2LQA:
reference: Asteropsin A: An unusual cystine-crosslinked peptide from porifera enhances neuronal Ca(2+) influx., Li H, Bowling JJ, Fronczek FR, Hong J, Jabba SV, Murray TF, Ha NC, Hamann MT, Jung JH, Biochim Biophys Acta. 2012 Nov 29;1830(3):2591-2599. doi:, 10.1016/j.bbagen.2012.11.015. PMID: 23201194

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