Armstrong, George

Armstrong, F.A., George, S.J., Thomson, A.J., and Yates, M.G. (1988) Direct electrochemistry in the characterization of redox proteins-novel properties of Azobacter 7Fe ferredoxin. FEES Letters, 234 (1), 107-110. 

Caldemeyer KS, Pascuzzi RM, Moran CC, et al Toluene abuse causing reduced MR signal intensity in the brain. American Journal of Radiology 161 1259-1261,1993 Caldemeyer KS, Armstrong SW, George KK, et al The spectrum of neuroimaging abnormalities in solvent abuse and their clinical correlation. J Neuroimaging 6 167-173, 1996... 

In the United States of the late 1800s, wild-West shows were popular, buffalo herds free-ranged, and George Armstrong Custer, fighting the Sioux, made his famous last stand. In 1861 Yale granted its first Ph.D. 

In a similar manner it has proved easy to demonstrate and study the stoichiometrie incorporation of Zn ", Co and Cd " to produce clusters with characteristic electrochemical and spectroscopic properties (Armstrong FA, Butt JN, George SJ, Hatchikian EC, Thomson AJ, unpublished results). Reduetion potentials deerease in the order [Co-3Fe-4S] (approx. — 300mV)> [4Fe-4S] (approx. - 390 mV) > [Zn-3Fe-4S] (approx. — 480 mV) > [Cd 3Fe-4S] (approx. — 580 mV). In each of these cases, metal-ion uptake into [3Fe-4S] was very rapid. Incorporation into the oxidized (1 -I-) cluster was not observed. 

Cys-X-X-Asp-X-X-Cys sequence (Fig. 19) shows stable cyclic voltammetry in the presence of 0.1 raM Fe even at 60 °C (Armstrong FA, Butt JN, Cammack R, George SJ, Thomson AJ, unpublished results). Clearly in this case, the ability of [3Fe-4S]° to accept the fourth Fe is greatly diminished. Factors that may be influential include active-site exposure Sulfolobus Fd is much larger) and, perhaps, the presence, in D.a. Fdlll of a Glu instead of the usual Pro residue adjacent to the remote Cys coordinating the transformable cluster. Proline is well known as a creator of kinks or bends in the polypeptide chain. 

Armstrong FA, George SJ, Thomson AJ, Yates MG (1988) FEBS Lett. 234 107... 

Armstrong FA, George SJ, Cammack R, Hatchikian EC, Thomson AJ Biochem. J. 

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