Crystal structure of AdoMet radical enzyme 7-carboxy-7-deazaguanine synthase from Escherichia coli suggests how modifications near [4Fe-4S] cluster engender flavodoxin specificity.

ABSTRACT: 7-Carboxy-7-deazaguanine synthase, QueE, catalyzes the radical mediated ring contraction of 6-carboxy-5,6,7,8-tetrahydropterin, forming the characteristic pyrrolopyrimidine core of all 7-deazaguanine natural products. QueE is a member of the S-adenosyl-L-methionine (AdoMet) radical enzyme superfamily, which harnesses the reactivity of radical intermediates to perform challenging chemical reactions. Members of the AdoMet radical enzyme superfamily utilize a canonical binding motif, a CX₃ CXϕC motif, to bind a [4Fe-4S] cluster, and a partial (β/α)₆ TIM barrel fold for the arrangement of AdoMet and substrates for catalysis. Although variations to both the cluster-binding motif and the core fold have been observed, visualization of drastic variations in the structure of Q

SUBMITTER: Grell TAJ 

PROVIDER: S-EPMC6295903 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature