1NUX:
reference: Metaphosphate in the active site of fructose-1,6-bisphosphatase., Choe JY, Iancu CV, Fromm HJ, Honzatko RB, J Biol Chem 2003 May 2;278(18):16015-20. Epub 2003 Feb 20. PMID: 12595528

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).