Dennis Dean

EDUCATION

Ph.D. Molecular Biology 1979 Purdue University, West Lafayette, Indiana 

Bachelor of Arts 1973 Wabash College, Crawfordsville, Indiana

 

EMPLOYMENT/APPOINTMENTS

2008-present: Director, Fralin Life Science Institute

2008-2010: Director, Virgina Tech Carilion Research Institute

2006-2008: Term Director, Institute for Biomedical & Public Health Sciences

2002-2008: Director, Fralin Biotechnology Center

1995-2002: Associate Director, Fralin Biotechnology Center

1994-present: Professor, Department of Biochemistry

1988-1994: Associate Professor, Department of Anaerobic Microbiology

1985-1988: Assistant Professor, Department of Anaerobic Microbiology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia

1982-1985: Staff Scientist, Charles F. Kettering Research Laboratory, Yellow Springs, Ohio

 

 

FELLOWSHIPS

1984: NATO Fellow, Nitrogen Fixation Unit -Sussex, AFRC, United Kingdom

1979-1982: NIH Post-doctoral Fellow, Enzyme Institute, University of Wisconsin, Madison

1975-1979: NIH Pre-doctoral Fellow, Purdue University

 

 

AWARDS

2007-present: University Distinguished Professor, Stroobants Professor of Biotechnology

2005-2010: College of Agriculture Distinguished Research Scientist

 

 

TEACHING ASSIGNMENTS

General Microbiology, Prokaryotic Gene Expression, Undergraduate Honors Research Colloquium in Molecular Microbiology 

 

INVITED LECTURES/INTERNATIONAL CONFERENCES

ICN-UCLA Symposium on Molecular Genetics and Cellular Biology, 1977 International Conference on Translational Control, 1981 Gordon Research Conference (Gene Regulation), 1981 Gordon Research Conference (Nitrogen Fixation), 1994, 1996, 1998, 2000, 2002, 2004 Gordon Research Conference (Photosynthesis, 1999 Gordon Research Conference (Quinone and Redox-Active Amino Acid Cofactors), 2002 Gordon Research Conference (Proteins), 1995 Gordon Research Conference (Microbial Stress), 1996 Gordon Research Conference (Metals in Biology), 1993, 2001, 2003 Gordon Research Conference (Enzymes, Co-enzymes & Cofactors), 2005 Gordon Research Conference (Iron-Sulfur Proteins), 2006, 2008, 2010 Gordon Research Conference (Metals in Cell Biology) 2009 Agouron Conference on Nitrogen 2009, American Society for Microbiology IMAGE conference 2007. National Meeting for the American Society for Biological Chemists, 1981 7th, 8th, 9th, 11th, 12th, and 13th International Congress on Nitrogen Fixation, 1988, 1990, 1992, 1997, 1999, 2001 International Congress on Plant Molecular Biology 1991 National Meeting of the American Society for Microbiology 1991, 1999, 2000, 2001, 2002 National Meeting of the American Chemical Society 1992, 2009, AAAS National Meeting 1993 International Congress on Bioinorganic Chemistry 1995, 1999, 2005. International Congress on Bioiron 1995, 2003, International Congress on PLP enzymes 1994 1st, 2nd, 5th, 6th 7th 8th 9th European Conferences on Nitrogen Fixation 1994, 1996, 2000, 2002, 2004, 2006, 2008 Steenbock Symposium on Biosynthesis and Functions of Metalloenzymes 1997 Steenbock Symposium on Iron Sulfur Proteins 2005, Penn State Symposium on Novel Enzymes 1997, 2010 International Conference on Iron Sulfur proteins 2002, 2004, 2007, 2009. Biometals 2002 Enzyme Mechanisms 2002, Dalton Discussion IV 2002 Endosymbiosis 2009 Symposium on Metalloproteins, University of Utah 2004, International Conference on Hydrogenases 1998, 2004, 2007. London Frataxin Meeting 2010 

 

PROFESSIONAL SERVICE

Co-Chair Gordon Research Conference (Nitrogen Fixation) 1996, 1998 Panel member USDA-CRGO Nitrogen Fixation Program 1988, 1993, 1994, 2004, 2007 Panel manager USDA-CRGO Nitrogen Fixation Program 1995 Panel member Nitrogen Fixation Review for DOE Biosciences Research Program 1993 Panel member DOE Biosciences Research Program 1995 Member NIH Microbial Physiology study section 1997 Instructor University of Georgia Inorganic Biochemistry Summer Workshop 1994-2000 Member Editorial Board Journal of Bacteriology 1993-2010 Panel Member National Science Foundation (Biochemistry) 1996-2003, 2006, 2009 Panel Member National Science Foundation (Prokaryotic Biology) 2003-2008 Panel Member National Science Foundation (IGERT) 2007 Panel Member National Science Foundation (SMP) 2010 Panel Member Naational Science Foundation (S-STEM) 2010 Member Editorial Board, Journal of Biological Chemistry 2001-2012 Member (by election) Publications Board, American Society for Biochemistry & Mol. Biol. 2006-2009 

 

PROFESSIONAL MEMBERSHIPS

American Chemical Society, American Society for the Advancement of Science, American Society for Microbiology, American Society for Biochemistry and Molecular Biology, Society for Bioinorganic Chemistry

 

POST-DOCTORAL TRAINEES (10 Total)

Marty Jacobson, Lisa Martin, Limin Zheng, Jason Christianson, Suzanne Mayer, Jeverson Frazzon, Mihaela Unciuleac, Patricia Dos Santos, Ana Frazzon, Jaim Simoes de Oliviera.

 

DISSERTATIONS DIRECTED (13 Total)

Kevin Brigle (Ph.D.), Paul Goodwin (Ph.D.), Pramvadee Yuvaniyama (Ph.D), John Peters (Ph.D), Richard Jack (Ph.D.) Robert Setterquist (M.S.), Leonard Comaratta (M.S.), Lisa Bennett (M.S.), Mark Wilson (M.S), Patricia Dos Santos (Ph.D.), Deborah Johnson (Ph.D.); Estella Raulfs (Ph.D), Ina Puleri (Ph.D).

 

UNDERGRADUATE RESEARCH TRAINEES (46 Total)

Sheila Van Meter, Claudia Vigil, Myke'lle Hertsgaard, Jennifer Zallen, Lisa Remaklus, Stacey Zell, Christopher Chang, Brett Dunn, Britt East, Christina O'Kernick, Mark Harpin, Amr Ragab, Chad Williamson, Greg Polsinelli, Eugene Reilly, Joseph Baus, Jennifer Fick, Jennifer Riordon, Dave Mallard, Jocelyn Kuzelka, Sarah Baas, Tony diNicola, Steve Richmond, Matthew Teletic, John White, Adrian Cubbage, Katherine Padget, Eume Jung, Milagros Perez, Brook Ragle, Tamara Davis, Melissa dela Cuesta, Lauren Stone, Kyle Zingaro, Charles Bressan, Matthew Solomon, Lanessa Brandt, Deise Galan, Jennifer Downs, Sachi Desai, Kyle Cromer, Lydia Choi, Coryne Hosmer, Kerri Martin, Luisa de Oliviera, Alec Good. 

 

REFEREED PUBLICATIONS

Book Chapters:

1. Dean, D., and M. Nomura. 1982. Organization and regulation of expression of ribosomal protein genes. In G. Rothblum and H. Busch (eds.), The Cell Nucleus, Vol. XII. Academic Press. pp. 186-209.

2. Nomura, M., D. R. Dean, and J. L. Yates. 1983. Feedback regulation of ribosomal protein synthesis in Escherichia coli. In Hunt, Prentis, and Tooze (eds.), DNA makes RNA Protein. Elsevier Biomedical Press. pp. 240-245.

3. Kennedy, S., R. Robson, R. Jones, P. Woodley, D. Evans, P. Bishop, R. Eady, R. Gamal, R. Humphrey, J. Ramos, D. Dean, K. Brigle, A. Toukdarian, and J. Postgate. 1985. Genetic and physical characterization of nif and ntr genes in Azotobacter chroococcum and Azotobacter vinelandii. In H. J. Evans, P. J. Bottomley, and W. E. Newton (eds.), Current plant science and biotechnology in agriculture: Nitrogen fixation research process. Martinus Nijhoff. pp. 469-476.

4. Dean, D. R., K. E. Brigle, H. D. May, and W. E. Newton. 1988. Site-directed mutagenesis of the nitrogenase MoFe protein. In H. Bothe, F. J. deBruijn, and W. E. Newton (eds.), Nitrogen Fixation: Hundred Years After. Gustav Fischer. pp. 107-113.

5. Hinton, S. M., and D. R. Dean. 1990. Biogenesis of Molybdenum cofactors. Critical Reviews in Microbiology. CRC Press. Vol. 17, pp. 169-188.

6. Dean, D. R., D. J. Scott, and W. E. Newton. 1990. Identification of FeMoco domains within the nitrogenase MoFe protein. In P. M. Gresshoff, L. E. Roth, G. Stacey, and W. E. Newton (eds.), Nitrogen Fixation: Achievements and Objectives. Chapmann and Hall. pp. 95-102.

7. Dean, D. R., and M. R. Jacobson. 1992. Biochemical Genetics of Nitrogenase. In G. Stacey, R. H. Burris, and H. J. Evans (eds.), Biological Nitrogen Fixation. Chapmann and Hall. pp. 763-834.

8. Kim, C.-H., L. Zheng, W. E. Newton, and D. R. Dean. 1992. Intermolecular electron transfer and substrate reduction properties of MoFe proteins altered by site-specific amino acid substitution. In R. Palacios, J. Mora, and W.E. Newton (eds.), New Horizons in Nitrogen Fixation. Kluwer Academic Publishers. pp.105-110.

9. Newton, W. E., and D. R. Dean. 1993. Role of the iron-molybdenum cofactor polypeptide environment in Azotobacter vinelandii molybdenum-nitrogenase catalysis. Molybdenum enzymes, cofactors, and model systems. American Chemical Society. Vol. 535, pp.216-230.

10. Zheng L., and D. R. Dean. 1994. Involvement of PLP in biological formation iron-sulphur clusters. Biochemistry of Vitamin B6 and PQQ. Birkhäuser Verlag Basel/Switzerland. pp. 211-215.

11. Muchmore, S. W., R. F. Jack, and D. R. Dean. 1995. Developments in the analysis of nitrogenase FeMo-cofactor biosynthesis. Advances in Inorganic Biochemistry. Vol. 11. pp. 111-133.

12. Dean, D. R., J. Christiansen, P. Yuvaniyama, L. Zheng, V. Cash, J. Agar, M. K. Johnson, and D. R. Dean. 1998. Activation of iron and sulfur for nitrogenase metallocluster formation. Biological Nitrogen Fixation for the 21st Century. Kluwer Academic Publishers. pp 27-31.

13. Christiansen, J. and D. R. Dean. 1999. Nitrogen Fixation. Encyclopedia of Molecular Biology. Vols. 1-4, pp. 1617-1623.

14. Christiansen, J., J. M. Chan, L. C. Seefeldt, and D. R. Dean. 2000. Use of amino acid substitutions to study the functional properties of the nitrogenase MoFe protein. Prokaryotic Nitrogen Fixation: A Model System for Analysis of a Biological Process. Horizon Scientific Press.

15. Frazzon, J. and D. R. Dean. 2002. Biosynthesis of the nitrogenase iron-molybdenum-cofactor from Azotobacter vinelandii. Metal ions in biological systems. Marcel Dekker. Vol. 39. pp. 163-186.

16. Mayer, S. M., P. Dos Santos, L. C. Seefeldt, and D. R. Dean. 2002. Use of short-chain alkynes to locate the nitrogenase catalytic site. Nitrogen Fixation at the Millenium. Elsevier Science. pp. 137-154.

17. Agar, J. N., D. R. Dean, and M. K. Johnson. 2003. Iron-sulfur cluster biosynthesis. Biochemistry and Physiology of Anaerobic Bacteria. Springer-Verlag. pp. 46-66.

18. Lee, H.-I., L. M. Cameron, J. Christiansen, P. D. Christie, R. C. Pollock, R. Song, M. Srlie, W. H. Orme-Johnson, D. R. Dean, B. J. Hales, and B. M. Hoffman. 2003. Q-band ENDOR studies of the nitrogenase MoFe protein under turnover conditions: Substrate-inhibitor-binding to and metal-ion valencies of the FeMo-cofactor. Paramagnetic Resonance of Metallobiomolecules. ACS Symposium Series 858. pp. 150-178.

19. Mayer, S. M., P. C. Dos Santos, L. C. Seefeldt, and D. R. Dean. 2004. Strategies for the functional analysis of the Azotobacter vinelandii MoFe protein and its active site FeMo-cofactor. Catalysts for nitrogen fixation: Nitrogenases, relevant chemical models, and commercial processes. Kluwer Academic Publishers. pp. 141-159.

 

JOURNAL ARTICLES

20. Dean, D. R., J. A. Hoch, and A. I. Aronson. 1977. Alteration of the Bacillus subtilis glutamine synthetase results in overproduction of the enzyme. J. Bacteriol. 131: 98-987.

21. Dean, D. R., and A. I. Aronson. 1980. Selection of Bacillus subtilis mutants impaired in ammonia assimilation. J. Bacteriol. 141: 985-987.

22. Dean, D. R., and M. Nomura. 1980. Feedback regulation of ribosomal protein gene expression in Escherichia coli. Proc. Natl. Acad. Sci. USA 77: 3590-3594.

23. Nomura, M., J. L. Yates, D. R. Dean, and L. E. Post. 1980. Feedback regulation of ribosomal protein gene expression in Escherichia coli: Structural homology of ribosomal RNA and ribosomal protein mRNA. Proc. Natl. Acad. Sci. USA 77: 7084-7088.

24. Dean, D. 1981. A plasmid cloning vector for the direct selection of strains carrying recombinant plasmids. Gene 15: 99-102.

25. Dean, D., J. L. Yates, and M. Nomura. 1981. Escherichia coli ribosomal protein S8 feedback regulates part of the spc operon. Nature (London) 289: 89-91.

26. Dean, D., J. L. Yates, and M. Nomura. 1981. Identification of ribosomal protein S7 as a repressor of translation within the str operon of E. coli. Cell 24: 413-419.

27. Yates, J. L., D. Dean, W. A. Strycharz, and M. Nomura. 1981. E. coli ribosomal protein L10 inhibits translation of L10 and L7/L12 mRNAs by acting at a single site. Nature (London) 294: 190-192.

28. Lamb, D. H., D. R. Dean, and A. I. Aronson. 1982. A high frequency of Bacillus subtilis glutamine auxotrophs revert to cold sensitivity. J. Gen. Microbiol. 128: 671-678.

29. Nomura, M., D. Dean, and J. L. Yates. 1982. Feedback regulation of ribosomal protein synthesis in Escherichia coli. Trends in Biochemical Sciences 7: 92-97.

30. Cerretti, D. P., D. R. Dean, G. R. Davis, D. M. Bedwell, and M. Nomura. 1983. The spc ribosomal protein operon of Escherichia coli: Sequence and cotranscription of the ribosomal protein genes and a protein export gene. Nucleic Acids Research 11: 2599-2616.

31. Brigle, K. E., W. E. Newton, and D. R. Dean. 1985. Complete nucleotide sequence of the Azotobacter vinelandii nitrogenase structural gene cluster. Gene 37: 37-44.

32. Dean, D. R., and K. E. Brigle. 1985. Azotobacter vinelandii nifD- and nifE-encoded polypeptides share structural homology. Proc. Natl. Acad. Sci. USA 82: 5720-5723.

33. Bishop, P. E., R. Premakamur, D. R. Dean, M. R. Jacobson, J. R. Chisnell, T. M. Rizzo, and J. Kopczynski. 1986. Nitrogen fixation by Azotobacter vinelandii strains having deletions in structural genes for nitrogenase. Science 232: 92–94.

34. Robinson, A. C., B. K. Burgess, and D. R. Dean. 1986. Activity, reconstitution and accumulation of nitrogenase components in Azotobacter vinelandii mutant strains containing defined deletions within the nitrogenase structural cluster. J. Bacteriol. 166: 180-186.

35. Kennedy, C., R. Gamal, R. Humphrey, J. Ramos, K. Brigle, and D. Dean. 1986. The nifH, nifM, and nifN genes of Azotobacter vinelandii: Characterization by Tn5 mutagenesis and isolation from pLAFR1 gene banks. Mol. Gen. Genet. 205: 318-325.

36. Brigle, K. E., M. C. Weiss, W. E. Newton, and D. R. Dean. 1987. Products of the iron-molybdenum cofactor-specific biosynthetic gene, nifE and nifN, are structurally homologous to the products of the nitrogenase molybdenum-iron protein genes, nifD and nifK. J. Bacteriol. 169: 1547-1553.

37. Beynon, J., A. Ally, M. Cannon, F. Cannon, M. R. Jacobson, V. Cash, and D. Dean. 1987. Comparative organization of nitrogen fixation-specific genes from Azotobacter vinelandii and Klebsiella pneumoniae: DNA sequence of the nifUSV genes. J. Bacteriol. 169: 4024-4029.

38. Robinson, A. C., D. R. Dean, and B. K. Burgess. 1987. Iron-molybdenum cofactor biosynthesis in Azotobacter vinelandii requires the iron protein of nitrogenase. J. Biol. Chem. 262: 14327-14332.

39. Brigle, K. E., R. A. Setterquist, D. R. Dean, J. S. Cantwell, M. C. Weiss, and W. E. Newton. 1987. Site-directed mutagenesis of the nitrogenase MoFe protein of Azotobacter vinelandii. Proc. Natl. Acad. Sci. USA 84: 7066-7069.

40. Bennett, L. T., M. R. Jacobson, and D. R. Dean. 1988. Isolation, sequencing, and mutagenesis of the nifF gene encoding flavodoxin from Azotobacter vinelandii. J. Biol. Chem. 263: 1364-1369.

41. Bennett, L. T., F. Cannon, and D. R. Dean. 1988. Nucleotide sequence and mutagenesis of the nifA gene from Azotobacter vinelandii. Molec. Microbiol. 2: 315-321.

42. Brigle K.E. and D. R. Dean. 1988. Revised nucleotide sequence of the Azotobacter vinelandii nifE gene. Nucleic Acids Res. 16: 5214.

43. Setterquist, R. A., K. E. Brigle, J. Benyon, M. Cannon, A. Ally, F. Cannon, and D. R. Dean. 1988. Nucleotide sequence of the nifE and nifN genes from Klebsiella pneumoniae. Nucleic Acids Res. 16: 5215.

44. Beynon, J., M. Cannon, V. Buchanan-Wollaston, A. Ally, R. Setterquist, D. Dean, and F. Cannon. 1988. The nucleotide sequence of the nifT, nifY, nifX, and nifW genes of K. pneumoniae. Nucleic Acids Res. 16: 9860.

45. Jacobson, M. R., K. E. Brigle, L. T. Bennett, R. A. Setterquist, M. S. Wilson, V. L. Cash, J. Benyon, W. E. Newton, and D. R. Dean. 1989. Physical and genetic map of the major nif gene cluster from Azotobacter vinelandii. J. Bacteriol. 171: 1017-1027.

46. Jacobson, M.R., V. L. Cash, M. C. Weiss, N. F. Laird, W. E. Newton, and D. R. Dean. 1989. Biochemical and genetic analysis of the nifUSVWZM cluster from Azotobacter vinelandii. Mol. Gen. Genet. 219: 49-57.

47. Howard, J. B., R. Davis, B. Moldenhauer, V. L. Cash, and D. R. Dean. 1989. Fe:S cluster ligands are the only cysteines required for nitrogenase Fe-protein activities. J. Biol. Chem. 264: 11270-11274.

48. Martin, A. E., B. K. Burgess, S. E. Iismaa, C. T. Smartt, M. R. Jacobson, and D. R. Dean. 1989. Construction and characterization of an Azotobacter vinelandii strain with mutations in the genes encoding flavodoxin and ferredoxin I. J. Bacteriol. 171: 3162-3167.

49. Jacobson, M. R., J. S. Cantwell, and D. R. Dean. 1990. A hybrid Azotobacter vinelandii-Clostridium pasteurianum nitrogenase iron protein that has in vivo and in vitro catalytic activity. J. Biol. Chem. 265: 19429-19433.

50. Dean, D. R., R. A. Setterquist, D. J. Scott, N. F. Laird, and W. E. Newton. 1990. Evidence that conserved residues cys-62 and cys-154 within the Azotobacter vinelandii nitrogenase MoFe protein alpha-subunit are essential for nitrogenase activity but conserved residues his-83 and cys-88 are not. Molec. Microbiol. 4: 1505-1512.

51. Scott, D. J., H. D. May, K. E. Brigle, W. E. Newton, and D. R. Dean. 1990. Role for the nitrogenase MoFe protein alpha-subunit in FeMo-cofactor binding and catalysis. Nature (London) 343: 188-190.

52. Martin, A. E., B. K. Burgess, C. D. Stout, V. L. Cash, D. R. Dean, G. M. Jensen, and P. J. Stephens. 1990. Site-directed mutagenesis of Azotobacter vinelandii ferredoxin I: [Fe-S] cluster-driven protein rearrangement. Proc. Natl. Acad. Sci. USA 87: 598-602.

53. Wang, S.-Z., D. R. Dean, J.-S. Chen, and J. L. Johnson. 1991. The N-terminal and C-terminal portions of NifV are encoded by two different genes in Clostridium pasteurianum. J. Bacteriol. 173: 3041-3046.

54. Thomann, H., M. Bernardo, W. E. Newton, and D. R. Dean. 1991. N coordination of FeMo cofactor requires his-195 of the MoFe protein alpha-subunit and is essential for biological nitrogen fixation. Proc. Natl. Acad. Sci. USA 88: 6620-6623.

55. May, H. D., D. R. Dean, and W. E. Newton. 1991. Altered nitrogenase MoFe proteins from Azotobacter vinelandii: Analysis of MoFe proteins having amino acid substitutions for the conserved cysteine residues within the beta-subunit. Biochem. J. 277: 457Ã-464.

56. Wolle, D., C.-H. Kim, D. R. Dean, and J. B. Howard. 1992. Ionic interactions in the nitrogenase complex: Properties of Fe-protein containing substitutions for arg-100. J. Biol. Chem. 267: 3667-3673.

57. Seefeldt, L. C., T. V. Morgan, D. R. Dean, and L. E. Mortenson. 1992. Mapping the site(s) of MgATP and MgADP interaction with the nitrogenase of Azotobacter vinelandii: Lysine 15 of the iron protein plays a major role in MgATP interaction. J. Biol. Chem. 267: 6680-6688.

58. Kennedy, C., and D. R. Dean. 1992. The nifU, nifS, and nifV gene products are required for activity of all three nitrogenases of Azotobacter vinelandii. Mol. Gen. Genet. 231: 494-498.

59. Scott, D. J., D. R. Dean, and W. E. Newton. 1992. Nitrogenase-catalyzed ethane production and CO-sensitive hydrogen evolution from MoFe proteins having amino acid substitutions in an alpha-subunit FeMo cofactor-binding domain. J. Biol. Chem. 267: 20002-20010.

60. Wolle, D., D. R. Dean, and J. B. Howard. 1992. Nucleotide-iron-sulfur cluster signal transduction in the nitrogenase iron-protein: The role of asp125. Science 258: 992-994.

61. Maldonado, R., A. Garzon, D. R. Dean, and J. Casadesus. 1992. Gene dosage analysis in Azotobacter vinelandii. Genetics 132: 869-878.

62. Zheng, L., R. H. White, V. L. Cash, R. F. Jack, and D. R. Dean. 1993. Cysteine desulfurase activity indicates a role for NIFS in metallocluster biosynthesis. Proc. Natl. Acad. Sci. USA 90: 2754-2758.

63. Zheng, L., R. H. White, V. L. Cash, and D. R. Dean. 1994. Mechanism for the desulfurization of L-cysteine catalyzed by the nifS gene product. Biochemistry 33: 4714-4720.

64. Dean, D. R., J. T. Bolin, and L. Zheng. 1993. Nitrogenase metalloclusters: Structures, organization, and synthesis. J. Bacteriol. 175: 6737-6744.

65. Zheng, L., and D. R. Dean. 1994. Catalytic formation of a nitrogenase iron-sulfur cluster. J. Biol. Chem. 269: 18723-18726.

66. Peters, J. W., K. Fisher, and D. R. Dean. 1994. Identification of a nitrogenase protein-protein interaction site defined by residues 59 through 67 within the Azotobacter vinelandii Fe protein. J. Biol. Chem. 269: 28076-28083.

67. Fu, W., R. F. Jack, T. V. Morgan, D. R. Dean, and M. K. Johnson. 1994. The nifU gene product from Azotobacter vinelandii is a homodimer that contains two identical [2Fe2S] clusters. Biochemistry 33: 13455-13463.

68. DeRose, V. J., C.-H. Kim, W. E. Newton, D. R. Dean, and B. M. Hoffman. 1995. Electron spin echo modulation spectroscopic analysis of altered nitrogenase MoFe proteins from Azotobacter vinelandii. Biochemistry 34: 2809-2814.

69. Peters, J. W., K. Fisher, and D. R. Dean. 1995. Nitrogenase structure and function: A biochemical-genetic perspective. Annual Review of Microbiology 49: 335-366.

70. Homer, M. J., D. R. Dean, and G. P. Roberts. 1995. Characterization of the gamma protein and its involvement in the metallocluster assembly and maturation of dinitrogenase from Azotobacter vinelandii. J. Biol. Chem. 270: 24745-24752.

71. Kim, C.-H., W. E. Newton, and D. R. Dean. 1995. The role of the MoFe protein alpha-subunit histidine-195 residue in FeMo-cofactor binding and nitrogenase catalysis. Biochemistry 34: 2798-2808.

72. Roll, J. T., V. K. Shah, D. R. Dean, and G. P. Roberts. 1995. Characteristics of NIFNE in Azotobacter vinelandii strains. J. Biol. Chem. 270: 4432-4437.

73. Peters, J. W., J. Fisher, W. E. Newton, and D. R. Dean. 1995. Involvement of the P cluster in intramolecular electron transfer within the nitrogenase MoFe protein. J. Biol. Chem. 270: 27007-27013.

74. Shen, J., D. R. Dean, and W. E. Newton. 1997. Evidence for multiple substrate-reduction and distinct inhibitor-binding sites from an altered Azotobacter vinelandii nitrogenase MoFe protein. Biochemistry 36: 4884-4894.

75. Seefeldt, L. C. and D. R. Dean. 1997. Role of nucleotides in nitrogenase catalysis. Acc. Chem. Res. 30: 260-266.

76. Zheng, L., R. H. White, and D. R. Dean. 1997. Purification of the Azotobacter vinelandii nifV-encoded homocitrate synthase. J. Bacteriol. 179: 5963-5966.

77. Magnuson, J. K., T. D. Paustian, V. K. Shah, D. R. Dean, G. P. Roberts, D. C. Rees, and J. B. Howard. 1997. Nitrogenase iron-molybdenum cofactor binding site: Protein conformational changes associated with cofactor binding. Tetrahedron 53: 11971-11984.

78. Chen, S., L. Zheng, D. R. Dean, and H. Zalkin. 1997. Role of nifS in maturation of glutamine phosphoribosylpyrophosphate amidotransferase. J. Bacteriol. 179: 7587-7590.

79. Zheng, L., V. L. Cash, D. H. Flint, and D. R. Dean. 1998. Assembly of iron-sulfur clusters. J. Biol. Chem. 273: 13264-13272.

80. Goodwin, P. J., J. N. Agar, J. T. Roll, G. P. Roberts, M. K. Johnson, and D. R. Dean. 1998. The Azotobacter vinelandii NifEN complex contains two identical [4Fe-4S] clusters. Biochemistry 37: 10420-10428.

81. Christiansen, J., P. J. Goodwin, W. N. Lanzilotta, L. C. Seefeldt, and D. R. Dean. 1998. Catalytic and biophysical properties of a nitrogenase apo-MoFe protein produced by a nifB-deletion mutant of Azotobacter vinelandii. Biochemistry 37: 12611-12623.

82. Lanzilotta, W. N., J. Christiansen, D. R. Dean, and L. C. Seefeldt. 1998. Evidence for coupled electron and proton transfer in the [8Fe-7S] cluster of nitrogenase. Biochemistry 37: 11376-11384.

83. Lee, H.-L., K. S. Thrasher, D. R. Dean, W. E. Newton, and B. M. Hoffman. 1998. 14N Electron spin-echo envelope modulation of the S=3/2 spin system of the Azotobacter vinelandii nitrogenase iron-molybdenum cofactor. Biochemistry 37: 13370-13378.

84. Chan, J. M., J. Christiansen, D. R. Dean, and L. C. Seefeldt. 1999. Spectroscopic evidence for changes in the redox state of the nitrogenase P-cluster during turnover. Biochemistry 38: 5779-5785.

85. Sorlie, M., J. Christiansen, D. R. Dean, and B. J. Hales. 1999. Detection of a new radical and FeMo-cofactor EPR signal during acetylene reduction by the alpha-H195Q mutant of nitrogenase. J. Am. Chem. Soc. 121: 9457-9458.

86. Jung, Y.-S., H. S. Gao-Sheridan, J. Christiansen, D. R. Dean, and B. K. Burgess. 1999. Purification and biophysical characterization of a new [2Fe-2S] ferredoxin from Azotobacter vinelandii, a putative [Fe-S] cluster assembly/repair protein. J. Biol. Chem. 274: 32402-32410.

87. Rangaraj, P., M. J. Ryle, W. N. Lanzilotta, P. J. Goodwin, D. R. Dean, V. K. Shah, and P. W. Ludden. 1999. Inhibition of iron-molybdenum cofactor biosynthesis by L127 NifH and evidence for a complex formation between NifH and NifNE. J. Biol. Chem. 274: 29413-29419.

88. Agar, J. N., P. Yuvaniyama, R. F. Jack, V. L. Cash, and D. R. Dean. 2000. Modular organization and identification of a mononuclear iron-binding site within the NifU protein. J. Biol. Inor. Chem. 5: 167-177.

89. Yuvaniyama, P., J. N Agar, V. L. Cash, M. K. Johnson, and D. R. Dean. 2000. NifS-directed assembly of a transient [2Fe-2S] cluster within the NifU protein. Proc. Natl. Acad. Sci. USA 97: 599-604.

90. Agar, J. N., L. Zheng, V. L. Cash, D. R. Dean, and M. K. Johnson. 2000. Role of the IscU protein in iron-sulfur cluster biosynthesis: IscS-mediated assembly of a [Fe2S2] cluster in IscU. J. Am. Chem. Soc. 122: 2136-2137.

91. Christiansen, J., J. M. Chan, L. C. Seefeldt, and D. R. Dean. 2000. The role of the MoFe protein ¡-125Phe and 125Phe residues in Azotobacter vinelandii MoFe protein-Fe protein interaction. J. Inorg. Biochem. 80: 195-204.

92. Lee, H.-I., M. Sorlie, J. Christiansen, R. Song, D. R. Dean, B. J. Hales, and B. M. Hoffman. 2000. Acetylene binding to the nitrogenase MoFe protein. J. Am. Chem. Soc. 122: 5582-5587.

93. Chan, J. M., W. Wu, D. R. Dean, and L. C. Seefeldt. 2000. Construction and characterization of a heterodimeric iron protein: Defining roles for adenosine triphosphate in nitrogenase catalysis. J. Am. Chem. Soc. 39: 7221-7228.

94. Christiansen, J., V. L. Cash, L. C. Seefeldt, and D. R. Dean. 2000. Isolation and characterization of an acetylene-resistant nitrogenase. J. Biol. Chem. 275: 11459-11464.

95. Agar, J. N., C. Krebs, J. Frazzon, B. H. Huyhn, D. R. Dean, and M. K. Johnson. 2000. IscU as a scaffold for iron-sulfur cluster biosynthesis: Sequential assembly of [2Fe-2S] and [4Fe-4S] cluster in IscU. Biochemistry 39: 7856-7862.

96. Christiansen, J., L. C. Seefeldt, and D. R. Dean. 2000. Competitive substrate and inhibitor interactions at the physiologically relevant active site of nitrogenase. J. Biol. Chem. 275: 36104-36107.

97. Benton, P. M. C., J. Christiansen, D. R. Dean, and L. C. Seefeldt. 2001. Stereospecificity of acetylene reduction catalyzed by nitrogenase. J. Am. Chem. Soc. 123: 1822-1827.

98. Benton, P. M. C., S. M. Mayer, J. Shao, B. M. Hoffman, D. R. Dean, and L. C. Seefeldt. 2001. Interaction of acetylene and cyanide with the resting state of nitrogenase alpha-96-substituted MoFe proteins. Biochemistry 40: 13816-13825.

99. Christiansen, J., D. R. Dean, and L. C. Seefeldt. 2001. Mechanistic features of the Mo-containing nitrogenase. Ann. Rev. Plant. Physiol. Plant Mol. Biol. 52: 269-295.

100. Krebs, K., J. N. Agar, A. D. Smith, J. Frazzon, D. R. Dean, B. H. Huynh, and M. K. Johnson. 2001. IscA, an alternate scaffold for Fe-S cluster biosynthesis. Biochemistry 40: 14069-14080.

101. Smith, A. D., J. N. Agar, K. A. Johnson, J. Frazzon, I. J. Amster, D. R. Dean, and M. K. Johnson. 2001. Sulfur transfer from IscS to IscU: The first step in iron-sulfur cluster biosynthesis. J. Am. Chem. Soc. 123: 11103-11104.

102. Sørlie M., J. Christiansen, B. J. Lemon, J. W. Peters, D. R. Dean, and B. J. Hales. 2001. Mechanistic features and structure of the nitrogenase -Gln-195 MoFe protein. Biochemistry 40: 1540-9.

103. Frazzon, J. and D. R. Dean. 2001. Feedback regulation of iron-sulfur cluster biosynthesis. Proc. Nat. Acad. Sci. USA 98: 14751-14753.

104. Frazzon J. and D. R. Dean. 2002. Biosynthesis of the nitrogenase iron-molybdenum-cofactor from Azotobacter vinelandii. Met. Ions Biol. Syst. 39: 163-86.

105. Mayer, S. M., W. G. Niehaus, and D. R. Dean. 2002. Reduction of short chain alkynes by a nitrogenase alpha-70Ala-substituted MoFe protein. J. Chem. Soc., Dalton Trans. pp. 80-807.

106. Schmid, B., M. W. Ribbe, O. Einsle, M. Yoshida, L. M. Thomas, D. R. Dean, D. C. Rees, and B. K. Burgess. 2002. Structure of a cofactor-deficient nitrogenase protein. Science 296: 352-356.

107. Frazzon, J., J. R. Fick, and D. R. Dean. 2002. Biosynthesis of iron-sulphur clusters is a complex and highly conserved process. Biochem. Soc. Trans. 30: 6805.

108. Lee, H. I., P. M. Benton, M. Laryukhin, R. Y. Igarashi, D. R. Dean, L. C. Seefeldt, and B. M. Hoffman. 2003. The interstitial atom of the nitrogenase FeMo-cofactor: ENDOR and ESEEM show it is not an exchangeable nitrogen. J. Am. Chem. Soc. 125: 5604-5.

109. Benton, P. M., M. Laryukhin, S. M. Mayer, B. M. Hoffman, D. R. Dean, and L. C. Seefeldt. 2003. Localization of a substrate binding site on the FeMo-cofactor in nitrogenase: trapping propargyl alcohol with an¡-70-substituted MoFe protein. Biochemistry 42: 9102œ9.

110. Ruttimann-Johnson, C., L. M. Rubio, D. R. Dean, and P. W. Ludden. 2003. VnfY is required for full activity of the vanadium-containing dinitrogenase in Azotobacter vinelandii. J. Bacteriol. 185: 2383-6.

111. Frazzon, J. and D. R. Dean. 2003. Formation of iron-sulfur clusters in bacteria: An emerging field in bioinorganic chemistry. Curr. Opin. Chem. Biol. 7: 166-73.

112. Barney, B. M., R. Y. Igarashi, P. C. Dos Santos, D. R. Dean, and L. C. Seefeldt. 2004. Substrate interaction at an iron-sulfur face of the FeMo-cofactor during nitrogenase catalysis. J. Biol. Chem. 279: 53621-4.

113. Dos Santos, P. C., A. D. Smith, J. Frazzon, V. L. Cash, M. K. Johnson, and D. R. Dean. 2004. Iron-sulfur cluster assembly: NifU-directed activation of the nitrogenase Fe protein. J. Biol. Chem. 279: 19705 œ11.

114. Lee, H. I., R. Y Igarashi, M. Laryukhin, P. E. Doan, P. C. Dos Santos, D. R. Dean, L. C. Seefeldt, and B. M. Hoffman. 2004. An organometallic intermediate during alkyne reduction by nitrogenase. J. Am. Chem. Soc. 126: 9563-9.

115. Igarashi, R. Y., P. C. Dos Santos, W. G. Niehaus, I. G. Dance, D. R. Dean, and L. C. Seefeldt. 2004. Localization of a catalytic intermediate bound to the FeMo-cofactor of nitrogenase. J. Biol. Chem. 279: 34770-5.

116. Dos Santos, P. C., D. R. Dean, Y. Hu, and M. W. Ribbe. 2004. Formation and insertion of the nitrogenase iron-molybdenum cofactor. Chem. Rev. 104:1159-1173.

117. Seefeldt, L. C., I. G. Dance, and D. R. Dean. 2004. Substrate interactions with nitrogenase: Fe versus Mo. Biochemistry 43:1401-9.

118. Johnson, D. C., P. C. Dos Santos, and D. R. Dean. 2005. NifU and NifS are required for the maturation of nitrogenase and cannot replace the function of isc-gene products in Azotobacter vinelandii. Biochem. Soc. Trans. 33: 90-3.

119. Johnson, D. C., D. R. Dean, A. D. Smith, and M. K. Johnson. 2005. Structure, function, and formation of biological iron-sulfur clusters. Annu. Rev. Biochem. 4:247-81.

120. Barney, B. M., M. Laryukhin, R. Y. Igarashi, H.-I. Lee, P. C. Dos Santos, T.-C. Yang, B. M. Hoffman, D. R. Dean, and L. C. Seefeldt. 2005. Trapping a hydrazine reduction intermediate on the nitrogenase active site. Biochemistry 44:8030-7.

121. Igarashi, R. Y., M. Laryukhin, P. C. Dos Santos, H.-I. Lee, D. R. Dean, L. C. Seefeldt, and B. M. Hoffman. 2005. Trapping H- bound to the nitrogenase FeMo-cofactor active site during H2 evolution: characterization by ENDOR spectroscopy. J. Am. Chem. Soc. 127: 6231-41.

122. Dos Santos, P. C., R. Y. Igarashi, H.-I. Lee, B. M. Hoffman, L. C. Seefeldt, and D. R. Dean. 2005. Substrate interactions with the nitrogenase active site. Acc. Chem. Res. 38: 208-14.

123. Smith, A. D., G. N. Jameson, P. C. Dos Santos, J. N. Agar, S. Naik, C. Krebs, J. Frazzon, D. R. Dean, B. H. Huynh, and M. K. Johnson. 2005. NifS-mediated assembly of [4Fe-4S] clusters in the N-terminal and C-terminal domains of the NifU scaffold protein. Biochemistry 44: 12955-69.

124. Yang, T.-C., N. K. Maeser, M. Laryukhin, H.-I. Lee, D. R. Dean, L. C. Seefeldt, and B. M. Hoffman. 2005. The interstitial atom of the nitrogenase FeMo-cofactor: ENDOR and ESEEM evidence that it is not a nitrogen. J. Am. Chem. Soc. 127:12804-05.

125. Lee, H.-I., M. Sørlie, J. Christiansen, T.-C. Yang, J. Shao, D. R. Dean, B. J. Hales, and B. H. Hoffman. 2005. Structure, electron inventory, kinetic assignment, and bonding of nitrogenase turnover intermediates with C2H2 and CO: An 57Fe and 1H ENDOR study. J. Am. Chem. Soc. 127: 15880-90.

126. Barney, B. M., T.-C. Yang, R. Y. Igarashi, P. C. Dos Santos, M. Laryukhin, H.-I. Lee, B. M. Hoffman, D. R. Dean, and L. C. Seefeldt. 2005. Intermediates trapped during nitrogenase reduction of N2, CH3N2H, and N2H4. J. Am. Chem. Soc. 127: 14960-61.

127. Smith, A. D., J. Frazzon, D. R. Dean, and M. K. Johnson, 2005. Role of conserved cysteines in mediating sulfur transfer from IscS to IscU. FEBS Lett. 579: 5236-40.

128. Barney, B. M., H.-I. Lee, P. C. Dos Santos, D. R. Dean, and L. C. Seefeldt. 2006. Breaking the N2 triple bond: insights into the nitrogenase mechanism. Dalton Trans. 19: 2277-2284.

129. Johnson, D. C., M. C. Unciuleac, and D. R. Dean. 2006. Controlled expression and functional analysis of iron-sulfur cluster biosynthetic components within Azotobacter vinelandii. J. Bact. 188: 7551-7561.

130. Barney, B. M., J. McLead, D. Lukoyanov, M. Laryukhin, T.-C. Yang, B. M. Hoffman, D. R. Dean, and L. C. Seefeldt. 2006. Diazene is a substrate for nitrogenase: Insights into the N2 reduction reaction pathway. Biochemistry 46: 6784-6794.

131. Hernandez, J. A., R. Y. Igarashi, B. Soboh, L. Curatti, D. R. Dean, P. W. Ludden, and L. M. Rubio. 2007. NifX and NifEN exchange NifB-co and the VK-cluster, a newly discovered intermediate of the iron- molybdenum cofactor biosynthetic pathway. Mol. Microbiol. 63: 177-192.

132. Barney, B. M., D. Lukoyanov, T.-C. Yang, D. R. Dean, B. M. Hoffman, and L. C. Seefeldt, 2006. A Methyldiazene (HN=N-CH3)-derived species bound to the nitrogenase active site FeMo-cofactor: implications for mechanism. Proc. Nat. Acad. Sci. 103: 17113-17118.

133. Frazzon, A. P.-G., M. V. Ramirez, U. Warek, J. Frazzon, D. R. Dean, and B. S. Winkel. 2006. Functional analysis of Arabidopsis thaliana genes involved in mitochondrial iron-sulfur cluster assembly. Plant Molecular Biology 64: 225-240.

134. Lukoyanov, D., B. Barney, D. R. Dean, L. C. Seefeldt, and B. M. Hoffman. 2007. Connecting nitrogenase intermediates with the N2 reduction kinetic scheme by a relaxation protocol and identifying the N2 binding state. Proc, Nat. Acad Sci. 104: 1451-1455.

135. Dos Santos, P. C., D. C. Johnson, B. E. Ragle, M. C. Unciuleac and D. R. Dean. 2007. Controlled expression of nif and isc iron-sulfur protein maturation components reveals target specificity and limited functional replacement between the two systems. J. Bacteriol. 189:2854-2862.

136. Unciuleac, M.-C., K. Chandramouli, S. Naik, S. Mayer, B.-H. Huynh, B.-H., M. K. Johnson and D. R. Dean, (2007) In vitro activation of apo-aconitase using a [4Fe-4S] cluster-loaded form of the IscU [Fe-S] cluster scaffolding protein. Biochemistry 46: 6812-6821.

137. Chandramouli, K., M.-C. Unciuleac, S. Naik, D.R. Dean, B.-H. Huynh, and M. K. Johnson (2007) Formation and properties of [4Fe-4S] clusters on the IscU scaffold protein. Biochemistry 46: 6804-6811.

138. Dos Santos, P. C., S. M. Noakes, B. M. Barney, L. C. Seefeldt, and D. R. Dean (2007) Alkyne substrate interaction within the nitrogenase MoFe protein. J. Inorg, Biochem.101: 1642-1648.

139. Lukoyanov, D., V. Pelmenschikov, N. Maeser, M. Laryukhin, T. C. Yang, L. Noodleman, D. R. Dean, D. A. Case, L. C. Seefeldt and Hoffman, B. H. (2007) Testing if the interstitial aton, X, of the nitrogenase molybdenum-iron cofactor is N or C: ENDOR, ESEEM and DFT studies of the S=3/2 resting state in multiple environments. Inorganic Chemistry, in press

140. Raulfs, E. C., I. P. O'Carroll, P. C. Dos Santos, M.-C. Unciuleac and D. R. Dean In vivo iron-sulfur cluster formation (2008) Proceedings of the National Academy of Science (USA) 105: 8591-8596.

141. Bandyopadhy, S., S. G. Naik, I. P. O'Carroll, B.-H. Huynh, D. R. Dean, M. K. Johnson and P. C. Dos Santos. A proposed role for the Azotobacter vinelandii NfuA protein as an intermediate iron-sulfur cluster carrier (2008) Biol. Chem. 283: 14092-14099.

142. Seefeldt, L. C., B. M. Hoffman and D. R. Dean. Nitrogenase Mechanism (2009) Lance Seefeldt, Brian Hoffman, and Dennis R. Dean. Annual Reviews of Biochemistry 78: 701-722

143. Dos Santos, P. C. and D. R. Dean A newly discovered role for iron-sulfur clusters. (2008) Proceedings of the National Academy of Sciences (USA) 105: 11589-11590.

144. Hoffman, B. M., D. R. Dean and L. C. Seefeldt (2009) Climbing Nitrogenase: Towards the mechanism of N2 reduction. (2008) Accounts of Chemical Research, 19:609-619.

145. Barney B. M., D. Lukoyanov, R. Y.Igarashi, M. Laryukhin, T.C Yang, D. R. Dean, B. M. Hoffman, L. C. Seefeldt. Biochemistry (2009) Trapping an intermediate of dinitrogen (N2) reduction on nitrogenase. 38: 9094-90002.

146. Barney B. M., M. G. Yurth, P. C. Dos Santos, D. R. Dean and L. C. Seefeldt. (2009) A substrate channel in the nitrogenase MoFe protein. J Biol Inorg Chem. 7:1015-1022.

147. Setubal J. C., P. C. dos Santos, B. S. Goldman, H, G. Espin, L. M Rubio, S. Valla, N. F. Almeida, D. Balasubramanian, L. Cromes, L. Curatti, Z. Du, E. Godsy, B. Goodner, K. Hellner-Burris, J. A. Hernandez, K. Houmiel, J. Imperial, C. Kennedy, T. J. Larson, P. Latreille, L. S. Ligon, J. Lu, M. Maerk, N. M. Miller, S. Norton , I. P. O'Carroll, I. Paulsen, E. C, Raulfs, R. Roemer, J. Rosser, D. Segura, S. Slater, S. L. Stricklin , D. J. Studholme, J. Sun, C. J. Viana, E. Wallin, B. Wang, C. Wheeler, H. Zhu, D. R. Dean, R. Dixon R and D Wood. (2009) Genome sequence of Azotobacter vinelandii, an obligate aerobe specialized to support diverse anaerobic metabolic processes. J Bacteriol. 191:4534-45.

148. Lukoyanov, D., Z. Y. Yang, D. R. Dean, L. C. Seefeldt and B. M. Hoffman (2010) Is Mo involved in hydride binding of the four-electron reduced (E4) intermediate of the nitrogenase MoFe protein? J. Am. Chem. Soc. 132: 2526-2528.

149. Sarma, R. B. M. Barney, S. Keable, D. R. Dean and J. W. Peters (2010) Insights into substrate binding at FeMo-cofactor in nitrogenase from the structure of an alpha 70 Ile MoFe protein. J. Inorg. Biochem. 104: 385-389.

150. Danyal K., Mayweather D., Dean DR., Seefeldt LC and Hoffman BM. (2010) Conformational gating of electron transfer from the nitrogenase Fe protein to MoFe protein. J. Am. Chem. Soc. 6894-95.

151. Danyal K. Inglet BS, Vincent KA, Barney BM, Hoffman BM, Armstrong FA, Dean DR, Seefeldt LC. (2010) Uncoupling nitrogenase: catalytic reduction of hydrazine to annomnia by a MoFe protein in the absence of Fe protein-ATP. J Am Chem Soc. 132: 13197-9.

152. Dos Santos PC, Dean DR. (2010) Bioinorganic chemistry: electrons in Fe-S protein assembly. Nat Chem Biol. 6: 700-1.

153. Yang ZY, Seefeldt LC, Dean DR, Cramer SP, George SJ. (2011) Steric control of the Hi-CO MoFe nitrogenase complex revealed by stopped-flow infrared spectroscopy. Angew Chem Int Ed Engl. 50: 272-5.

154. Dos Santos PC, Dean DR. (2011) Co-ordination and fine-tuning of nitrogen fixation in Azotobacter vinelandii. Mol Microbiol. 79: 1132-5.

155. Yang ZY, Dean DR, Seefeldt LC. (2011) Molybdenum nitrogenase catalyzes the reduction and coupling of CO to form hydrocarbons. J Biol Chem. 286: 19417-21.

156. Hamilton TL, Ludwig M, Dixon R, Boyd ES, Dos Santos PC, Setubal JC, Bryant DA, Dean DR, Peters JW. (2011) Transcriptional profiling of nitrogen fixation in Azotobacter vinelandii. J Bacteriol. 193: 4477-86.

157. Hamilton TL, Jacobson M, Ludwig M, Boyd ES, Bryant DA, Dean DR, Peters JW. (2011) Differential accumulation of nif structural gene mRNA in Aztobacter vinelandii. J Bacteriol. 193:4534-6.

158. Lukoyanov D, Dikanov SA, Yang ZY, Barney BM, Samoilova RI, Narasimhulu KV, Dean DR, Seefeldt LC, Hoffman BM. ENDOR/HYSCORE studies of the common intermediate trapped during nitrogenase reduction of N2H2, CH3N2H, and N2H4 support an alternating reaction pathway for N2 reduction. J Am Chem Soc. 133:11655-64.

159. Danyal K, Dean DR, Hoffman BM, Seefeldt LC. (2011) Electron transfer within nitrogenase: evidence for a deficit-spending mechanism. Biochemistry. 50: 9255-63.

160. Doan PE, Tesler J, Barney BM, Igarashi RY, Dean DR, Seefeldt LC, Hoffman BM. (2011) 57Fe ENDOR spectroscopy and 'electron inventory' analysis of the nitrogenase E4 intermediate suggest the metal-ion core of FeMo-cofactor cycles through only one redox couple. J Am Chem Soc. 133: 17329-40.

161. Liu Y, Dos Santos PC, Zhu X, Orlando R, Dean DR, Soll D, Yuan J. (2011) The catalytic mechanism of Sep-tRNA:Cys-tRNA synthase: sulfur transfer is mediated by disulfide and persulfide. J Bio Chem. 287:5426-5433.