Structure of RC1339/APRc from Rickettsia conorii, a retropepsin‐like aspartic protease. (1st October 2015)

• Record Type: Journal Article
• Authors: Li, Mi; Gustchina, Alla; Cruz, Rui; Simões, Marisa; Curto, Pedro; Martinez, Juan; Faro, Carlos; Simões, Isaura; Wlodawer, Alexander
• Is Part Of: Acta crystallographica. Volume 71:Part 10(2015:Oct.)
• Page Start: 2109
• Page End: 2118
• Publication Date: 2015-10-01
• Subjects: Biomolecules -- Structure -- Periodicals; Physical biochemistry -- Periodicals; X-ray crystallography -- Periodicals; Crystallography -- Periodicals; 572
• DOI: 10.1107/S1399004715013905
• Languages: English
• ISSNs: 0907-4449

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The crystal structures of two constructs of RC1339/APRc from <italic>Rickettsia conorii</italic>, consisting of either residues 105–231 or 110–231 followed by a His tag, have been determined in three different crystal forms. As predicted, the fold of a monomer of APRc resembles one‐half of the mandatory homodimer of retroviral pepsin‐like aspartic proteases (retropepsins), but the quaternary structure of the dimer of APRc differs from that of the canonical retropepsins. The observed dimer is most likely an artifact of the expression and/or crystallization conditions since it cannot support the previously reported enzymatic activity of this bacterial aspartic protease. However, the fold of the core of each monomer is very closely related to the fold of retropepsins from a variety of retroviruses and to a single domain of pepsin‐like eukaryotic enzymes, and may represent a putative common ancestor of monomeric and dimeric aspartic proteases.</p> </abstract>