CORRELATION OF GUANOSINE TRIPHOSPHATE CYCLOHYDROLASE ACTIVITY AND SYNTHESIS OF PTERINS IN DROSOPHILA-MELANOGASTER
CORRELATION OF GUANOSINE TRIPHOSPHATE CYCLOHYDROLASE ACTIVITY AND SYNTHESIS OF PTERINS IN DROSOPHILA-MELANOGASTER
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DOI：
10.1007/bf00484766
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发表时间：
1976-01-01
影响因子：
2.4
通讯作者：
BROWN, GM
中科院分区：
文献类型：
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作者：
FAN, CL;HALL, LM;BROWN, GM
GTP环化水解酶是在D.黑腹菌大部分酶（80%）位于成虫的头部。对果蝇发育过程中酶活性的分析显示，在化蛹时存在一个相对较小的活性峰值，而在羽化时出现一个大得多的峰值。酶活性随着果蝇年龄的增长而迅速下降。对果蝇典型蝶啶色素产生的分析表明，在蛹期出现的GTP环化水解酶活性的小峰与异黄蝶呤、蝶呤和sepiapterin的出现相一致，而在羽化期出现的较大峰大致对应于果蝇蝶呤的积累以及大量蝶呤和sepiapterin的出现。在果蝇中，如同在细菌中一样，GTP环化水解酶似乎参与蝶啶的生物合成。对D.黑腹果蝇的研究表明，这些突变体都含有约等于野生型果蝇中发现的量的GTP环化水解酶。这些观察结果不支持Rasmusson等人（1973）提出的zeste是GTP环化水解酶的结构位点的建议。
The enzyme GTP cyclohydrolase, which in bacteria is known to be the 1st enzyme in the biosynthetic pathway for the synthesis of pteridines, was discovered in extracts of D. melanogaster. Most of the enzyme (80%) was located in the head of the adult fly. An analysis of enzyme activity during development in Drosophila revealed the presence of a relatively small peak of activity at pupariation and a much larger peak that appeared at about the time of eclosion. Enzyme activity declined rapidly as the fly aged. Analyses for the production of the typical pteridine pigments of Drosophila indicated that the small peak of GTP cyclohydrolase activity evident at pupariation coincided with the appearance of isoxanthopterin, sepiapterin and pterin, and the larger peak at eclosion roughly corresponded to the accumulation of drosopterin as well as to the appearance in larger amounts of pterin and sepiapterin. In Drosophila, as in bacteria, GTP cyclohydrolase seems to be involved in the biosynthesis of pteridines. Analyses of a variety of zeste mutants of D. melanogaster showed that these mutants all contain GTP cyclohydrolase equal approximately to the amount found in the wild-type fly. These observations do not support the suggestions made by Rasmusson et al. (1973) that zeste is the structural locus for GTP cyclohydrolase.