase Harry BRUMER III*, Paul F. G...