@article {1204,
	title = {Horse Liver Alcohol Dehydrogenase: Zinc Coordination and Catalysis.},
	journal = {Biochemistry},
	volume = {56},
	year = {2017},
	month = {2017 07 18},
	pages = {3632-3646},
	abstract = {<p>During catalysis by liver alcohol dehydrogenase (ADH), a water bound to the catalytic zinc is replaced by the oxygen of the substrates. The mechanism might involve a pentacoordinated zinc or a double-displacement reaction with participation by a nearby glutamate residue, as suggested by studies of human ADH3, yeast ADH1, and some other tetrameric ADHs. Zinc coordination and participation of water in the enzyme mechanism were investigated by X-ray crystallography. The apoenzyme and its complex with adenosine 5{\textquoteright}-diphosphoribose have an open protein conformation with the catalytic zinc in one position, tetracoordinated by Cys-46, His-67, Cys-174, and a water molecule. The bidentate chelators 2,2{\textquoteright}-bipyridine and 1,10-phenanthroline displace the water and form a pentacoordinated zinc. The enzyme-NADH complex has a closed conformation similar to that of ternary complexes with coenzyme and substrate analogues; the coordination of the catalytic zinc is similar to that found in the apoenzyme, except that a minor, alternative position for the catalytic zinc is \~{}1.3 {\r A} from the major position and closer to Glu-68, which could form the alternative coordination to the catalytic zinc. Complexes with NADH and N-1-methylhexylformamide or N-benzylformamide (or with NAD and fluoro alcohols) have the classical tetracoordinated zinc, and no water is bound to the zinc or the nicotinamide rings. The major forms of the enzyme in the mechanism have a tetracoordinated zinc, where the carboxylate group of Glu-68 could participate in the exchange of water and substrates on the zinc. Hydride transfer in the Michaelis complexes does not involve a nearby water.</p>
},
	keywords = {2,2{\textquoteright}-Dipyridyl, Adenosine Diphosphate Ribose, Alcohol Dehydrogenase, Animals, Catalytic Domain, Crystallography, X-Ray, Formamides, Horses, Kinetics, Liver, Models, Molecular, NAD, Phenanthrolines, Protein Binding, Protein Conformation, Water, Zinc},
	issn = {1520-4995},
	doi = {10.1021/acs.biochem.7b00446},
	author = {Plapp, Bryce V and Savarimuthu, Baskar Raj and Ferraro, Daniel J and Rubach, Jon K and Brown, Eric N and Ramaswamy, S}
}
@article {1167,
	title = {Blue protein with red fluorescence.},
	journal = {Proc Natl Acad Sci U S A},
	volume = {113},
	year = {2016},
	month = {2016 10 11},
	pages = {11513-11518},
	abstract = {<p>The walleye (Sander vitreus) is a golden yellow fish that inhabits the Northern American lakes. The recent sightings of the blue walleye and the correlation of its sighting to possible increased UV radiation have been proposed earlier. The underlying molecular basis of its adaptation to increased UV radiation is the presence of a protein (Sandercyanin)-ligand complex in the mucus of walleyes. Degradation of heme by UV radiation results in the formation of Biliverdin IXα (BLA), the chromophore bound to Sandercyanin. We show that Sandercyanin is a monomeric protein that forms stable homotetramers on addition of BLA to the protein. A structure of the Sandercyanin-BLA complex, purified from the fish mucus, reveals a glycosylated protein with a lipocalin fold. This protein-ligand complex absorbs light in the UV region (λ of 375 nm) and upon excitation at this wavelength emits in the red region (λ of 675 nm). Unlike all other known biliverdin-bound fluorescent proteins, the chromophore is noncovalently bound to the protein. We provide here a molecular rationale for the observed spectral properties of Sandercyanin.</p>
},
	keywords = {Biliverdine, Crystallography, X-Ray, Fluorescence, Models, Molecular, Proteins, Recombinant Proteins},
	issn = {1091-6490},
	doi = {10.1073/pnas.1525622113},
	author = {Ghosh, Swagatha and Yu, Chi-Li and Ferraro, Daniel J and Sudha, Sai and Pal, Samir Kumar and Schaefer, Wayne F and Gibson, David T and Ramaswamy, S}
}
