Title of article :
Enhancement of pH-stability of a low molecular mass endoglucanase from Fusarium oxysporum by protein pegylation
Author/Authors :
Paul Christakopoulos، نويسنده , , Ekaterini Kourentzi، نويسنده , , Dimitris G. Hatzinikolaou، نويسنده , , Mark Claeyssens، نويسنده , , Dimitris Kekos، نويسنده , , Basil J. Macris، نويسنده ,
Issue Information :
هفته نامه با شماره پیاپی سال 1998
Abstract :
The stability of the low molecular mass endoglucanase (23.2 kDa) from Fusarium oxysporum at alkaline pH was enhanced by chemical modification. Two distinct types of amino acid-specific modifiers were used. The first, either cyanuric chloride activated polyethylene glycol (CC–PEG) or polyethylene glycol succinimidyl succinate active ester (SS–PEG), react (more or less specifically) with protein amino groups. The second type, maleimide polyethylene glycol (Mal–PEG), is specific for cysteinyl residues. The enzyme lost almost all of its activity when modified with CC–PEG, whereas no inactivation was observed with SS–PEG and Mal–PEG. The modified endoglucanase showed remarkably enhanced alkaline pH stability. When acting upon cello-oligosaccharides and 4-methylumbelliferyl cello-oligosaccharides, the enzyme preferentially cleaved the internal glycosidic bonds. The modified enzymes mediated a decrease in the viscosity of carboxymethyl cellulose (CMC) associated with the release of only small amounts of reducing sugar. Thus, the modified enzyme retains the endo character of the native enzyme.
Keywords :
pH-Stability , Polyethylene glycol , Chemical modification , Endoglucanase
Journal title :
Carbohydrate Research
Journal title :
Carbohydrate Research