Fig. 4: Intercomplex interactions in the Hlr. halophila LH1–LH2 co-complex.
From: A distinct double-ring LH1–LH2 photocomplex from an extremophilic phototroph
a Schematic illustration of the arrangement of LH1 (closed circles), LH2 polypeptides (open circles), and LH2-B797 (ovals). Color scheme: LH1-α1, green; LH1-β1, blue; LH1-α2, orange; LH1-β2, gray; LH2-α, cyan; LH2-β, magenta; LH2-B797, wheat. The polypeptides surrounded by the dotted line encircle a protomer of the LH1–LH2 complex. b Intercomplex interaction sites (<4.0 Å). All interacting residues are shown as sticks. Most of the intercomplex interactions are hydrophobic and conserved. Non-identical residues of LH1-α are labeled with “*”. Dotted lines indicate hydrogen bonds or ion pairs. c The interface between LH1 and LH2 formed by the LH1 inner ring (α1- and α2-polypeptides) and LH2 outer ring (β-polypeptides). BChls a (LH2-B797) and detergents (DDM) are shown by wheat and cyan sticks, respectively. d Representative intercomplex BChl–BChl distances (Mg–Mg distances in Å) in the LH1–LH2 co-complex. The LH1 and LH2 BChls a are shown in red and wheat, respectively. For clarity, phytol chains are omitted.
