脑半胱氨酸亚磺酸脱羧酶的表征。分子参数及抑制研究。

Characterization of cerebral cysteine sulfinic acid decarboxylase. Molecular parameters and inhibition studies.

作者信息

Heinämäki A A, Perämaa A K, Piha R S

出版信息

Acta Chem Scand B. 1982;36(5):287-90. doi: 10.3891/acta.chem.scand.36b-0287.

DOI:10.3891/acta.chem.scand.36b-0287

Abstract

The molecular properties of cysteine sulfinic acid decarboxylase (EC 4.1.1.29) from calf brain were examined in a crude enzyme preparation. The Stokes radius (42 A) was determined by gel filtration and the sedimentation coefficient, s20,w (6.1 x 10(-13 s) by density gradient centrifugation. Calculation of the molecular weight and frictional ratio gave values of 73,000 and 1.52, respectively. beta-Mercaptopropionic acid and an arginine reagent, phenylglyoxal, were observed to be potent inhibitors of the enzyme. Pyridoxal phosphate, a cofactor of the decarboxylase, was observed to protect the enzyme against phenylglyoxal inhibition. This result indicates that an arginine residue may be located at the active site of cysteine sulfinic acid decarboxylase. The components of taurine metabolism gave little or no inhibition of the decarboxylase. Glutaric acid, malic acid and C-allylglycine, all widely known as potent inhibitors of glutamic acid decarboxylase, only slightly inhibited cysteine sulfinic acid decarboxylase.

摘要

在粗酶制剂中研究了来自小牛脑的半胱氨酸亚磺酸脱羧酶（EC 4.1.1.29）的分子特性。通过凝胶过滤测定斯托克斯半径（42 Å），通过密度梯度离心测定沉降系数s20,w（6.1×10⁻¹³ s）。分子量和摩擦比的计算结果分别为73,000和1.52。观察到β-巯基丙酸和精氨酸试剂苯乙二醛是该酶的有效抑制剂。脱羧酶的辅因子磷酸吡哆醛被观察到可保护该酶免受苯乙二醛的抑制。该结果表明精氨酸残基可能位于半胱氨酸亚磺酸脱羧酶的活性位点。牛磺酸代谢的成分对脱羧酶几乎没有抑制作用。谷氨酸、苹果酸和C-烯丙基甘氨酸，这些都是众所周知的谷氨酸脱羧酶的有效抑制剂，仅轻微抑制半胱氨酸亚磺酸脱羧酶。