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Mono-, difluorinated, and thioanalogues of Bombyx mori female sex pheromones (bombykol, 1 ) were designed according to the ab initio calculations. These rationally designated analogues were synthesized using hydroboration and Sonogashira coupling strategy via (5 E ,7 Z )-undecadien-1-ol ( 10 ) as a common intermediate. A new simplified binding assay based on nanoLC-linear ion trap ESI-MS for quantifying complexation of the B. mori pheromone-binding protein (BmPBP) with native ( 1 ) and prepared analogues was developed. The binding properties of native 1 and thioanalogue 4 with PBP were studied in detail. The dissociation constant ( K D ) of 1 and 4 was determined to be 2.1×10 −6 M and 2.4×10 −6 M, respectively. The similar values for both ligands correlated with ab initio calculations. The new binding assay could be used to determine the K D of other PBPs.

An atmospheric molding protocol has been used to prepare an ionic methacrylate-based copolymer sample support chips for MALDI (pMALDI)-MS by targeting selected groups of various monomers copolymerized during molding, namely, carboxy, sulfo, dimethylalkyamino, and trimethylalkylammonium groups. The new disposable array chips provide analyte-oriented enhancement of protein adsorption to the modified substrates without requiring complicated surface coating or derivatization. The MALDI-MS performance of the new ionic copolymer chips was evaluated for lysozyme, beta-lactoglobulin A, trypsinogen and carbonic anhydrase I using washing with solutions prepared in pH or ionic strength steps. On cationic chips, the proteins are washed out at pH lower than their p/ values, and on anionic chips at pH higher than their p/ values. The ability of the microfabricated pMALDI chip set to selectively adsorb different proteins from real samples and to significantly increase their MS-signal was documented for the transmembrane photosystem I protein complex from the green alga Chlamydomonas reinhardtii. The proteins were almost exclusively adsorbed according to calculated pI values and grand average of hydropathy (GRAVY) indexes. The new disposable chips reduce manipulation times and increase measurement sensitivity for real-world proteomic samples. The simple atmospheric molding procedure enables additional proteomic operations to be incorporated on disposable MALDI-MS integrated platforms.

Conditions allowing optically active methyl glycerate to be converted, without racemization, into the 2-O-propargyl derivative, via the 2-O-allyl derivative, are reported. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Conditions are reported which allow to convert optically active methyl glycerate to the 2- O -allyl derivative without racemization. Cross metathesis reactions then lead to analogues of the 2- O -alkyl glycerate part of the moenomycin antibiotics.

Camalexin represents the main phytoalexin in Arabidopsis (Arabidopsis thaliana). The camalexin-deficient phytoalexin deficient 3 (pad3) mutant has been widely used to assess the biological role of camalexin, although the exact substrate of the cytochrome P450 enzyme 71B15 encoded by PAD3 remained elusive. 2-(Indol-3-yl)-4,5-dihydro-1,3-thiazole-4-carboxylic acid (dihydrocamalexic acid) was identified as likely intermediate in camalexin biosynthesis downstream of indole-3-acetaldoxime, as it accumulated in leaves of silver nitrate-induced pad3 mutant plants and it complemented the camalexin-deficient phenotype of a cyp79b2/cyp79b3 double-knockout mutant. Recombinant CYP71B15 heterologously expressed in yeast catalyzed the conversion of dihydrocamalexic acid to camalexin with preference of the (S)-enantiomer. Arabidopsis microsomes isolated from leaves of CYP71B15-overexpressing and induced wild-type plants were capable of the same reaction but not microsomes from induced leaves of pad3 mutants. In conclusion, CYP71B15 catalyzes the final step in camalexin biosynthesis.