The hormone-sensitive lipase from Psychrobacter sp. TA144: New insight in the structural/functional characterization |
| |
Authors: | Concetta De Santi Maria Luisa Tutino Luigi Mandrich Maria Giuliani Ermenegilda Parrilli Pompea Del Vecchio Donatella de Pascale |
| |
Affiliation: | 1. Institute of Protein Biochemistry, CNR, Via Pietro Castellino 111, I-80131 Naples, Italy;2. Department of Organic Chemistry and Biochemistry, University of Naples Federico II, Complesso Universitario Monte Sant’Angelo, Via Cinthia 4, I-80126 Naples, Italy;3. School of Biotechnological Sciences, University of Naples Federico II, Complesso Universitario Monte Sant’Angelo, Via Cinthia 4, I-80126, Naples, Italy;4. Department of Chemistry “Paolo Corradini”, University of Naples Federico II, Complesso Universitario Monte Sant’Angelo, Via Cinthia 4, I-80126 Naples, Italy |
| |
Abstract: | Cold-adapted esterases and lipases have been found to be dominant activities throughout the cold marine environment, indicating their importance in bacterial degradation of the organic matter. lip2 Gene from Psychrobacter sp. TA144, a micro-organism isolated from the Antarctic sea water, was cloned and over-expressed in Escherichia coli. The recombinant protein (PsyHSL) accumulated in the insoluble fraction from which it was recovered in active form, purified to homogeneity and deeply characterised. Temperature dependence of PsyHSL activity was typical of psychrophilic enzymes, with an optimal temperature of 35 °C at pH 8.0. The enzyme resulted to be active on pNP-esters of fatty acids with acyl chain length from C2 to C12 and the preferred substrate was pNP-pentanoate showing a kcat = 26.2 ± 0.1 s−1, KM = 0.122 ± 0.006 mM and a kcat/KM = 215 ± 11 mM−1 s−1. The enzyme was strongly inhibited by Hg2+, Zn2+, Cu2+, Fe3+, Mn2+ ions and it resulted to be activated in presence of methanol and acetonitrile, with calculated C50 values of 1.98 M and 0.92 M, respectively. |
| |
Keywords: | Psychrophilic micro-organisms Cold-active enzymes α/β hydrolase fold Ester synthesis Esterases Lipases |
本文献已被 ScienceDirect 等数据库收录! |
|