4RMP

Crystal structure of allophycocyanin from marine cyanobacterium Phormidium sp. A09DM

4RMP の概要

• エントリーDOI: 10.2210/pdb4rmp/pdb
• 分子名称: Allophycocyanin, PHYCOCYANOBILIN, ... (4 entities in total)
• 機能のキーワード: phycocyanobilin chromophore, globin-like fold (scop, 46457), light harvesting phycobiliprotein, photosynthesis
• 由来する生物種: Phormidium rubidum A09DM; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 36109.08

構造登録者

Kumar, V.,Gupta, G.D.,Sonani, R.R.,Madamwar, D. (登録日: 2014-10-22, 公開日: 2015-05-13, 最終更新日: 2023-09-20)

主引用文献

Sonani, R.R.,Gupta, G.D.,Madamwar, D.,Kumar, V.
Crystal Structure of Allophycocyanin from Marine Cyanobacterium Phormidium sp. A09DM.
Plos One, 10:e0124580-e0124580, 2015

PubMed Abstract: Isolated phycobilisome (PBS) sub-assemblies have been widely subjected to X-ray crystallography analysis to obtain greater insights into the structure-function relationship of this light harvesting complex. Allophycocyanin (APC) is the phycobiliprotein always found in the PBS core complex. Phycocyanobilin (PCB) chromophores, covalently bound to conserved Cys residues of α- and β- subunits of APC, are responsible for solar energy absorption from phycocyanin and for transfer to photosynthetic apparatus. In the known APC structures, heterodimers of α- and β- subunits (known as αβ monomers) assemble as trimer or hexamer. We here for the first time report the crystal structure of APC isolated from a marine cyanobacterium (Phormidium sp. A09DM). The crystal structure has been refined against all the observed data to the resolution of 2.51 Å to Rwork (Rfree) of 0.158 (0.229) with good stereochemistry of the atomic model. The Phormidium protein exists as a trimer of αβ monomers in solution and in crystal lattice. The overall tertiary structures of α- and β- subunits, and trimeric quaternary fold of the Phormidium protein resemble the other known APC structures. Also, configuration and conformation of the two covalently bound PCB chromophores in the marine APC are same as those observed in fresh water cyanobacteria and marine red algae. More hydrophobic residues, however, constitute the environment of the chromophore bound to α-subunit of the Phormidium protein, owing mainly to amino acid substitutions in the marine protein.

PubMed: 25923120
DOI: 10.1371/journal.pone.0124580

実験手法

X-RAY DIFFRACTION (2.506 Å)