1HQK:
reference: X-ray structure analysis and crystallographic refinement of lumazine synthase from the hyperthermophile Aquifex aeolicus at 1.6 A resolution: determinants of thermostability revealed from structural comparisons., Zhang X, Meining W, Fischer M, Bacher A, Ladenstein R, J Mol Biol 2001 Mar 9;306(5):1099-114. PMID: 11237620

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