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The metalloprotease (Mpl) of Listeria monocytogenes is a thermolysin-like protease that mediates the maturation of a broad-range phospholipase C, whose function contributes to the ability of this food-borne bacterial pathogen to survive intracellularly. Mpl is made as a proprotein that undergoes maturation by proteolytic cleavage of a large N-terminal prodomain. In this study, we identified the N terminus of mature Mpl and generated Mpl catalytic mutants to investigate the mechanism of Mpl maturation. We observed that Mpl activity was a prerequisite for maturation, suggesting a mechanism of autocatalysis. Furthermore, using a strain of L. monocytogenes expressing both the wild-type form and a catalytic mutant form of Mpl simultaneously, we determined that in vivo maturation of Mpl occurs exclusively by an intramolecular autocatalysis mechanism.

Research has been conducted on the organometallic compounds. The organolithium reagent addition to corannulene has been investigated and the route to 1-alkyl-1,2-dihydrocorannulenes has been developed and is described.

Research has been conducted on the bacterial plasmid-encoded organomercury lyase. The protein and solvent components of this lyase-mediated protonolysis of pi-hydroxymercuribenzoate have been investigated via the study of lyase's cysteine residues and the kinetic activity and turnover abilities of the mutant and wild type enzymes and the details are reported.

Research has been conducted on the catalytic asymmetric acyl halide-aldehyde cyclocondensation reaction. The implementation of the reaction design is described and the results indicate that the reaction strategy allows to employ differentially substituted organocuprates in the 4-substituted 2-oxetanone ring opening.

The authors review the publications on biological methylation. The topics of interest include bioalkylation, metalloids' methylation, arsenic methylation, antimony biomethylation and enzymology of biomethylation.

Research has been conducted on the coupling reaction which involves allenic and propargylic palladium species. The regioselectivity controlling factors for this reaction have been verified and the details are presented.

Research has been conducted on the pipecolic acid derivatives. The asymmetric synthesis of these derivatives from the functionalized beta-amino alcohols has been carried out and the reactions between the unsaturated organilithium reagents and oxazolidines have been explored.

Research has been conducted on the anthracene derivatives with the 2,2,6,6-tetramethyl-1-piperidinyloxy radicals. The preparation of these derivatives has been carried out and the results of the photodimerization reaction are reported.

Research has been conducted on the tert-butanesulfinyl aldimines and ketimines which serve as precursors in the 1,2-amino alcohol synthesis. The general protocols for the unbranched alkyl, branched alkyl and aryl organometallic reagent addition to N-sulfinyl aldimines and ketimines are described.

Research has been conducted on the coumarins. The combinatorial synthesis of the coumarin library carried out under mild conditions in utilizing silyl linker based macrobeads as solid supporters has been developed and described.

Research has been conducted on the stannylated oxazolines. The addition of these oxazolines to the bromonaphthoquinones at the carbonyl group vicinal to the bromine atom has been investigated and the results are presented.

Research has been conducted on the alkoxythiophenes which represent subunits for the synthesis of the thermotropic liquid crystals by the palladium-catalyzed cross-coupling reactions and organometallic derivatization. The synthesis of these alkoxythiophenes has been carried out and the results are reported.

Research has been conducted on the imines derived from naphthalene-1-carbaldehyde and acyclic alpha,beta-unsaturated aldehydes. The reaction of these imines with the organolithium reagents has been investigated and the results indicate that it depends on the characteristic nature of the imine nitrogen atom substituent.

Research has been conducted on the arylsulfonylhydrazones. The reaction of the arylsulfonylhydrazones of aldehydes and ketones with alpha-metalated sulfones has been investigated with respect to developing a practical olefination method, and the results are discussed.

Research has been conducted on the open-chain cyclic diketons. The reaction of these diketons with specific omega-alkenyl organometallics has been examined and the results indicate that this reaction leads to 1,2-diols bonded to terminal olefinic chains.

Research has been conducted on the organometallic cyclobutadieno-fused dehydroannulenes. The synthesis, spectroscopic and structural characterization of these dehydroannulenes have been investigated and the use of the strategy developed by Vollhardt and Youngs has been described.

Research has been conducted on the organometallic rhenium species. The use of bis(trimethylsilyl) peroxide as an oxidant in place of aqueous hydrogen peroxide in replacing these compounds by inorganic rhenium oxides is discussed.

Research has been conducted on the sulfonimines. The reaction of these sulfonimines with crotyl bromide and indium in aqueous media that gave alpha-crotylation products has been investigated and the results are presented.

Research has been conducted on the dialkyl-substituted allyl chloride derivatives. The regioselective palladium-catalyzed coupling reactions of these derivatives with allylstannanes and benzylidenemalonitrile that give functionalized 1,7-octadienes have been investigated and discussed.

Analysis of the influence of a selenoorganic compound, ebselen on infarct size in a canine coronary artery occlusion-reperfusion model shows that ebselen causes a decrease in myocardial-reperfusion injury and reduces the infarct size. The infarct size reduction by ebselen correlates to the decrease in myeloperoxidase activity in ischemic myocardium and rise in reduced glutathione levels. Ebselen treatment has no effect on the regional myocardium, reduced glutathione levels, the regional myocardial blood flow and hemodynamic parameters involved in the experimental studies.