4ZRS:
reference: Enhancing the Thermostability of Feruloyl Esterase EstF27 by Directed Evolution and the Underlying Structural Basis., Cao LC, Chen R, Xie W, Liu YH, J Agric Food Chem. 2015 Sep 23;63(37):8225-33. doi: 10.1021/acs.jafc.5b03424., Epub 2015 Sep 10. PMID: 26329893

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