Properties of the detergent solubilised cytochrome c oxidase (cytochrome cbb 3) purified from Pseudomonas stutzeri

[摘要]

Cytochrome cbb ₃ is a cytochrome c-oxidising isoenzyme that belongs to the superfamily of respiratory haem/copper oxidases. We have developed a purification method yielding large amounts of pure cbb ₃ complex from the soil bacterium Pseudomonas stutzeri. This cytochrome cbb ₃ complex consists of three subunits (ccoNOP) in a 1:1:1 stoichiometry and contains two b-type and three c-type haems. The protein complex behaves as a monomer with an overall molecular weight of 114.0±8.9 kDa and a s ⁰ _20,w value of 8.9±0.3 S as determined by analytical ultracentrifugation. Crystals diffracting to 5.0 Å resolution have been grown by the vapour diffusion sitting drop method to an average size of 0.1×0.1×0.3 mm. This is the first crystallisation report of a (cbb ₃)-type oxidase.

[学科分类] 生物化学/生物物理

[关键词] Cytochrome oxidase;Membrane protein;Crystallography;Analytical ultracentrifugation;Mass spectrometry;Pseudomonas;DM;n-dodecyl-β-D-maltoside;TMPD;N;N;N′;N′-tetramethyl-p-phenyldiamine;TMBZ;3;3′;5;5′-tetramethylbenzidine;TFA;trifluoroacetic acid;1 S;1×10−13 s/rad−2