6RWT

Crystal structure of the Cbp3 homolog from Brucella abortus

Summary for 6RWT

• Entry DOI: 10.2210/pdb6rwt/pdb
• Descriptor: Ubiquinol-cytochrome C chaperone, MAGNESIUM ION, ACETATE ION, ... (5 entities in total)
• Functional Keywords: respiratory chain, complex iii, assembly factor, mitochondrial translation, chaperone
• Biological source: Brucella abortus NCTC 8038
• Total number of polymer chains: 1
• Total formula weight: 21109.84

Authors

Masuyer, G.,Ndi, M.,Ott, M.,Stenmark, P. (deposition date: 2019-06-06, release date: 2019-09-18, Last modification date: 2024-05-15)

Primary citation

Ndi, M.,Masuyer, G.,Dawitz, H.,Carlstrom, A.,Michel, M.,Elofsson, A.,Rapp, M.,Stenmark, P.,Ott, M.
Structural basis for the interaction of the chaperone Cbp3 with newly synthesized cytochromebduring mitochondrial respiratory chain assembly.
J.Biol.Chem., 294:16663-16671, 2019

PubMed Abstract: Assembly of the mitochondrial respiratory chain requires the coordinated synthesis of mitochondrial and nuclear encoded subunits, redox co-factor acquisition, and correct joining of the subunits to form functional complexes. The conserved Cbp3-Cbp6 chaperone complex binds newly synthesized cytochrome and supports the ordered acquisition of the heme co-factors. Moreover, it functions as a translational activator by interacting with the mitoribosome. Cbp3 consists of two distinct domains: an N-terminal domain present in mitochondrial Cbp3 homologs and a highly conserved C-terminal domain comprising a ubiquinol-cytochrome chaperone region. Here, we solved the crystal structure of this C-terminal domain from a bacterial homolog at 1.4 Å resolution, revealing a unique all-helical fold. This structure allowed mapping of the interaction sites of yeast Cbp3 with Cbp6 and cytochrome via site-specific photo-cross-linking. We propose that mitochondrial Cbp3 homologs carry an N-terminal extension that positions the conserved C-terminal domain at the ribosomal tunnel exit for an efficient interaction with its substrate, the newly synthesized cytochrome protein.

PubMed: 31537648
DOI: 10.1074/jbc.RA119.010483

Experimental method

X-RAY DIFFRACTION (1.42 Å)