Alkaline treatment has contrasting effects on the structure of deglycosylated and glycosylated forms of glucose oxidase

被引:11
作者
Akhtar, MS [1 ]
Bhakuni, V [1 ]
机构
[1] Cent Drug Res Inst, Div Mol & Struct Biol, Lucknow 226001, Uttar Pradesh, India
关键词
deglycosylation; pH; alkaline treatment; compaction; partial unfolding;
D O I
10.1016/S0003-9861(03)00127-9
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
X-ray crystallographic studies on glucose oxidase showed a strong interaction between carbohydrate and protein moieties of the glycoprotein. However, experimental studies under physiological conditions reported no influence of carbohydrate moiety on the structural and functional properties of glucose oxidase. In order to demonstrate the role of carbohydrate moiety on the structure and stability, we carried out a detailed comparative study on the pH-induced structural changes in the native and deglycosylated forms of glucose oxidase. Our studies demonstrate that at physiological pH both forms of enzyme have very similar structural and stability properties. Acid denaturation also showed similar structural changes in both forms of the enzyme. However, on alkaline treatment contrasting effects on the structure and stability of the two forms of enzyme were observed. The glycosylated enzyme undergoes partial unfolding with decreased stability at alkaline pH; however, a compaction of native conformation and enhanced stability of enzyme was observed for the deglycosylated enzyme under similar conditions. This is the first experimental demonstration of the influence of carbohydrate moiety on structure and stability of glucose oxidase. The studies also indicate the importance of pH studies in evaluating the effect of carbohydrate moiety on the structural and stability properties of glycoprotein. (C) 2003 Elsevier Science (USA). All rights reserved.
引用
收藏
页码:221 / 228
页数:8
相关论文
共 31 条
[1]   Monovalent cation-induced conformational change in glucose oxidase leading to stabilization of the enzyme [J].
Ahmad, A ;
Akhtar, MS ;
Bhakuni, V .
BIOCHEMISTRY, 2001, 40 (07) :1945-1955
[2]   THE DESIGN OF ENZYME SENSORS BASED ON THE ENZYME STRUCTURE [J].
ALVAREZICAZA, M ;
KALISZ, HM ;
HECHT, HJ ;
AUMANN, KD ;
SCHOMBURG, D ;
SCHMID, RD .
BIOSENSORS & BIOELECTRONICS, 1995, 10 (08) :735-742
[3]   REVERSIBLE ACID DISSOCIATION AND HYBRIDIZATION OF LACTIC DEHYDROGENASE [J].
ANDERSON, S ;
WEBER, G .
ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS, 1966, 116 (1-3) :207-&
[4]  
CHU FK, 1978, J BIOL CHEM, V253, P8691
[5]  
DAKHTAR SM, 2002, BIOCHEMISTRY-US, V41, P3819
[6]  
DAKHTAR SM, 2002, BIOCHEMISTRY-US, V41, P7142
[7]  
FISCHER HD, 1980, J BIOL CHEM, V255, P9608
[8]  
GHISLA S, 1974, BIOCHEMISTRY-US, V13, P589, DOI 10.1021/bi00700a029
[9]   Forster energy transfer from tryptophan to flavin in glucose oxidase enzyme [J].
Haouz, A ;
Twist, C ;
Zentz, C ;
de Kersabiec, AM ;
Pin, S ;
Alpert, B .
CHEMICAL PHYSICS LETTERS, 1998, 294 (1-3) :197-203
[10]   MULTIPLE FORMS OF GLUCOSE-OXIDASE WITH DIFFERENT CARBOHYDRATE COMPOSITIONS [J].
HAYASHI, S ;
NAKAMURA, S .
BIOCHIMICA ET BIOPHYSICA ACTA, 1981, 657 (01) :40-51