Crystallization and preliminary X-ray characterization of queD from Bacillus subtilis, an enzyme involved in queuosine biosynthesis. Acta Crystallogr. Sect. Identification; Name: 6-carboxy-5,6,7,8-tetrahydropterin synthase: Synonyms: CPH4 synthase; Queuosine biosynthesis protein queD; Gene Name: queD: Enzyme Class: QueD (previously named ykvK) is one of several enzymes involved in the biosynthesis of the hypermodified nucleoside queuosine. Queuosine is incorporated into tRNA at. Queuosine biosynthesis protein QueD Gene names i: Name:queD. Synonyms: ygcM. Ordered Locus Names: SF2781, S2974. Organism i: Shigella flexneri: Taxonomic identifier i. QueD (previously named ykvK) is one of several enzymes involved in the biosynthesis of the hypermodified nucleoside queuosine. Queuosine is incorporated into tRNA at. Crystallization and preliminary X-ray characterization of the nitrile reductase QueF: a queuosine-biosynthesis enzyme Biosynthesis of the deazapurines toyocamycin and queuosine begins with the conversion of GTP to H 2 NTP by GCH I. The remaining steps leading to the central precursor. Since GTP cyclohydrolase activity had been implicated in queuosine biosynthesis as. the essential genes for the biosynthesis of queuosine, queC, queD. Crystallization and preliminary X-ray characterization of queD from Bacillus subtilis, an enzyme involved in queuosine biosynthesis Escherichia coli QueD is a 6-carboxy-5,6,7,8-tetrahydropterin synthase. homologue possibly involved in queuosine biosynthesis.