4XSL:
reference: X-ray structures of the Pseudomonas cichorii D-tagatose 3-epimerase mutant form C66S recognizing deoxy sugars as substrates., Yoshida H, Yoshihara A, Ishii T, Izumori K, Kamitori S, Appl Microbiol Biotechnol. 2016 Dec;100(24):10403-10415. doi:, 10.1007/s00253-016-7673-7. Epub 2016 Jul 1. PMID: 27368739

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