5B1H:
reference: Crystallographic and mutational analyses of cystathionine beta-synthase in the H2 S-synthetic gene cluster in Lactobacillus plantarum., Matoba Y, Yoshida T, Izuhara-Kihara H, Noda M, Sugiyama M, Protein Sci. 2017 Jan 27. doi: 10.1002/pro.3123. PMID: 28127810

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