@article {2268,
	title = {Structural redox control in a 7Fe ferredoxin isolated from Desulfovibrio alaskensis},
	journal = {Bioelectrochemistry},
	volume = {82},
	number = {1},
	year = {2011},
	note = {<p>1878-562X (Electronic)1567-5394 (Linking)Journal ArticleResearch Support, Non-U.S. Gov{\textquoteright}t</p>
},
	month = {Aug},
	pages = {22-8},
	abstract = {<p>The redox behaviour of a ferredoxin (Fd) from Desulfovibrio alaskensis was characterized by electrochemistry. The protein was isolated and purified, and showed to be a tetramer containing one [3Fe-4S] and one [4Fe-4S] centre. This ferredoxin has high homology with FdI from Desulfovibrio vulgaris Miyazaki and Hildenborough and FdIII from Desulfovibrio africanus. From differential pulse voltammetry the following signals were identified: [3Fe-4S](+1/0) (E(0{\textquoteright})=-158+/-5mV); [4Fe-4S](+2/+1) (E(0{\textquoteright})=-474+/-5mV) and [3Fe-4S](0/-2) (E(0{\textquoteright})=-660+/-5mV). The effect of pH on these signals showed that the reduced [3Fe-4S](0) cluster has a pK{\textquoteright}(red)({\textquoteright})=5.1+/-0.1, the [4Fe-4S](+2/+1) centre is pH independent, and the [3Fe-4S](0/-2) reduction is accompanied by the binding of two protons. The ability of the [3Fe-4S](0) cluster to be converted into a new [4Fe-4S] cluster was proven. The redox potential of the original [4Fe-4S] centre showed to be dependent on the formation of the new [4Fe-4S] centre, which results in a positive shift (ca. 70mV) of the redox potential of the original centre. Being most [Fe-S] proteins involved in electron transport processes, the electrochemical characterization of their clusters is essential to understand their biological function. Complementary EPR studies were performed.</p>
},
	keywords = {Bacterial Proteins/*chemistry/isolation \& purification, Desulfovibrio/*chemistry, Electrochemical Techniques, Electron Spin Resonance Spectroscopy, Electron Transport, Ferredoxins/*chemistry/isolation \& purification, Oxidation-Reduction},
	url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve\&db=PubMed\&dopt=Citation\&list_uids=21600857 },
	author = {Grazina, R. and de Sousa, P. M. and Brondino, C. D. and Carepo, M. S. and Moura, I. and Moura, J. J.}
}
