Comparative properties of three pteridine reductases.
Comparative properties of three pteridine reductases.
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三种蝶啶还原酶的比较特性。
DOI：
10.1007/978-1-4615-4735-8_50
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发表时间：
1999
影响因子：
--
通讯作者：
Whiteley,JM
中科院分区：
文献类型：
--
作者：
Chang,CF;Bray,T;Varughese,KI;Whiteley,JM
真核系统中天然存在的蝶啶通常含有2-氨基，4-羟基6-烷基取代基，其由亚甲基-对氨基苯甲酰基谷氨酸酯（或polutamate）或二羟丙基组成。前一类被统称为叶酸，广泛存在于还原和5-烷基化衍生物中，以这种形式参与重要的代谢一碳转移（Blakley，1984）。后者称为生物蝶呤，也以还原形式存在，并且是芳香族氨基酸羟基化至儿茶酚胺途径中的重要辅因子（Shiman，1985;考夫曼和考夫曼，1985; n和Lovenberg，1985）和亚硝酸盐合酶途径中的重要辅因子（Marletta，1993）。二氢叶酸还原酶（DHFR）、二氢蝶啶还原酶（DHPR）和蝶啶还原酶（PTR 1）是利什曼原虫中最具特征的三种酶，它们启动蝶啶与还原的二核苷酸辅因子的还原。它们的比较反应途径如图1所示。
Naturally occurring pteridines in eukaryotic systems usually contain 2-amino, 4-hydroxy 6-alkyl substituents composed of either a methylene-p-aminobenzoylglutamate (or polutamate) or a dihydroxypropyl group. The former class are known collectively as the folates and occur widely as reduced and 5-alkylated derivatives, in which form they participate in important metabolic one-carbon transfers (Blakley, 1984). The latter, known as biopterin,, also occurs in reduced forms and is an important cofactor in aromatic amino acid hydroxylations en route to the catecholamines (Shiman, 1985; Kaufman and Kaufman, 1985; n and Lovenberg, 1985) and in the nitrite synthase pathway (Marletta,, 1993). Dihydrofolate reductase (DHFR), dihydropteridine reductase (DHPR) and pteridine reductase (PTR1), best characterised fromLeishmania, are three enzymes that initiate the reduction of a pteridine in association with a reduced dinucleotide cofactor. Their comparative reaction pathways are illustrated in Figure 1.