Effect of formate on Mössbauer parameters of the non‐heme iron of PS II particles of cyanobacteria

FEBS Letters

Novakova, A.A.¹  Semin, B.K.¹  Loviagina, E.R.¹  Aleksandrov, A.Yu.¹  Kaurov, Yu.N.¹ 

[1] Department of Biophysics, Faculty of Biology, University of Moscow, Moscow 119899, USSR

关键词: Photosystem II;    Non-heme iron;    Bicarbonate;    Mössbauer spectroscopy;   

DOI  :  10.1016/0014-5793(90)81263-N

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Mössbauer spectra were measured for PSII particles having an active water-splitting system. The particles were isolated from the thennophilic cyanobacterium Synechococcus elongatus enriched in⁵⁷Fe. The Mössbauer resonance absorption spectrum is a superposition of 3 doublets with the following quadrupole splitting and chemical shift: 1, δ = 0.40, Δ = 0.85; II, δ = 1.35,Δ =2.35; III, δ = 0.25, Δ = 1.65. The δ and Δ values of doublets I, II, III are characteristic of proteins with iron-sulphur center, non-heme iron of the reaction center of higher plants and of the oxidized cytochrome 6–559. Treatment with sodium formate to remove bicarbonate affects only the doublet of non-heme iron, causing its quadrupole splitting to reduce to 1.75 and the chemical shift to reduce to 0.90. After washing out the formate, the Mossbauer spectrum of non-heme iron is restored. The data suggest that bicarbonate is a ligand for the non-heme iron of the reaction center of cyanobacteria.

【 授权许可】

Unknown