Identification of d-Erythro-Dihydroneopterin Triphosphate as a Product of Guanosine Triphosphate Cyclohydrolase from Serratia indica |
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| Authors: | Kazuo Iwai Masahiro Kohashi Tsutomu Itadani Tetsuya Suzuki |
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| Institution: | 1. Department of Food Science and Technology, Faculty of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606, Japan;2. Research Institute for Food Science, Kyoto University, Uji, Kyoto 611, Japan |
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| Abstract: | Guanosine triphosphate cyclohydrolase (EC 3.5.4.16) was previously shown to exist in two forms (GTP cyclohydrolase D-I and D-II) in Serratia indica IFO 3759, and they were homogeneously isolated. The present study deals with the characterization of their reaction products. A fluorescent product formed from guanosine triphosphate by GTP cyclohydrolase D-II was identified as 7,8-dihydroneopterin triphosphate by its absorption spectra, phosphate analysis and gas chromatography-mass spectrometry of the dephosphorylated trimethylsilyl derivative. After oxidation and dephosphorylation, the d-erythro configuration of the side chain was made clear by the elution profile on ECTEOLA-cellulose chromatography, Rf values on thin-layer chromatography and by biological activity to Crithidia fasciculata ATCC 12857. The fluorescent products from GTP cyclohydrolase D-I and D-II were indistinguishable. |
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| Keywords: | isoforms kidney bean (Phaseolus vulgaris L ) purification starch branching enzyme |
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