5VOP:
reference: The folate-binding module of Thermus thermophilus cobalamin-dependent methionine synthase displays a distinct variation of the classical TIM barrel: a TIM barrel with a `twist'., Yamada K, Koutmos M, Acta Crystallogr D Struct Biol. 2018 Jan 1;74(Pt 1):41-51. doi:, 10.1107/S2059798317018290. Epub 2018 Jan 1. PMID: 29372898

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