title: Formation of beta,gamma-methylene-7,8-dihydroneopterin 3'-triphosphate from beta,gamma-methyleneguanosine 5'-triphosphate by GTP cyclohydrolase I of Escherichia coli.
abstract: GTP cyclohydrolase I of Escherichia coli converts [beta,gamma-methylene] GTP to a fluorescent product that is characterized as [beta,gamma-methylene]dihydroneopterin triphosphate. Interaction between the GTP analog and the enzyme gave a Ki of 3.0 microM, which may be compared to the Km of 0.1 microM for GTP. This new analog of dihydroneopterin triphosphate may, in turn, be converted to the same greenish-yellow pteridines (compounds X, X1, and X2) that are obtained from dihydroneopterin triphosphate. Because of its stability to phosphatase action, this analog may be useful for studies in pteridine metabolism.
mesh_terms: D000619:Aminohydrolases / Q000378:metabolism*; D055598:Chemical Phenomena; D002621:Chemistry; D002845:Chromatography / Q000379:methods; D004926:Escherichia coli / Q000201:enzymology*; D006136:GTP Cyclohydrolase / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D019798:Neopterin / Q000031:analogs & derivatives; D011621:Pteridines / Q000096:biosynthesis*; D013050:Spectrometry, Fluorescence; D013379:Substrate Specificity
chemical_list: D011621:Pteridines; C011265:guanosine 5'-(beta,gamma-methylene)triphosphate; D019798:Neopterin; D006160:Guanosine Triphosphate; C042684:beta,gamma-methylene-7,8-dihydroneopterin 3'-triphosphate; D000619:Aminohydrolases; D006136:GTP Cyclohydrolase