Role of Conserved Asn-Tyr-Asp-Tyr Sequence in Bacterial Copper/2,4,5-Trihydroxyphenylalanyl Quinone-containing Histamine Oxidase*
Role of Conserved Asn-Tyr-Asp-Tyr Sequence in Bacterial Copper/2,4,5-Trihydroxyphenylalanyl Quinone-containing Histamine Oxidase*
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保守的 Asn-Tyr-Asp-Tyr 序列在细菌铜/2,4,5-三羟基苯丙氨酰醌含组胺氧化酶中的作用*
DOI：
10.1074/jbc.271.37.22598
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
K. Tanizawa
中科院分区：
文献类型：
--
作者：
Yoon;R. Matsuzaki;Shinnichiro Suzuki;K. Tanizawa
铜胺氧化酶含有共价结合的醌辅因子2，4，5-三羟基苯丙氨酰醌（TPQ），其通过翻译后修饰高度保守序列Asn-Tyr-（Asp/Glu）-Tyr中存在的特定酪氨酰残基合成。为了阐明保守序列在TPQ生物发生中的作用，通过定点诱变将来自球形节杆菌的重组组胺氧化酶中401-404位的每个相应残基用其他氨基酸取代。当Asn-401变为Asp或Gln时，铜依赖性自我加工的TPQ形成速率比野生型酶慢103至104倍。当Tyr-402被Phe取代时，TPQ根本不形成，表明Tyr-402作为TPQ的前体是必需的。与此相反，Asp-403可以被替换为Glu的TPQ形成率没有变化，而其替换为Asn导致显着下降。此外，当Tyr-404变为Phe时，TPQ在与铜离子孵育时迅速形成，但TPQ酶表现出非常低的活性，底物特异性改变。这些结果共同表明，一个非常严格的结构基序是需要有效地形成TPQ和铜胺氧化酶的活性位点的催化活性。
Copper amine oxidase contains a covalently bound quinonoid cofactor, 2,4,5-trihydroxyphenylalanyl quinone (TPQ), which is synthesized by post-translational modification of a specific tyrosyl residue occurring in the highly conserved sequence, Asn-Tyr-(Asp/Glu)-Tyr. To elucidate the role(s) of the conserved sequence in the biogenesis of TPQ, each of the corresponding residues at positions 401-404 in the recombinant histamine oxidase from Arthrobacter globiformis has been replaced with other amino acids by site-directed mutagenesis. When Asn-401 was changed to Asp or Gln, the rate of TPQ formation by copper-dependent self-processing was 103- to 104-fold slower than in the wild-type enzyme. When Tyr-402 was replaced by Phe, TPQ was not formed at all, showing that Tyr-402 is essential as the precursor to TPQ. In contrast, Asp-403 could be replaced by Glu without changes in the rate of TPQ formation, whereas its replacement by Asn led to a marked decrease. Furthermore, when Tyr-404 was changed to Phe, TPQ was formed swiftly on incubation with copper ions, but the TPQ enzyme exhibited very low activity with altered substrate specificity. These results collectively indicate that a very rigorous structural motif is required for efficient formation of TPQ and for the catalytic activity in the active site of copper amine oxidases.
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影响因子：
2.9
作者：
CAI, DY;KLINMAN, JP
通讯作者：
KLINMAN, JP
影响因子：
2.9
作者：
JANES, SM;PALCIC, MM;KLINMAN, JP
通讯作者：
KLINMAN, JP
酵母铜胺氧化酶中 2,4,5-三羟基苯丙氨酸醌生物发生的自催化机制的证据。
DOI：
--
发表时间：
1994
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Cai,D;Klinman,JP
通讯作者：
Klinman,JP
酪氨酸密码子对应于铜胺氧化酶活性位点的托帕醌。
DOI：
--
发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Mu,D;Janes,SM;Smith,AJ;Brown,DE;Dooley,DM;Klinman,JP
通讯作者：
Klinman,JP
影响因子：
2.9
作者：
JANES, SM;KLINMAN, JP
通讯作者：
KLINMAN, JP