This family of proteins participate in the biosynthesis of 7-carboxy-7-deazaguanine. They catalyse the conversion of 7-deaza-7-carboxyguanine to preQ0 [1-3].

1: Identification of four genes necessary for biosynthesis of the modified nucleoside queuosine. Reader JS, Metzgar D, Schimmel P, de Crecy-Lagard V; J Biol Chem. 2004;279:6280-6285. PMID:14660578

2: Genetic analysis identifies a function for the queC (ybaX) gene product at an initial step in the queuosine biosynthetic pathway in Escherichia coli. Gaur R, Varshney U; J Bacteriol. 2005;187:6893-6901. PMID:16199558

3: The deazapurine biosynthetic pathway revealed: in vitro enzymatic synthesis of PreQ(0) from guanosine 5'-triphosphate in four steps. McCarty RM, Somogyi A, Lin G, Jacobsen NE, Bandarian V; Biochemistry. 2009;48:3847-3852. PMID:19354300

4: Crystal structure of QueC from Bacillus subtilis: an enzyme involved in preQ1 biosynthesis. Cicmil N, Huang RH; Proteins. 2008;72:1084-1088. PMID:18491386