A general assay for monitoring catalysis by fluorescence in real time has been developed by use of an antibody sensor. The sensor consists of a product-specific antibody tightly bound to a product analogue covalently labeled with the fluorescent tag acridone. Acridone fluorescence is quenched in the bound state. The reaction is monitored by following the fluorescence increase caused by displacement of the acridonelabeled product from the antibody combining site by the released product. Fluorescence detection of enzymatic hydrolysis of a b-galactoside and butyrate by b-galactosidase and esterase, respectively, are demonstrated. The assay operates by modulation of fluorescence intensity at 445 nm, a signal compatible with currently available instruments measuring in 96-well or 384-well plastic microtiter plates. The method is potentially general and only limited by binding selectivities of the product versus the substrate that can be encountered in antibodies.

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ChemInform Abstract Optically active bicyclo(3.2.0)heptenols such as (II) or (IV), which are central building blocks for the synthesis of chiral cyclobutane and -pentane systems, are prepared with up to >99% e.e. by lipase catalyzed resolution of their butyrates (I) or (III).ubstituents at C-7, vicinal to the reaction site, reduce both enantioselectivity and reaction rate, whereas variation of the acid moiety shows smaller influence. Among the lipases tested, those from Pseudomonas sp. (P, AK, SAM II) give the best results. In the case of ±)-(III), both antipodes of the alcohol (IV) can be obtained by variation of the lipase used.