1JLS:
reference: The structural mechanism of GTP stabilized oligomerization and catalytic activation of the Toxoplasma gondii uracil phosphoribosyltransferase., Schumacher MA, Bashor CJ, Song MH, Otsu K, Zhu S, Parry RJ, Ullman B, Brennan RG, Proc Natl Acad Sci U S A 2002 Jan 8;99(1):78-83. PMID: 11773618

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