Research Interests   Microbial Biochemistry; Redox Proteins; N-Oxidation; Microbial Detoxification

We focus on the structure and catalytic mechanism of the metallo-enzymes which oxidize ammonia to nitrite in the chemolithoautrophic bacterium, Nitrosomonas. To illustrate, we have found that the remarkable hydroxylamine-oxidizing enzyme contains 8 covalent bond c-hemes, one of which is also covalently crosslinked to a tyrosine. In a new family of beta-sheet c-cytochrmomes a N-oxide dehydrogenase, cytochrome P460, has a lys-heme covalent crosslink. we studty structure by protein chemistry and optical spectroscopy. Collaborators employ magnetic spectroscopy. We sequence genes to help answer regulatory and evolutionary questions and to facilitate determination of x-ray structures by collaborators.

Hooper, A.B., Arciero, D.M., Bergmann, D., and Hendrich, M.P. (2005) The Oxidation of Ammonia as an Energy Source in Bacteria. in Respiration in Davide Zannoni, Ed. Respiration in Archaea and Bacteria: Diversity of Procaryotic Respiratory Systems pp 121-147. Vol 16 of Advances in Photosynthesis and Respiration, Govindjee, Ed. Springer, Dordrecht, the Netherlands.

Chain, P , Lamerdin, J., Larimer, F., Regala, W , Lao, V. Land , M, Hauser, L, Hooper A., Klotz, M., Norton J., Sayavedra-Soto L., Arciero D., Hommes N., Whittaker, M., Arp, D. (2003) Complete genome sequence of the ammonia oxidizing bacterium and obligate chemolithoautotroph Nitrosomonas europaea. J. Bacteriol. 185, 2759-2773.

Hendrich, M.P., Upadhyay, A.K., Riga, J. Arciero, D.M. and Hooper, A.B. (2002) Spectroscopic Characterization of the NO adduct of Hydroxylamine Oxidoreductase. Biochemistry 41(14); 4603-461.

Bergmann, D.B., Hooper, A.B. and Klotz, M., (2005) Structure and Sequence Conservation of hao Cluster Genes of Autotrophic Ammonia-Oxidizing Bacteria: Evidence for their Evolutionary History. Appl. Envt. Microbiol. 71: 5371-5382.

Arciero, D.M., Pierce, B. S., Hendrich, M. P., and Hooper, A.B. (2002) Nitrosocyanin, a Red Cupredoxin-like Protein from Nitrosomonas europaea. Biochemistry, 41,1703-1709.

Lieberman, R. L. , Arciero, D.M., Hooper, A.B. and Rosensweig, A.C. (2001) Crystal structure of a novel red copper protein from Nitrosomonas europaea. Biochemistry, 40 (19): 5674-5681.

Iverson, T., Arciero, D.M., Hooper,A.B. and Rees, D.C. (2001) High-resolution structures of cytochrome c554 from Nitrosomonas europaea. J. Biological Inorganic Chem, 6: 390-397.

Upadhyay, A.K., Petasis, D.T. Arciero, D.M. Hooper, A.B. and Hendrich , M.P. (2003) Spectroscopic Characterization and Assignment of Reduction Potentials in the Tetraheme Cytochrome c554 from Nitrosomonas europaea. J. Am. Chem. Soc. 125, 1738-1747.

Bergmann, D.J. and Hooper, A.B. (2003) Cytochrome P460 of Nitrosomonas europaea : Formation of the Heme-Lysine Cross-link in a Heterologous Host and Mutagenic Conversion to a Non-Cross-linked Cytochrome c. Eur. J. Biochem 270, 1935-1941.