AN ENZYME-CATALYZED ACYL MIGRATION: A LYSOLECITHIN MIGRATASE

On the Question of an Acyl-enzyme Intermediate in the Chymotrypsin- Catalyzed Hydrolysis of Hydroxamic Acids.

Platinum-catalyzed tandem cycloisomerization reaction of benzoendiynyl esters: regioselective long-range 1,5-acyl migration.

A Pt(II)-catalyzed intramolecular chemo- and regioselective pentannulation/long-range 1,5-acyl migration reaction is described. This cascade cycloisomerization protocol produces a wide variety of benzofulvene diketones in good to excellent yields with exclusively the Z configuration of the exocyclic double bond of the final product. The (18)O isotope experiment together with (13)C NMR, HRMS, an...

Acyl enzyme intermediates in sortase-catalyzed pilus morphogenesis in gram-positive bacteria.

In gram-positive bacteria, covalently linked pilus polymers are assembled by a specific transpeptidase enzyme called pilus-specific sortase. This sortase is postulated to cleave the LPXTG motif of a pilin precursor between threonine and glycine and to form an acyl enzyme intermediate with the substrate. Pilus polymerization is believed to occur through the resolution of this intermediate upon s...

An acyl-covalent enzyme intermediate of lecithin:retinol acyltransferase.

Synthesis of fatty acid retinyl esters determines systemic vitamin A levels and provides substrate for production of visual chromophore (11-cis-retinal) in vertebrates. Lecithin:retinol acyltransferase (LRAT), the main enzyme responsible for retinyl ester formation, catalyzes the transfer of an acyl group from the sn-1 position of phosphatidylcholine to retinol. To delineate the catalytic mecha...

Computational Insights into an Enzyme-Catalyzed [4+2] Cycloaddition

The enzyme SpnF, involved in the biosynthesis of spinosyn A, catalyzes a formal [4+2] cycloaddition of a 22-membered macrolactone, which may proceed as a concerted [4+2] Diels-Alder reaction or a stepwise [6+4] cycloaddition followed by a Cope rearrangement. Quantum mechanics/molecular mechanics (QM/MM) calculations combined with free energy simulations show that the Diels-Alder pathway is favo...