Lipidic sponge phase crystal structure of a photosynthetic reaction center reveals lipids on the protein surface.
Artikel i vetenskaplig tidskrift, 2009

Membrane proteins are embedded in a lipid bilayer and maintain strong interactions with lipid molecules. Tightly bound lipids are responsible for vertical positioning and integration of proteins in the membrane and for assembly of multisubunit complexes and occasionally act as substrates. In this work we present the lipidic sponge phase crystal structure of the reaction center from Blastochloris viridis to 1.86 A, which reveals lipid molecules interacting with the protein surface. A diacylglycerol molecule is bound, through a thioether bond, to the N-terminus of the tetraheme cytochrome c subunit. From the electron density recovered at the Q(B) site and the observed change in recombination kinetics in lipidic sponge phase-grown crystals, the mobile ubiquinone appears to be displaced by a monoolein molecule. A 36 A long electron density feature is observed at the interface of transmembrane helices belonging to the H- and M-subunits, probably arising from an unidentified lipid.

Författare

Annemarie Wöhri

Chalmers, Kemi- och bioteknik, Molekylär mikroskopi

Weixiao Yuan Wahlgren

Göteborgs universitet

Erik Malmerberg

Göteborgs universitet

Linda C Johansson

Göteborgs universitet

Richard Neutze

Göteborgs universitet

Gergely Katona

Göteborgs universitet

Biochemistry

0006-2960 (ISSN) 1520-4995 (eISSN)

Vol. 48 41 9831-8

Ämneskategorier

Kemi

DOI

10.1021/bi900545e

PubMed

19743880