5NFG:
reference: Functional and structural characterization of synthetic cardosin B-derived rennet., Almeida CM, Manso JA, Figueiredo AC, Antunes L, Cruz R, Manadas B, Bur D, Pereira PJB, Faro C, Simoes I, Appl Microbiol Biotechnol. 2017 Aug 2. doi: 10.1007/s00253-017-8445-8. PMID: 28770303

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