7F86

Crystal structure of Phycoerythrin from Halomicronema Sp. R31DM

Summary for 7F86

• Entry DOI: 10.2210/pdb7f86/pdb
• Descriptor: Phycoerythrin beta subunit, Phycoerythrin alpha subunit, PHYCOERYTHROBILIN, ... (4 entities in total)
• Functional Keywords: light harvesting, photosynthesis, phycobiliproteins, cyanobacteria
• Biological source: Halomicronema sp. R31DM; More
• Total number of polymer chains: 24
• Total formula weight: 480859.33

Authors

Patel, S.N.,Gupta, G.D.,Sonani, R.R.,Singh, N.K.,Kumar, V.,Madamwar, D. (deposition date: 2021-07-01, release date: 2022-04-13, Last modification date: 2023-11-29)

Primary citation

Patel, S.N.,Sonani, R.R.,Gupta, G.D.,Singh, N.K.,Kumar, V.,Madamwar, D.
Crystal structure analysis of phycoerythrin from marine cyanobacterium Halomicronema .
J.Biomol.Struct.Dyn., 41:3752-3761, 2023

PubMed Abstract: Phycoerythrin (PE) is green light-absorbing pigment-protein that assists in efficient light harvesting in cyanobacteria and red-algae. PE in cyanobacteria stays less studied so far as compared to that in red algae. In this study, PE from marine cyanobacteria sp. R31DM is purified and subjected for its structural characterisation by X-ray crystallography in order to understand its light-harvesting characteristics. The crystal structure is solved to a resolution-limit of 2.21 Å with reasonable R-factors values, 0.16/0.21 (R/ R). PE forms hexamer of hetero-dimers made up of two peptide chains, α- and β-subunits containing 2 and 3 phycoerythrobilin (PEB) chromophores covalently attached to them, respectively. Geometry of five chromophores is analysed along with their relative position within the PE hexamer. Also, their interactions with the surrounding microenvironment are analysed. The plausible energy transfer pathways in hexamer structure have been predicted based on relative position and geometry of chromophores. This structure enriches the structural information of cyanobacterial PE in order to understand its light-harvesting capacity.Communicated by Ramaswamy H. Sarma.

PubMed: 35354393
DOI: 10.1080/07391102.2022.2055647

Experimental method

X-RAY DIFFRACTION (2.21 Å)