An interpretation of the effects of salts on the lactic dehydrogenase of Halobacterium salinarium.
An interpretation of the effects of salts on the lactic dehydrogenase of Halobacterium salinarium.
复制标题
盐对盐杆菌乳酸脱氢酶影响的解释。
DOI：
10.1139/m59-006
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发表时间：
1959
影响因子：
2.8
通讯作者：
R. M. Baxter
中科院分区：
文献类型：
--
作者：
R. M. Baxter
盐生盐杆菌的乳酸脱氢酶在低溶质浓度下不稳定且无活性。在低溶质浓度下，活性的不可逆损失是一级反应，其速率随盐浓度的二次或三次幂而减小。该酶在不同程度上受到各种无机盐和甘油或葡萄糖的保护。氯化钾和甘油也能保护酶不被尿素灭活。在氯化钾存在下酶的活性最高，但其他几种盐作为活化剂也有不同程度的效果。相对于氯化钠或氯化钾的浓度，活化是第三或第四阶的。氯化钾降低酶对其底物的亲和力。甘油不激活该酶，但在氯化钾存在下可增加其活性，这表明该酶与非嗜盐生物的酶不同，其在其天然催化剂中的固定性较低。
The lactic dehydrogenase of Halobacterium salinarium is unstable and inactive at low solute concentrations. The irreversible loss of activity at low solute concentrations is a first-order reaction, the rate of which decreases with the second or third power of the salt concentration. The enzyme is protected to varying degrees by a variety of inorganic salts and by glycerol or glucose. Potassium chloride and glycerol also protect the enzyme against inactivation by urea.The enzyme is most active in the presence of potassium chloride, but several other salts are effective to varying degrees as activators. The activation is of the third or fourth order with respect to sodium or potassium chloride concentration. Potassium chloride decreases the affinity of the enzyme for its substrate. Glycerol does not activate the enzyme, but increases its activity in the presence of potassium chloride.It is suggested that this enzyme differs from enzymes of non-halophilic organisms in being less firmly held in its native cat...