Details of the P-Cluster

Dithionite-reduced P-clusters are diamagnetic and consistent with an all-ferrous state having 5=0. Oxidation of the reduced P-cluster results in iron-sulfur clusters with the following spin identities  

EXAFS data published in 1995 indicate the same contraction in metal-metal distances as the P-cluster is reduced.25 In the thionine-oxidized P2+ form, short Fe-Fe distances are found at 2.74 A in the resting P form, short Fe-Fe distances are around 2.67 A. Long Fe-Fe distances (cross cluster) of approximately 3.75 A 

6-A resolution X-ray crystal structure of Klebsiella pneumoniae MoFe-protein, called Kpl, was solved in 1999 using the coordinates of the 2.2-A Avl 

Name of State Iron Oxidation States [Fe4S4] Core Oxidation State Total Spin 

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