A series of neomycin dimers have been synthesized using "click chemistry" with varying functionality and length in the linker region to target the human immunodeficiency virus type 1 (HIV-1) TAR RNA region of the HIV virus. The TAR (Trans-Activation Responsive) RNA region, a 59 bp stem-loop structure located at the 5'-end of all nascent viral transcripts, interacts with its target, a key regula...

The normally monomeric 01 subunit of Escherichia coti tryptophan synthetase forms dimers and higher order aggregates following exposure to high urea concentrations and removal of the urea by dialysis. The maximum yield of cx chain dimers is approximately 2%. Dimers of certain combinations of different enzymatically inactive mutant (Y monomers exhibit the missing enzymatic activity. In such hete...

Dimerization-driven activation of the intracellular kinase domains of the epidermal growth factor receptor (EGFR) upon extracellular ligand binding is crucial to cellular pathways regulating proliferation, migration, and differentiation. Inactive EGFR can exist as both monomers and dimers, suggesting that the mechanism regulating EGFR activity may be subtle. The membrane itself may play a role ...

A series of anthraquinone-imide-based dimers, C5 -AQI-Si2, C5 -AQI-Si3, C5 -AQI-Si4, and C5 AQI-Si8, have been prepared by the hydrosilylation of N-(hex-5-enyl)-6-(40-((S)-2-methylbutoxy)phenyl)anthraquinone-2,3-dicarboxylic imide and hydride-terminated siloxanes with different lengths. Their liquid crystalline behaviors, and piezochromic and near-infrared electrochromic properties have been ch...

We show in a joint experimental and theoretical study that ultrafast femto-second (fs) electronic coherences can be characterized semi-conducting colloidal quantum dot (QD) assemblies at room temperature. The dynamics of the response ensembles CdSe QDs solution QD dimers solid state is probed by sequence 3 fs laser pulses as two-dimensional (2D) spectroscopy. computed using an excitonic model H...

Human immunodeficiency virus type 1 (HIV-1) and HIV-2 proteases are dimers of identical subunits. We made a construct for the expression of recombinant one-chain HIV-2 protease dimer, which, like the previously described one-chain HIV-1 protease dimer, is fully active. The constructs for the one-chain dimers of HIV-1 and HIV-2 proteases were modified to produce hybrid one-chain dimers consistin...

Experiments are reported which demonstrate that Na dimers can be desorbed in a non-thermal reaction if rough Na surfaces are irradiated with pulsed laser light of 3, = 355 nm at low laser fluences. This follows from the kinetic-energy distributions of the dimers, which were determined by time-of-flight measurements using a second laser at 1= 248 nm for photoionization. The rate of desorbed dime...

The solid state structures of a number of ortho-substituted arylboronic acids, ortho-bromophenyl, ortho-phenylphenyl, pentamethylphenyl, and 10-bromo-9-anthryl, were determined by X-ray diffraction techniques. All boronic acids investigated form dimers in the solid state, but the interconnection of dimers to ribbons differs from that of the parent phenylboronic acid. Pentamethylphenylboronic ac...

Equilibrium atomic geometries of rhodamine 6G (R6G) dye molecule dimers are studied using density-functional theory. Electron-energy structure and optical properties of R6G H and J dimers are calculated using the generalized gradient approximation method with ab initio pseudopotentials. Our theory predicts substantial redshifts or blueshifts of the optical absorption spectra of R6G dye molecule...

Energy transfer from photo-excited excitons confined in silicon nanoparticles to oxygen dimers adsorbed on the nanoparticle surfaces is studied as a function of temperature and magnetic field. Quenching features in the nanoparticle photoluminescence spectrum arise from energy transfer to the oxygen dimers with and without the emission of Si TO(Δ) phonons and, also, with and without the vibratio...