7c52

Publication Abstract from PubMed

Photosynthetic electron transfers occur through multiple components ranging from small soluble proteins to large integral membrane protein complexes. Co-crystallization of a bacterial photosynthetic electron transfer complex that employs weak hydrophobic interactions was achieved by using high-molar-ratio mixtures of a soluble donor protein (high-potential iron-sulfur protein, HiPIP) with a membrane-embedded acceptor protein (reaction center, RC) at acidic pH. The structure of the co-complex offers a snapshot of a transient bioenergetic event and revealed a molecular basis for thermodynamically unfavorable interprotein electron tunneling. HiPIP binds to the surface of the tetraheme cytochrome subunit in the light-harvesting (LH1) complex-associated RC in close proximity to the low-potential heme-1 group. The binding interface between the two proteins is primarily formed by uncharged residues and is characterized by hydrophobic features. This co-crystal structure provides a model for the detailed study of long-range trans-protein electron tunneling pathways in biological systems.

Crystal structure of a photosynthetic LH1-RC in complex with its electron donor HiPIP.,Kawakami T, Yu LJ, Liang T, Okazaki K, Madigan MT, Kimura Y, Wang-Otomo ZY Nat Commun. 2021 Feb 17;12(1):1104. doi: 10.1038/s41467-021-21397-9. PMID:33597527^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.