کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
69983 | 48805 | 2013 | 8 صفحه PDF | دانلود رایگان |

A gene coding for a putative thermostable esterase (Tm1160) from the hyperthermophilic bacterium Thermotoga maritima was cloned and expressed in Escherichia coli. The purified enzyme displayed optimal activity at 70 °C and had a half-life of 60 min at 90 °C. It was stable over a range of pHs from 5.0 to 7.5 with an optimum around 5.0–5.5. The enzyme was found to have high acid tolerance and maintained about 50% of its activity even after 60 min of treatment at pH 4.5 and 70 °C. Furthermore, the enzyme exhibited the highest specific activity with p-nitrophenyl butyrate (318 ± 7 s−1 mM−1). Under native conditions, Tm1160 forms a ∼74 kDa dimer in solution. In addition, the esterase Tm1160 could enantioselectively hydrolyze the racemic ketoprofen ethyl ester and with an enantiomeric excess (eep) of 91.4% at a conversion of 41.1%, which makes it as a promising biocatalyst for the chiral resolution of (S)-ketoprofen.
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► The recombinant esterase Tm1160 could form ∼74 kDa dimers in solution.
► Tm1160 have high thermostability and high acid tolerance.
► Tm1160 could enantioselectively hydrolyze the racemic ketoprofen ethyl eater.
Journal: Journal of Molecular Catalysis B: Enzymatic - Volumes 85–86, January 2013, Pages 23–30