Work in my lab is concerned with the biosynthesis, structure, function, and genetics of the coenzymes. At present, our work is focused on the coenzymes in the hyperthermophilic methanoarchaea Methanococcus jannaschii, a member of recently defined third kingdom of organisms on our planet. We are trying to develop an unified theory to understand how the biosynthesis of the coenzymes and thus metabolism, has evolved on our planet by studying the evolution of their biosynthetic enzymes in this organism as compared with other organisms.

The work involves all aspects of both classical and modern biochemistry and range from synthetic organic chemistry, development of biosynthetic pathways, enzymology, bioorganic chemistry, enzyme isolation and purification and identification, molecular biology, and genetics. The work also involves the development of methods for the isolation and analysis of these unique coenzymes and their precursors on the micro scale using gas chromatograph-mass spectrometry.

Kezmarsky, N. D., Xu, H., Graham, D. E., and White, R. H. (2005) Identification and characterization of a L-tyrosine decarboxylase in Methanocaldococcus jannaschii. BBA, 1722:175-182.   [Abstract]

Ownby, K., Xu, H., and White, R. H. (2005) A Methanocaldococcus jannaschii archaeal signature gene encodes for a 5-formaninoimidazole-4-carboxamide-1-beta-d-ribofuranosyl 5'-monophosphate synthetase. J. Biol. Chem. 280(12):10881-10887.   [Abstract]

White, R. H. (2004) L-aspartate semialdehyde and a 6-deoxy-5-ketohexose 1-phosphate are the precursors to the aromatic amino acids in Methanocaldococcus jannachii. Biochem. 43:7618-7627.   [Abstract]

Tolbert, W. D., Graham, D. E., White, R. H., and Ealick, S. E. (2003) Pyruvoyl-Dependent Arginine Decarboxylase from Methanococcus jannaschii: Crystal Structures of the Self-Cleaved and S53A Proenzyme Forms. Structure 11:285-294.   [Abstract]

Wise, E. L., Graham, D. E., White, R. H., and Rayment, I. (2003) The structural determination of phosphosulfolactate synthase from Methanococcus jannaschii at 1.7-A resolution. J. Biol. Chem. 278:45858-45863.   [Abstract]

Huffman, J. L., Hong, L., White, R. H., and Tainer, A. (2003) Structural Basis for Recognition and Catalysis by the Bifunctional dCTP Deaminase and dUTPase from the Hyperthermophilic Archaeon Methanococcus jannaschii. J. Molecular Bio., 331:885-896.   [Abstract]

Graupner, M. and White, R. H. (2003) The Methanococcus jannaschii Coenzyme F420 Analogs Contain a Terminal alpha-Linked Glutamate. J. Bact. 185:4662-4665.   [Abstract]

Graham, D. E., Xu, H., and White, R. H. (2003) Identification of the 7,8-didemethyl-8-hydroxy-5-deazariboflavin synthase required for coenzyme F420 biosynthesis. Arch. Microbiol. 180:455-464.   [Abstract]

Graham, D. E., Harich, K. C., and White, R. H. (2003) Reductive dehalogenation of monobromobimane by tris(2-carboxyethyl)phosphine. Anal. Biochem. 318:325-328.   [Abstract]

Li, H., Graupner, M., Xu, H., and White, R. H. (2003) CofE catalyzes the addition of two glutamates to F420-0 in F420 coenzyme biosynthesis in Methanococcus jannaschii. Biochem. 42:9771-9778.   [Abstract]