@article {976,
	title = {Structural characterization of the RNase E S1 domain and identification of its oligonucleotide-binding and dimerization interfaces},
	journal = {Journal of Molecular Biology},
	volume = {341},
	number = {1},
	year = {2004},
	note = {ISI Document Delivery No.: 841JCTimes Cited: 25Cited Reference Count: 65},
	month = {Jul},
	pages = {37-54},
	type = {Article},
	abstract = {S1 domains occur in four of the major enzymes of mRNA decay in Escherichia coli: RNase E, PNPase, RNase II, and RNase G. Here, we report the structure of the S1 domain of RNase E, determined by both X-ray crystallography and NMR spectroscopy. The RNase E S1 domain adopts an OB-fold, very similar to that found with PNPase and the major cold shock proteins, in which flexible loops are appended to a well-ordered five-stranded beta-barrel core. Within the crystal lattice, the protein forms a dimer stabilized primarily by intermolecular hydrophobic packing. Consistent with this observation, light-scattering, chemical crosslinking, and NMR spectroscopic measurements confirm that the isolated RNase E S1 domain undergoes a specific monomer-dimer equilibrium in solution with a K-D value in the millimolar range. The substitution of glycine 66 with serine dramatically destabilizes the folded structure of this domain, thereby providing an explanation for the temperature-sensitive phenotype associated with this mutation in full-length RNase E. Based on amide chemical shift perturbation mapping, the binding surface for a single-stranded DNA dodecamer (K-D = 160(+/-40) muM) was identified as a groove of positive electrostatic potential containing several exposed aromatic side-chains. This surface, which corresponds to the conserved ligand-binding cleft found in numerous OB-fold proteins, lies distal to the dimerization interface, such that two independent oligonucleotide-binding sites can exist in the dimeric form of the RNase E S1 domain. Based on these data, we propose that the S1 domain serves a dual role of dimerization to aid in the formation of the tetrameric quaternary structure of RNase E as described by Callaghan et al. in 2003 and of substrate binding to facilitate RNA hydrolysis by the adjacent catalytic domains within this multimeric enzyme. (C) 2004 Elsevier Ltd. All rights reserved.},
	keywords = {BACILLUS-SUBTILIS, C-13-LABELED PROTEINS, CELLULOMONAS-FIMI, CENC, CHEMICAL-SHIFT, COLD-SHOCK PROTEIN, ESCHERICHIA-COLI, MACROMOLECULAR STRUCTURES, MESSENGER-RNA, OB-fold, protein structure, RNA binding, RNase E, ROTATIONAL DIFFUSION, S1 domain, SELECTIVE H-1-N-15 CORRELATIONS},
	isbn = {0022-2836},
	url = {<Go to ISI>://000222925100005},
	author = {Schubert, M. and Edge, R. E. and Lario, P. and Cook, M. A. and Strynadka, N. C. J. and Mackie, G. A. and McIntosh, L. P.}
}
@article {4667,
	title = {Sugar ring distortion in the glycosyl-enzyme intermediate of a family G/11 xylanase},
	journal = {Biochemistry},
	volume = {38},
	number = {17},
	year = {1999},
	note = {ISI Document Delivery No.: 193YMTimes Cited: 122Cited Reference Count: 50},
	month = {Apr},
	pages = {5346-5354},
	type = {Article},
	abstract = {The 1.8 Angstrom resolution structure of the glycosyl-enzyme intermediate formed on the retaining beta-1,4-xylanase from Bacillus circulans has been determined using X-ray crystallographic techniques. The 2-fluoro-xylose residue bound in the -1 subsite adopts a B-2,B-5 (boat) conformation, allowing atoms C5, O5, C1, and C2 of the sugar to achieve coplanarity as required at the oxocarbenium ion-like transition states of the double-displacement catalytic mechanism. Comparison of this structure to that of a mutant of this same enzyme noncovalently complexed with xylotetraose [Wakarchuk et al. (1994) Protein Sci. 3, 467-475] reveals a number of differences beyond the distortion of the sugar moiety. Most notably, a bifurcated hydrogen bond interaction is formed in the glycosyl-enzyme intermediate involving H-eta of Tyr69, the endocyclic oxygen (O5) of the xylose residue in the -1 subsite, and O-epsilon 2 of the catalytic nucleophile, Glu78. To gain additional understanding of the role of Tyr69 at the active site of this enzyme, we also determined the 1.5 Angstrom resolution structure of the catalytically inactive Tyr69Phe mutant. Interestingly, no significant structural perturbation due to the loss of the phenolic group is observed. These results suggest that the interactions involving the phenolic group of Tyr69, O5 of the proximal saccharide, and Glu78 O-epsilon 2 important for the catalytic mechanism of this enzyme, and it is proposed that, through charge redistribution, these interactions serve to stabilize the oxocarbenium-like ion of the transition state. Studies of the covalent glycosyl-enzyme intermediate of this xylanase also provide insight into specificity, as contacts with C5 of the xylose moiety exclude sugars with hydroxymethyl substituents, and the mechanism of catalysis, including aspects of stereoelectronic theory as applied to glycoside hydrolysis.},
	keywords = {ACTIVE-SITE RESIDUES, BACILLUS-CIRCULANS XYLANASE, beta-glucosidase, CELLULOMONAS-FIMI, glycosidase, IDENTIFICATION, LEAVING GROUP, MECHANISM, REACTION COORDINATE, TRICHODERMA-REESEI},
	isbn = {0006-2960},
	url = {<Go to ISI>://000080165400009},
	author = {Sidhu, G. and Withers, S. G. and Nguyen, N. T. and McIntosh, L. P. and Ziser, L. and Brayer, G. D.}
}
@article {3549,
	title = {PRODUCTION AND PROPERTIES OF A BIFUNCTIONAL FUSION PROTEIN THAT MEDIATES ATTACHMENT OF VERO CELLS TO CELLULOSIC MATRICES},
	journal = {Biotechnology and Bioengineering},
	volume = {47},
	number = {2},
	year = {1995},
	note = {ISI Document Delivery No.: RD894Times Cited: 7Cited Reference Count: 29},
	month = {Jul},
	pages = {147-154},
	type = {Article},
	abstract = {The sequence Arg-Gly-Asp (RGD) in extracellular matrix proteins such as fibronectin, collagen, and laminin mediates cell attachment by interacting with proteins of the integrin family of cell surface receptors. A gene fusion encoding the RGD-containing peptide, fused to the C-terminus of a cellulose-binding domain (CBD/RGD), was expressed in Escherichia coli. Cultures produced up to 50 mg of CBD/RGD per titer, most of which was extracellular. it was purified from the culture supernatant by affinity chromatography on cellulose. CBD/RGD promoted the attachment of green monkey Vero cells to polystyrene and cellulose acetate. Attachment was inhibited by smalt synthetic peptides containing the RGD sequence. CBD/RGD was as effective as collagen in promoting the attachment of Vero cells to Cellsnow(TM) microcarriers. (C) 1995 John Wiley and Sons, Inc.},
	keywords = {ADHESION, ARG-GLY-ASP, BINDING DOMAINS, BIOTECHNOLOGY, CELLULASES, CELLULOMONAS-FIMI, CELLULOSE, CULTURE, FIBRONECTIN, PROTEIN PRODUCTION, SEGMENT, SIGNAL, VITRONECTIN},
	isbn = {0006-3592},
	url = {<Go to ISI>://A1995RD89400004},
	author = {Wierzba, A. and Reichl, U. and Turner, R. F. B. and Warren, R. A. J. and Kilburn, D. G.}
}
