INHIBITION OF GLUTAMIC DEHYDROGENASE BY PYRIDOXAL 5-PHOSPHATE
INHIBITION OF GLUTAMIC DEHYDROGENASE BY PYRIDOXAL 5-PHOSPHATE
复制标题
DOI：
10.1021/bi00873a017
复制
发表时间：
1966-01-01
期刊：
影响因子：
2.9
通讯作者：
CHURCHIC.JE
中科院分区：
文献类型：
--
作者：
ANDERSON, BM;ANDERSON, CD;CHURCHIC.JE
牛肝谷氨酸脱氢酶在 34°C 下与 5[image]-磷酸吡哆醛一起孵育可灭活。该酶的谷氨酸和丙氨酸脱氢酶活性同时丧失。 5[image]-磷酸吡哆醛的存在可防止酶在高蛋白质浓度下聚集。催化活性和聚集能力的恢复可以通过失活酶的透析来完成。光谱证据表明，灭活过程是通过与酶的氨基形成希夫碱进行的。硼氢化钠还原吡哆醛 5[image]-磷酸灭活酶，产生稳定的吡啶酚-酶衍生物，不能通过透析重新激活。通过荧光光谱研究吡啶氧酶。在吡啶酚酶的酸水解产物中鉴定出e-吡啶酚赖氨酸。谷氨酸脱氢酶也被证明可以被取代的苯甲醛灭活。研究了取代基对失活过程的影响。
Bovine liver glutamic dehydrogenase is inactivated by incubation at 34[degree] with pyridoxal 5[image]-phosphate. Both the glutamic and alanine dehydrogenase activities of the enzyme are lost simultaneously. The presence of pyridoxal 5[image]-phosphate prevents aggregation of the enzyme at high protein concentrations. Restoration of catalytic activity and the ability to aggregate can be accomplished by dialysis of the inactivated enzyme. Spectral evidence is presented to indicate that the inactivation proceeds through Schiff base formation with amino groups of the enzyme Sodium borohydride reduction of the pyridoxal 5[image]-phosphate inactivated enzyme produces a stable pyridoxyl-enzyme derivative that cannot be reactivated by dialysis. The pyridoxy-enzyme was studied through fluorescence spectroscopy. e -Pyridaxyllysine was identified in acid hydrolysates of the pyridoxyl-enzyme. Glutamic dehydrogenase was also demonstrated to be inactivated by substituted benzaldehydes. Substituent effects on the inactivation process were investigated.