This article presents a "Proteopedia" page that shows the refined version of the structure of the "Haloarcula" large ribosomal subunit as solved by the laboratories of Thomas Steitz and Peter Moore. The landmark structure is of great impact as it is the first atomic-resolution structure of the highly conserved ribosomal subunit which harbors pep-tide bond-forming activity; it served as the basis for which Thomas Steitz shared the 2009 Nobel Prize in Chemistry with Venkatraman Ramakrishnan and Ada Yonath. The structural data includes 27 proteins and over 3000 nucleotides of RNA.