RRC ID 47563
著者 Crouch LI, Jones MR.
タイトル Cross-species investigation of the functions of the Rhodobacter PufX polypeptide and the composition of the RC-LH1 core complex.
ジャーナル Biochim Biophys Acta
Abstract In well-characterised species of the Rhodobacter (Rba.) genus of purple photosynthetic bacteria it is known that the photochemical reaction centre (RC) is intimately-associated with an encircling LH1 antenna pigment protein, and this LH1 antenna is prevented from completely surrounding the RC by a single copy of the PufX protein. In Rba. veldkampii only monomeric RC-LH1 complexes are assembled in the photosynthetic membrane, whereas in Rba. sphaeroides and Rba. blasticus a dimeric form is also assembled in which two RCs are surrounded by an S-shaped LH1 antenna. The present work established that dimeric RC-LH1 complexes can also be isolated from Rba. azotoformans and Rba. changlensis, but not from Rba. capsulatus or Rba. vinaykumarii. The compositions of the monomers and dimers isolated from these four species of Rhodobacter were similar to those of the well-characterised RC-LH1 complexes present in Rba. sphaeroides. Pigment proteins were also isolated from strains of Rba. sphaeroides expressing chimeric RC-LH1 complexes. Replacement of either the Rba. sphaeroides LH1 antenna or PufX with its counterpart from Rba. capsulatus led to a loss of the dimeric form of the RC-LH1 complex, but the monomeric form had a largely unaltered composition, even in strains in which the expression level of LH1 relative to the RC was reduced. The chimeric RC-LH1 complexes were also functional, supporting bacterial growth under photosynthetic conditions. The findings help to tease apart the different functions of PufX in different species of Rhodobacter, and a specific protein structural arrangement that allows PufX to fulfil these three functions is proposed.
巻・号 1817(2)
ページ 336-52
公開日 2012-2-1
DOI 10.1016/j.bbabio.2011.10.009
PII S0005-2728(11)00241-6
PMID 22079525
MeSH Bacterial Proteins / chemistry Bacterial Proteins / genetics Bacterial Proteins / metabolism Bacterial Proteins / physiology* Gene Expression Regulation, Bacterial Light-Harvesting Protein Complexes / chemistry Light-Harvesting Protein Complexes / genetics Light-Harvesting Protein Complexes / metabolism Light-Harvesting Protein Complexes / physiology* Models, Molecular Organisms, Genetically Modified Peptides / chemistry Peptides / metabolism Photosynthesis / genetics Photosynthesis / physiology Photosynthetic Reaction Center Complex Proteins / analysis Photosynthetic Reaction Center Complex Proteins / chemistry Photosynthetic Reaction Center Complex Proteins / metabolism* Photosynthetic Reaction Center Complex Proteins / physiology* Protein Interaction Domains and Motifs Protein Multimerization / genetics Protein Multimerization / physiology Protein Structure, Quaternary Rhodobacter / genetics Rhodobacter / metabolism* Rhodobacter / physiology Rhodobacter capsulatus / genetics Rhodobacter capsulatus / metabolism Rhodobacter capsulatus / physiology Rhodobacter sphaeroides / genetics Rhodobacter sphaeroides / metabolism Rhodobacter sphaeroides / physiology Species Specificity
IF 3.411
引用数 10
WOS 分野 BIOPHYSICS BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
一般微生物 JCM 9340