Identification of a previously uncharacterised polypeptide component of the Rhodopseudomonas palustris light-harvesting 2 complex.

The purple bacterium Rhodopseudomonas palustris is a model organism for dissecting the energy and electron transfer processes that have evolved in phototrophic organisms. This bacterium is of particular interest because, in addition to driving its metabolism via solar energy capture, it is capable of nitrogen and carbon dioxide fixation, producing hydrogen and utilising a wide range of organic compounds. Understanding these processes underpins the potential exploitation of Rhodopseudomonas palustris for synthetic biology, biohydrogen production and bioremediation, for example. Like other purple bacteria, Rhodopseudomonas palustris has 2 light-harvesting (LH) systems: LH1 and LH2. The former has already been extensively characterised by X-ray crystallography and cryo-EM. The aim of this proteomics project is to provide complementary information to support the cryo-EM mapping of LH2 structure.