Ota A, Nakashima A, Mori K, Nagatsu T
Department of Physiology, Institute for Comprehensive Medical Science, School of Medicine, Fujita Health University, Aichi, Japan.
Neurosci Lett. 1997 Jun 20;229(1):57-60. doi: 10.1016/s0304-3940(97)00418-7.
N-Terminus-deleted mutants and wild-type human tyrosine hydroxylase type 1 were expressed in Escherichia coli (E. coli) and utilized to investigate the dopamine-induced decrease in the enzyme catalytic activity and also to identify the specific portion in the N-terminus that affects the efficiency of the inhibitory action of dopamine. Supernatants of bacterial lysates were used as enzyme samples. The pH profiles of the enzyme catalytic activity were affected according to the degree of the deletion. The deletion up to 39 amino acid residues was enough to abolish the inhibitory effect of dopamine in the basic pH range. These results suggest that the inhibition by dopamine of tyrosine hydroxylase activity is closely related to the amino acid sequence in the N-terminus of the enzyme.
N端缺失突变体和野生型人1型酪氨酸羟化酶在大肠杆菌（E. coli）中表达，并用于研究多巴胺诱导的酶催化活性降低，同时鉴定N端中影响多巴胺抑制作用效率的特定部分。细菌裂解物的上清液用作酶样品。酶催化活性的pH曲线根据缺失程度而受到影响。缺失多达39个氨基酸残基足以消除多巴胺在碱性pH范围内的抑制作用。这些结果表明，多巴胺对酪氨酸羟化酶活性的抑制与该酶N端的氨基酸序列密切相关。
