ePrints

Variation in supramolecular organisation of the photosynthetic membrane of Rhodobacter sphaeroides induced by alteration of PufX

Lookup NU author(s): Dr Lucy Crouch

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.

Abstract

In purple bacteria of the genus Rhodobacter (Rba.), an LH1 antenna complex surrounds the photochemical reaction centre (RC) with a PufX protein preventing the LH1 complex from completely encircling the RC. In membranes of Rba. sphaeroides, RC-LH1 complexes associate as dimers which in turn assemble into longer range ordered arrays. The present work uses linear dichroism (LD) and dark-minus-light difference LD (ΔLD) to probe the organisation of genetically altered RC-LH1 complexes in intact membranes. The data support previous proposals that Rba. capsulatus, and Rba. sphaeroides heterologously expressing the PufX protein from Rba. capsulatus, produce monomeric core complexes in membranes that lack long-range order. Similarly, Rba. sphaeroides with a point mutation in the Gly 51 residue of PufX, which is located on the membrane-periplasm interface, assembles mainly non-ordered RC-LH1 complexes that are most likely monomeric. All the Rba. sphaeroides membranes in their ΔLD spectra exhibited a spectral fingerprint of small degree of organisation implying the possibility of ordering influence of LH1, and leading to an important conclusion that PufX itself has no influence on ordering RC-LH1 complexes, as long-range order appears to be induced only through its role of configuring RC-LH1 complexes into dimers. © 2013 Springer Science+Business Media Dordrecht.

Publication metadata

Author(s): Sznee K, Crouch LI, Jones MR, Dekker JP, Frese RN

Publication type: Article

Publication status: Published

Journal: Photosynthesis Research

Year: 2014

Volume: 119

Issue: 1-2

Pages: 243-256

Print publication date: 01/02/2014

Online publication date: 07/11/2013

Acceptance date: 24/10/2013

ISSN (print): 0166-8595

ISSN (electronic): 1573-5079

Publisher: Springer Netherlands

URL: https://doi.org/10.1007/s11120-013-9949-4

DOI: 10.1007/s11120-013-9949-4

PubMed id: 24197265

Altmetrics

Share