Please use this identifier to cite or link to this item:
|Type:||Artigo de periódico|
|Title:||The Thermal Stability Of A Castor Bean Seed Acid Phosphatase.|
|Author:||Granjeiro, Paulo Afonso|
Cavagis, Alexandre Donizeti Martins
de Campos Leite, Luciana
Ferreira, Carmen Veríssima
Granjeiro, José Mauro
|Abstract:||The effect of temperature on the activity and structural stability of an acid phosphatase (EC 220.127.116.11.) purified from castor bean (Ricinus communis L.) seeds have been examined. The enzyme showed high activity at 45 degrees C using p-nitrophenylphosphate (p-NPP) as substrate. The activation energy for the catalyzed reaction was 55.2 kJ mol(-1) and the enzyme maintained 50% of its activity even after 30 min at 55 degrees C. Thermal inactivation studies showed an influence of pH in the loss of enzymatic activity at 60 degrees C. A noticeable protective effect from thermal inactivation was observed when the enzyme was preincubated, at 60 degrees C, with the reaction products inorganic phosphate-P (10 mM) and p-nitrophenol-p-NP(10 mM). Denaturation studies showed a relatively high transition temperature (Tm) value of 75 degrees C and an influence of the combination of Pi (10 mM) and p-NP (10 mM) was observed on the conformational behaviour of the macromolecule.|
|Citation:||Molecular And Cellular Biochemistry. v. 266, n. 1-2, p. 11-5, 2004-Nov.|
|Appears in Collections:||Unicamp - Artigos e Outros Documentos|
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.