6JPR

Crystal structure of Phycocyanin from Nostoc sp. R76DM

6JPR の概要

• エントリーDOI: 10.2210/pdb6jpr/pdb
• 分子名称: Phycocyanin, PHYCOCYANOBILIN, SODIUM ION, ... (6 entities in total)
• 機能のキーワード: cyanobacteria, phycobiliprotein, light harvesting, phycocyanobilin, photosynthesis
• 由来する生物種: Nostoc; 詳細
• タンパク質・核酸の鎖数: 12
• 化学式量合計: 226315.47

構造登録者

Sonani, R.R.,Gupta, G.D.,Rastogi, R.P.,Patel, S.N.,Madamwar, D.,Kumar, V. (登録日: 2019-03-27, 公開日: 2019-06-26, 最終更新日: 2023-11-22)

主引用文献

Sonani, R.R.,Rastogi, R.P.,Patel, S.N.,Chaubey, M.G.,Singh, N.K.,Gupta, G.D.,Kumar, V.,Madamwar, D.
Phylogenetic and crystallographic analysis of Nostoc phycocyanin having blue-shifted spectral properties.
Sci Rep, 9:9863-9863, 2019

PubMed Abstract: The distinct sequence feature and spectral blue-shift (~10 nm) of phycocyanin, isolated from Nostoc sp. R76DM (N-PC), were investigated by phylogenetic and crystallographic analyses. Twelve conserved substitutions in N-PC sequence were found distributed unequally among α- and β-subunit (3 in α- and 9 in β-subunit). The phylogenetic analysis suggested that molecular evolution of α- and β-subunit of Nostoc-phycocyanin is faster than evolution of Nostoc-species. The divergence events seem to have occurred more frequently in β-subunit, compared to α-subunit (relative divergence, 7.38 for α-subunit and 9.66 for β-subunit). Crystal structure of N-PC was solved at 2.35 Å resolution to reasonable R-factors (R/R = 0.199/0.248). Substitutions congregate near interface of two αβ-monomer in N-PC trimer and are of compensatory nature. Six of the substitutions in β-subunit may be involved in maintaining topology of β-subunit, one in inter-monomer interaction and one in interaction with linker-protein. The β153Cys-attached chromophore adopts high-energy conformational state resulting due to reduced coplanarity of B- and C-pyrrole rings. Distortion in chromophore conformation can result in blue-shift in N-PC spectral properties. N-PC showed significant in-vitro and in-vivo antioxidant activity comparable with other phycocyanin. Since Nostoc-species constitute a distinct phylogenetic clade, the present structure would provide a better template to build a model for phycocyanins of these species.

PubMed: 31285455
DOI: 10.1038/s41598-019-46288-4

実験手法

X-RAY DIFFRACTION (2.35 Å)