@article {529,
	title = {Definitive evidence for monoanionic binding of 2,3-dihydroxybiphenyl to 2,3-dihydroxybiphenyl 1,2-dioxygenase from UV resonance Raman spectroscopy, UV/Vis absorption spectroscopy, and crystallography},
	journal = {Journal of the American Chemical Society},
	volume = {124},
	number = {11},
	year = {2002},
	note = {ISI Document Delivery No.: 531UMTimes Cited: 53Cited Reference Count: 79},
	month = {Mar},
	pages = {2485-2496},
	type = {Article},
	abstract = {Ultraviolet resonance Raman spectroscopy (UVRRS), electronic absorption spectroscopy, and X-ray crystallography were used to probe the nature of the binding of 2,3-dihydroxybiphenyl (DHB) to the extradiol ring-cleavage enzyme, 2,3-dihydroxybiphenyl 1,2-dioxygenase (DHBD; EC 1.13.11.39). The lowest lying transitions in the electronic absorption spectrum of DHBD-bound DHB occurred at 299 nm, compared to 305 nm for the monoanionic DHB species in buffer. In contrast, the corresponding transitions in neutral and dianionic DHB occurred at 283 and 348 nm, respectively, indicating that DHBD-bound DHB is monoanionic. These binding-induced spectral changes, and the use of custom-designed optical fiber probes, facilitated UVRR experiments. The strongest feature of the UVRR spectrum of DHB was a Y8a-like mode around 1600 cm(-1), whose position depended strongly on the protonation state of the DHB. In the spectrum of the DHBD-bound species, this feature occurred at 1603 cm-1, as observed in the spectrum of monoanionic DHB. Raman band shifts were observed in deuterated solvent, ruling out dianionic binding of the substrate. Thus, the electronic absorption and UVRRS data demonstrate that DHBD binds its catecholic substrate as a monoanion, definitively establishing this feature of the proposed mechanism of extradiol dioxygenases. This conclusion is supported by a crystal structure of the DHBD:DHB complex at 2.0 Angstrom resolution, which suggests that the substrate{\textquoteright}s 2-hydroxyl substituent, and not the 3-hydroxyl group, deprotonates upon binding. The structural data also show that the aromatic rings of the enzyme-bound DHB are essentially orthogonal to each other. Thus, the 6 nm blue shift of the transition for bound DHB relative to the monoanion in solution could indicate a conformational change upon binding. Catalytic roles of active site residues are proposed based on the structural data and previously proposed mechanistic schemes.},
	keywords = {3, 4-DIOXYGENASE, BIPHENYL, CRYSTAL-STRUCTURE, EXTRADIOL CATECHOL DIOXYGENASES, FE(II) ACTIVE-SITE, FE3+ LIGAND, LIGAND-BINDING, MECHANISM, MOLECULAR-STRUCTURE, PROTOCATECHUATE, SUBSTRATE-BINDING},
	isbn = {0002-7863},
	url = {<Go to ISI>://000174435700037},
	author = {Vaillancourt, F. H. and Barbosa, C. J. and Spiro, T. G. and Bolin, J. T. and Blades, M. W. and Turner, R. F. B. and Eltis, L. D.}
}
@article {529,
	title = {Definitive evidence for monoanionic binding of 2,3-dihydroxybiphenyl to 2,3-dihydroxybiphenyl 1,2-dioxygenase from UV resonance Raman spectroscopy, UV/Vis absorption spectroscopy, and crystallography},
	journal = {Journal of the American Chemical Society},
	volume = {124},
	number = {11},
	year = {2002},
	note = {ISI Document Delivery No.: 531UMTimes Cited: 53Cited Reference Count: 79},
	month = {Mar},
	pages = {2485-2496},
	type = {Article},
	abstract = {Ultraviolet resonance Raman spectroscopy (UVRRS), electronic absorption spectroscopy, and X-ray crystallography were used to probe the nature of the binding of 2,3-dihydroxybiphenyl (DHB) to the extradiol ring-cleavage enzyme, 2,3-dihydroxybiphenyl 1,2-dioxygenase (DHBD; EC 1.13.11.39). The lowest lying transitions in the electronic absorption spectrum of DHBD-bound DHB occurred at 299 nm, compared to 305 nm for the monoanionic DHB species in buffer. In contrast, the corresponding transitions in neutral and dianionic DHB occurred at 283 and 348 nm, respectively, indicating that DHBD-bound DHB is monoanionic. These binding-induced spectral changes, and the use of custom-designed optical fiber probes, facilitated UVRR experiments. The strongest feature of the UVRR spectrum of DHB was a Y8a-like mode around 1600 cm(-1), whose position depended strongly on the protonation state of the DHB. In the spectrum of the DHBD-bound species, this feature occurred at 1603 cm-1, as observed in the spectrum of monoanionic DHB. Raman band shifts were observed in deuterated solvent, ruling out dianionic binding of the substrate. Thus, the electronic absorption and UVRRS data demonstrate that DHBD binds its catecholic substrate as a monoanion, definitively establishing this feature of the proposed mechanism of extradiol dioxygenases. This conclusion is supported by a crystal structure of the DHBD:DHB complex at 2.0 Angstrom resolution, which suggests that the substrate{\textquoteright}s 2-hydroxyl substituent, and not the 3-hydroxyl group, deprotonates upon binding. The structural data also show that the aromatic rings of the enzyme-bound DHB are essentially orthogonal to each other. Thus, the 6 nm blue shift of the transition for bound DHB relative to the monoanion in solution could indicate a conformational change upon binding. Catalytic roles of active site residues are proposed based on the structural data and previously proposed mechanistic schemes.},
	keywords = {3, 4-DIOXYGENASE, BIPHENYL, CRYSTAL-STRUCTURE, EXTRADIOL CATECHOL DIOXYGENASES, FE(II) ACTIVE-SITE, FE3+ LIGAND, LIGAND-BINDING, MECHANISM, MOLECULAR-STRUCTURE, PROTOCATECHUATE, SUBSTRATE-BINDING},
	isbn = {0002-7863},
	url = {<Go to ISI>://000174435700037},
	author = {Vaillancourt, F. H. and Barbosa, C. J. and Spiro, T. G. and Bolin, J. T. and Blades, M. W. and Turner, R. F. B. and Eltis, L. D.}
}
@article {4751,
	title = {The first structure of UDP-glucose dehydrogenase reveals the catalytic residues necessary for the two-fold oxidation},
	journal = {Biochemistry},
	volume = {39},
	number = {23},
	year = {2000},
	note = {ISI Document Delivery No.: 324PRTimes Cited: 62Cited Reference Count: 49},
	month = {Jun},
	pages = {7012-7023},
	type = {Article},
	abstract = {Bacterial UDP-glucose dehydrogenase (UDPGlcDH) is essential for formation of the antiphagocytic capsule that protects many virulent bacteria such as Streptococcus pyrogenes and Streptococcus pneumoniae type 3 from the host{\textquoteright}s immune system. We have determined the X-ray structures of both native and Cys260Ser UDPGlcDH from S. pyogenes (74\% similarity to S. pneumoniae) in ternary complexes with UDP-xylose/NAD(+) and UDP-glucuronic acid/NAD(H), respectively. The 402 residue homodimeric UDPGlcDH is composed of an N-terminal NAD(+) dinucleotide binding domain and a C-terminal UDP-sugar binding domain connected by a long (48 Angstrom) central alpha-helix. The first 290 residues of UDPGlcDH share structural homology with 6-phosphogluconate dehydrogenase, including conservation of an active site lysine and asparagine that are implicated in the enzyme mechanism. Also proposed to participate in the catalytic mechanism are a threonine and a glutamate that hydrogen bond to a conserved active site water molecule suitably positioned for general acid/base catalysis.},
	keywords = {alanine, ALIGNMENT, CRYSTAL-STRUCTURE, ESCHERICHIA-COLI, GROUP-A STREPTOCOCCI, INSIGHTS, MECHANISM, MOLECULAR CHARACTERIZATION, REDUCTASE, SUBSTRATE-BINDING},
	isbn = {0006-2960},
	url = {<Go to ISI>://000087631000031},
	author = {Campbell, R. E. and Mosimann, S. C. and van de Rijn, I. and Tanner, M. E. and Strynadka, N. C. J.}
}
