Experts and Doctors on azotobacter vinelandii in Irvine, California, United States
Locale: Irvine, California, United States
Topic: azotobacter vinelandii
- Kemper M, Stout C, Lloyd S, Prasad G, Fawcett S, Armstrong F, et al. Y13C Azotobacter vinelandii ferredoxin I. A designed [Fe-S] ligand motif contains a cysteine persulfide. J Biol Chem. 1997;272:15620-7 pubmed..It is interesting to note that neither of the two free cysteines present in FdI was modified. Thus, if NifS is involved in modifying the introduced cysteine there must be specificity to the reaction. ..
- Gao Sheridan H, Pershad H, Armstrong F, Burgess B. Discovery of a novel ferredoxin from Azotobacter vinelandii containing two [4Fe-4S] clusters with widely differing and very negative reduction potentials. J Biol Chem. 1998;273:5514-9 pubmed..In contrast, electrochemical characterization of FdIII clearly establishes that the two [4Fe-4S]2+/+ clusters have very different and highly negative reduction potentials of -486 mV and -644 mV versus the standard hydrogen electrode...
- Gao Sheridan H, Kemper M, Khayat R, Tilley G, Armstrong F, Sridhar V, et al. A T14C variant of Azotobacter vinelandii ferredoxin I undergoes facile [3Fe-4S]0 to [4Fe-4S]2+ conversion in vitro but not in vivo. J Biol Chem. 1998;273:33692-701 pubmed..However, unlike native FdI which does not undergo facile cluster conversion, the 7Fe form T14C FdI quickly converts to the 8Fe form with a high efficiency under reducing conditions. ..
- Chen K, Tilley G, Sridhar V, Prasad G, Stout C, Armstrong F, et al. Alteration of the reduction potential of the [4Fe-4S](2+/+) cluster of Azotobacter vinelandii ferredoxin I. J Biol Chem. 1999;274:36479-87 pubmed..Subsequent Protein Dipole Langevin Dipole calculations (using the actual I40N x-ray structures) did quite accurately predict the observed change in E(0'). ..
- Jung Y, Bonagura C, Tilley G, Gao Sheridan H, Armstrong F, Stout C, et al. Structure of C42D Azotobacter vinelandii FdI. A Cys-X-X-Asp-X-X-Cys motif ligates an air-stable [4Fe-4S]2+/+ cluster. J Biol Chem. 2000;275:36974-83 pubmed..The cluster conversion was ultimately accomplished using a new electrochemical method. Hydrophobic and electrostatic interaction and the lack of Gly residues adjacent to the Asp ligand explain the remarkable stability of this cluster. ..
- Chen K, Jung Y, Bonagura C, Tilley G, Prasad G, Sridhar V, et al. Azotobacter vinelandii ferredoxin I: a sequence and structure comparison approach to alteration of [4Fe-4S]2+/+ reduction potential. J Biol Chem. 2002;277:5603-10 pubmed
- Chen K, Bonagura C, Tilley G, McEvoy J, Jung Y, Armstrong F, et al. Crystal structures of ferredoxin variants exhibiting large changes in [Fe-S] reduction potential. Nat Struct Biol. 2002;9:188-92 pubmed..The smaller (50--100 mV) increases observed for the neutral form are proposed to occur by directing a Hdelta+--Ndelta- dipole toward the reduced form of the cluster. ..
- Swartz L, Kuchinskas M, Li H, Poulos T, Lanzilotta W. Redox-dependent structural changes in the Azotobacter vinelandii bacterioferritin: new insights into the ferroxidase and iron transport mechanism. Biochemistry. 2006;45:4421-8 pubmed..Taken together, these data allow a molecular movie of the ferroxidase gating mechanism to be developed and provide further insight into the iron uptake and/or release and mineralization mechanism of bacterioferritins in general...