Duncan J A, Storey K B
Institute of Biochemistry, Carleton University, Ottawa, Ontario, Canada.
Am J Physiol. 1992 Mar;262(3 Pt 2):R517-23. doi: 10.1152/ajpregu.1992.262.3.R517.
The association of glycolytic enzymes with the particulate fraction of the cell was assessed in the brain of the freshwater turtle, Pseudemys scripta elegans, using three different methodologies. Each method showed that a large percentage of each of eight enzymes was bound in brain. The effect of environmental anoxia (5 or 20 h submergence in N2-bubbled water at 7 degrees C) on the distribution of enzymes between free and bound states was analyzed. All three techniques showed a significant increase in the percentages of brain aldolase and glyceraldehyde-3-phosphate dehydrogenase bound during anoxia and no change in lactate dehydrogenase or creatine kinase binding. Two methodologies also showed an increase in the percent bound during anoxia for hexokinase, phosphofructokinase, and phosphoglycerate kinase. An increased association of glycolytic enzymes with structural elements of the cell during anoxia may physically position the glycolytic pathway to facilitate coupling between this ATP-generating pathway and ATP-utilizing processes, such as membrane ion pumps.
采用三种不同方法，评估了淡水龟（滑龟指名亚种）大脑中糖酵解酶与细胞颗粒部分的关联。每种方法均表明，八种酶中的每种酶都有很大比例结合在大脑中。分析了环境缺氧（在7摄氏度的氮气饱和水中浸泡5或20小时）对酶在游离态和结合态之间分布的影响。所有三种技术均显示，缺氧期间大脑醛缩酶和甘油醛-3-磷酸脱氢酶的结合百分比显著增加，而乳酸脱氢酶或肌酸激酶的结合无变化。两种方法还显示，缺氧期间己糖激酶、磷酸果糖激酶和磷酸甘油酸激酶的结合百分比增加。缺氧期间糖酵解酶与细胞结构成分的关联增加，可能会在物理上定位糖酵解途径，以促进这种产生ATP的途径与利用ATP的过程（如膜离子泵）之间的偶联。
