Fig. 2.

Structure of NocTE. NocTE forms a traditional α/β hydrolase fold observed with NRPS thioesterase domains. a The lid helices α4 and α5 are highlighted in wheat. The catalytic triad residues Ser1790, His1901, and Asp1806 are shown in yellow. In the absence of ligands, the N-terminal portion of helix α4 is disordered. b Catalytic triad residues are highlighted in yellow, while one side-chain orientation of His1808 is shown in cyan. c Superposition of PksA TE (PDB 3ILS) and Srf TE (2VSQ) with NocTE, showing similar lid helix positions. The lid helices of PksA are colored cyan and the helices of SrfA-C are colored green. Loop smoothing is used in (c) for clarity