Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Chemistry
Effect Of Surface Charges On The Rates Of Intermolecular Electron-Transfer Between De Novo Designed Metalloproteins, Anna Y. Kornilova, James F. Wishart, Michael Y. Ogawa
Effect Of Surface Charges On The Rates Of Intermolecular Electron-Transfer Between De Novo Designed Metalloproteins, Anna Y. Kornilova, James F. Wishart, Michael Y. Ogawa
Chemistry Faculty Publications
A de novo designed coiled-coil metalloprotein was prepared that uses electrostatic interactions to control both its conformational and bimolecular electron-transfer properties. The title protein exists as a coiled-coil heterodimer of the [Ru(trpy)(bpy)-KK(37-mer)] and [Ru(NH3)(5)-EE(37-mer)] polypeptides which is formed by interhelix electrostatic attractions. Circular dichroism studies show that the electrostatic heterodimer has Kd 0.19 +/- 0.03 muM and is 96% helical at high concentrations. Intercomplex electron-transfer reactions were studied that involve the [Ru(NH3)(5)-H21](2+) electron-donor and the [Ru(trpy)(bpy)H21](3+) electron-acceptor belonging to different electrostatic dimers. An important feature of the designed metalloprotein is its two cationic redox centers embedded within protein surfaces having …
Infrared Spectroscopy Of H-Bonded Bridges Stretched Across The Cis-Amide Group: Ii. Ammonia And Mixed Ammonia/Water Bridges, A. V. Fedorov, John R. Cable, Joel R. Carney, Timothy S. Zwier
Infrared Spectroscopy Of H-Bonded Bridges Stretched Across The Cis-Amide Group: Ii. Ammonia And Mixed Ammonia/Water Bridges, A. V. Fedorov, John R. Cable, Joel R. Carney, Timothy S. Zwier
Chemistry Faculty Publications
Clusters of two model cis amides, oxindole and 3,4-dihydro-2(IH)-quinolinone, containing one and two ammonia molecules have been studied in the IR hydride stretch region using resonant ion-dip IR spectroscopy. The spectra confirm that ammonia is able to form hydrogen-bonded bridges across the adjacent amide N-H and C=O sites in a manner very similar to that of water. Such bridged structures require that ammonia assume the role of a hydrogen bond donor. Further similarities of the hydrogen bonding capabilities of ammonia and water have been revealed by investigations of ternary clusters containing an amide, one ammonia, and one water molecule. Experimentally, …
Infrared Spectroscopy Of H-Bonded Bridges Stretched Across The Cis-Amide Group: I. Water Bridges, Joel R. Carney, A. V. Fedorov, John R. Cable, Timothy S. Zwier
Infrared Spectroscopy Of H-Bonded Bridges Stretched Across The Cis-Amide Group: I. Water Bridges, Joel R. Carney, A. V. Fedorov, John R. Cable, Timothy S. Zwier
Chemistry Faculty Publications
The water-containing clusters of oxindole (OI) and 3,4-dihydro-2(1H)-quinolinone (DQ) have been studied in the hydride stretch region of the infrared by the technique of resonant ion-dip infrared spectroscopy (RIDIRS). Both OI and DQ are constrained cis-amides with adjacent N-H and C=O groups between which water can form H-bonded bridges. The hydride stretch fundamentals of OI-W-n with n = 1-3 and DQ-W-n with n = 1, 2 without exception divide up into free OH stretch fundamentals near 3700 cm(-1) and a set of H-bonded bridge fundamentals in the 3200-3450 cm(-1) region. The bridge fundamentals show a distribution of intensities that reflects …
Tectorna: Modular Assembly Units For The Construction Of Rna Nano-Objects, Neocles B. Leontis, Luc Jaeger, Eric Westhof
Tectorna: Modular Assembly Units For The Construction Of Rna Nano-Objects, Neocles B. Leontis, Luc Jaeger, Eric Westhof
Chemistry Faculty Publications
Structural information on complex biological RNA molecules can be exploited to design tectoRNAs or artificial modular RNA units that can self-assemble through tertiary interactions thereby forming nanoscale RNA objects. The selective interactions of hairpin tetraloops with their receptors can be used to mediate tectoRNA assembly. Here we report on the modulation of the specificity and the strength of tectoRNA assembly tin the nanomolar to micromolar range) by variation of the length of the RNA subunits, the nature of their interacting motifs and the degree of flexibility of linker regions incorporated into the molecules. The association is also dependent on the …