3BL8:
reference: Crystal structure of the extracellular cholinesterase-like domain from neuroligin-2., Koehnke J, Jin X, Budreck EC, Posy S, Scheiffele P, Honig B, Shapiro L, Proc Natl Acad Sci U S A. 2008 Feb 12;105(6):1873-8. Epub 2008 Feb 4. PMID: 18250328

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