Function (biology)

Chemistry

Bacterial protein

Enzyme

Cell biology

Bacteria

Biology

Genetics

Computational biology

Biochemistry

Nature Chemical Biology

Structural and biochemical studies of the bacterial NAD-decapping enzyme, NudC, in complex with NAD or its cleavage product NMN reveal the critical residues for substrate recognition and the preference of NudC for NAD-capped RNA.                                                                 RNA capping and decapping are thought to be distinctive features of eukaryotes. The redox cofactor NAD was recently discovered to be attached to small regulatory RNAs in bacteria in a cap-like manner, and Nudix hydrolase NudC was found to act as a NAD-decapping enzyme in vitro and in vivo. Here, crystal structures of Escherichia coli NudC in complex with substrate NAD and with cleavage product NMN reveal the catalytic residues lining the binding pocket and principles underlying molecular recognition of substrate and product. Biochemical mutation analysis identifies the conserved Nudix motif as the catalytic center of the enzyme, which needs to be homodimeric, as the catalytic pocket is composed of amino acids from both m...

Structure and function of the bacterial decapping enzyme NudC