Authors: Christian Zimmer Tanja Platz Neza Cadez Friedrich Giffhorn GertWieland Kohring
Publish Date: 2006/07/18
Volume: 73, Issue: 1, Pages: 132-140
Abstract
In a screening procedure a pinkcolored yeast was isolated from enrichment cultures with 2R3R−diObenzoyltartrate benzoyltartrate as the sole carbon source The organism saar1 was identified by morphological physiological and 18S ribosomal DNA/internal transcribed spacer analysis as Rhodotorula mucilaginosa a basidiomycetous yeast During growth the yeast hydrolyzed the dibenzoyl ester stoichiometrically to the monoester using the separated benzoate as the growth substrate before the monoester was further cleaved into benzoate and tartrate which were both metabolized The corresponding benzoyl esterase was purified from the culture supernatant and characterized as a monomeric glycosylated 86kDa protein with an optimum pH of 75 and an optimum temperature of 45 °C At 0 °C the esterase still exhibited 20 of the corresponding activity at 30 °C which correlates it to psychrophilic enzymes The esterase could hydrolyze short chain pnitrophenylalkyl esters and several benzoyl esters like benzoylmethyl ester ethyleneglycoldibenzoyl ester phenylbenzoyl ester cocaine and 15anhydrodfructosetribenzoyl ester However feruloylethyl ester was not hydrolyzed The activity characteristics let the enzyme appear as a promising tool for synthesis of benzoylated compounds for pharmaceutical cosmetic or fine chemical applications even at low temperaturesThe provision of 15anhydrodfructosetribenzoyl ester by I Lundt and M Andreassen Organic Chemistry DTU Copenhagen Denmark is gratefully acknowledged We thank F T Peters Toxicology Saarland University Homburg Germany for very helpful assistance in cocaine hydrolyses This study was financially supported by the European Union within the 5th Framework Programme NEPSA under contract no QLK3CT200102400
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