1doy
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1H AND 15N SEQUENTIAL ASSIGNMENT, SECONDARY STRUCTURE AND TERTIARY FOLD OF [2FE-2S] FERREDOXIN FROM SYNECHOCYSTIS SP. PCC 6803
OverviewOverview
The [2Fe-2S] ferredoxin extracted from Synechocystis sp. PCC 6803 was studied by 1H and 15N nuclear magnetic resonance. Sequence-specific 1H and 15N assignment of amino acid residues far from the paramagnetic cluster (distance higher than 8 A) was performed. Interresidue NOE constraints have allowed the identification of several secondary structure elements: one beta sheet composed of four beta strands, one alpha helix, and two alpha helix turns. The analysis of interresidue NOEs suggests the existence of a disulfide bridge between the cysteine residues 18 and 85. Such a disulfide bridge has never been observed in plant-type ferredoxins. Structure modeling using the X-PLOR program was performed with or without assuming the existence of a disulfide bridge. As a result, two structure families were obtained with rms deviations of 2.2 A. Due to the lack of NOE connectivities resulting from the paramagnetic effect from the [2Fe-2S] cluster, the structures were not well resolved in the region surrounding the [2Fe-2S] cluster, at both extremities of the alpha helix and the C and N terminus segments. In contrast, when taken separately, the beta sheet and the alpha helix were well defined. This work is the first report of a structure model of a plant-type [2Fe-2S] Fd in solution.
About this StructureAbout this Structure
1DOY is a Single protein structure of sequence from Synechocystis sp. with as ligand. Full crystallographic information is available from OCA.
ReferenceReference
1H and 15N NMR sequential assignment, secondary structure, and tertiary fold of [2Fe-2S] ferredoxin from Synechocystis sp. PCC 6803., Lelong C, Setif P, Bottin H, Andre F, Neumann JM, Biochemistry. 1995 Nov 7;34(44):14462-73. PMID:7578051
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