A decade of crystallization drops: Crystallization of the cbb3 cytochrome c oxidase from Pseudomonas stutzeri. (4th February 2014)

• Record Type: Journal Article
• Authors: Buschmann, Sabine; Richers, Sebastian; Ermler, Ulrich; Michel, Hartmut
• Is Part Of: Protein science. Volume 23:Number 4(2014:Apr.)
• Page Start: 411
• Page End: 422
• Publication Date: 2014-02-04
• Subjects: Proteins -- Periodicals; 572.6
• DOI: 10.1002/pro.2423
• Languages: English
• ISSNs: 0961-8368

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The <italic>cbb</italic>_{<italic>3</italic>} cytochrome <italic>c</italic> oxidases are distant members of the superfamily of heme copper oxidases. These terminal oxidases couple O₂ reduction with proton transport across the plasma membrane and, as a part of the respiratory chain, contribute to the generation of an electrochemical proton gradient. Compared with other structurally characterized members of the heme copper oxidases, the recently determined <italic>cbb</italic>_{<italic>3</italic>} oxidase structure at 3.2 Å resolution revealed significant differences in the electron supply system, the proton conducting pathways and the coupling of O₂ reduction to proton translocation. In this paper, we present a detailed report on the key steps for structure determination. Improvement of the protein quality was achieved by optimization of the number of lipids attached to the protein as well as the separation of two <italic>cbb</italic>_{<italic>3</italic>} oxidase isoenzymes. The exchange of n‐dodecyl‐β‐<sc>d</sc>‐maltoside for a precisely defined mixture of two α‐maltosides and decanoylsucrose as well as the choice of the crystallization method had a most profound impact on crystal quality. This report highlights problems frequently encountered in membrane protein crystallization and offers meaningful approaches to improve crystal quality.</p> </abstract>