6G7G:
reference: Structure of SPH (Self-Incompatibility Protein Homologue) proteins, a widespread family of small, highly stable, secreted proteins., Rajasekar K, Ji S, Coulthard RJ, Ride JP, Reynolds GL, Winn PJ, Wheeler MP, Hyde EI, Smith LJ, Biochem J. 2019 Feb 19. pii: BCJ20180828. doi: 10.1042/BCJ20180828. PMID: 30782970

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