Tissue folylpolyglutamate chain-length characterization by electrophoresis as thymidylate synthetase-fluorodeoxyuridylate ternary complexes.
Tissue folylpolyglutamate chain-length characterization by electrophoresis as thymidylate synthetase-fluorodeoxyuridylate ternary complexes.
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通过电泳表征组织叶酰聚谷氨酸链长作为胸苷酸合成酶-氟脱氧尿苷酸三元复合物。
DOI：
10.1016/0003-2697(81)90540-6
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发表时间：
1981
影响因子：
2.9
通讯作者：
Baugh,CM
中科院分区：
文献类型：
--
作者：
Priest,DG;Happel,KK;Mangum,M;Bednarek,JM;Doig,MT;Baugh,CM
通过将辅因子的5，10-亚甲基四氢叶酸多谷氨酸形式掺入干酪乳杆菌胸苷合成酶和[~3H]氟代脱氧尿酸三元络合物中，估计了组织叶酸多谷氨酸的链长。根据与每个谷氨酸残基的游离羧基功能相关的电荷，对络合物进行电泳法分离。该方法专用于亚甲基四氢叶酸，并确保链长的评估与池平衡或自氧化引入的误差最小。在组织提取物中引入甲醛将四氢叶酸转化为亚甲基衍生物，结果表明两个池具有相同的聚谷氨酸链长。通过这项技术，哺乳动物的肝脏组织被证明含有五谷氨酸翼酯和六谷氨酸翼酯。猴子、猪和兔的肝脏主要含有六谷氨酸，小鼠的肝脏主要含有五谷氨酸，大鼠的肝脏几乎都含有相同比例的六谷氨酸。鸡肝中主要含有五谷氨酸，而鱼肝中主要含有六谷氨酸。干酪乳杆菌中五谷氨酸和六谷氨酸的存在以及酵母中七谷氨酸的存在证实了其他方法早先的观察结果，并证明了这一方法的有效性。
Tissue folate polyglutamate chain lengths have been estimated by incorporation of the 5,10-methylenetetrahydrofolate polyglutamate form of the cofactor into ternary complexes with Lactobacillus casei thymidylate synthetase and [3H]fluorodeoxyuridylate. Complexes were separated electrophoretically on the basis of the charge associated with the free carboxyl function of each glutamate residue. The method is specific for methylenetetrahydrofolate and assures evaluation of chain length with minimal error introduced by pool equilibration or autooxidation. Introduction of formaldehyde into tissue extracts was used to convert tetrahydrofolate to the methylene derivative and show that the two pools have the same polyglutamate chain lengths. By this technique, mammalian liver tissue was shown to contain both pteroylpentaglutamate and pteroylhexaglutamate. Monkey, pig, and rabbit liver contain predominately hexaglutamate, mouse liver predominately pentaglutamate, and rat liver nearly equal proportions of each. Chicken liver contains mostly pentaglutamate and fish liver, hexaglutamate. The presence of penta-and hexaglutamates in L. casei and heptaglutamates in yeast confirms earlier observations by other methods and attests to the validity of this one.