7-cyano-7-deazaguanine synthase (EC6.3.4.20, preQ0 synthase, 7-cyano-7-carbaguanine synthase, queC (gene)) is an enzyme with systematic name7-carboxy-7-carbaguanine:ammonia ligase (ADP-forming).[1][2] This enzyme catalyses the following chemical reaction
^Cicmil N, Huang RH (August 2008). "Crystal structure of QueC from Bacillus subtilis: an enzyme involved in preQ1 biosynthesis". Proteins. 72 (3): 1084–8. doi:10.1002/prot.22098. PMID18491386.