Purification and characterization of a thermostable alkaline protease produced by Yarrowia lipolytica
Purification of the extracellular prote ase produced by Yarrowia lipolytica was realized in fo ur steps: ammonium sulfate precipitation, anionic exchange (2X) and gel filtration. The enzyme showed m olecular weight of 61.5 kDa (SDS-PAGE) and optimum activity at 52.4°C at pH 10-11. The thermal stability was modified in presence of Ca2+ (10 mM) providing an in crease of 73, 6 and 11% at 40, 50 and 60°C respectively. The thermodynamic parameters (enthalpy and entropy) indicate that the stability of the enzyme is not provided by non-covalent linkages. Furthermore the ion Ca2+ is important for thermodynamic stabilization of the enzymatic structure. The proteolytic activity was inhibited by PMSF; suggesting that the enzyme can be classify in the serine protease family. The results of thermodynamic stability allow classifying the protease studied as thermostable. The importance of the Ca2+ on the thermostability was corroborated; this is the first report on thermal stability and thermodynamic properties of proteases produced by Y. lipolytica.
| Main Authors: | , , , , , , |
|---|---|
| Format: | Digital revista |
| Language: | English |
| Published: |
Universidad Autónoma Metropolitana, División de Ciencias Básicas e Ingeniería
2011
|
| Online Access: | http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1665-27382011000200017 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|