BACKGROUND The third cytoplasmic loop of rhodopsin (Rho EF) is important in signal transduction from the retinal in rhodopsin to its G protein, transducin. This loop also interacts with rhodopsin kinase, which phosphorylates light-activated rhodopsin, and arrestin, which displaces transducin from light-activated phosphorylated rhodopsin. RESULTS We replaced eight residues of the EF loop of ba...

The proton transfer activity of the light-driven proton pump, bacteriorhodopsin (bR) in the photochemical cycle might imply internal water molecules. The free energy of inserting water molecules in specific sites along the bR transmembrane channel has been calculated using molecular dynamics simulations based on a microscopic model. The existence of internal hydration is related to the free ene...

bacteriorhodopsin operates as a light/proton transfer pump which converts the light energy into a proton gradient. energy stored in the proton gradient can be used in a variety of ways. bacteriorhodopsin producing sources are some halobacterium species such as halobacterium sodomense and halobacterium salinarum which continue to grow in harsh and salt-saturated conditions. two types of red pigm...

Two new surfactants, F5OM and F5DM, were designed as partially fluorinated analogues of n-dodecyl-β-D-maltoside (DDM). The micellization properties the morphologies aggregates formed by two surfactants in water phosphate buffer evaluated NMR spectroscopy, surface tension measurement, isothermal titration calorimetry, dynamic light scattering, small-angle X-ray analytical ultracentrifugation. As...

A Dynamic Nuclear Polarisation (DNP) enhanced solid-state Magic Angle Spinning (MAS) NMR spectrometer which uses a 187 GHz (corresponding to (1)H NMR frequency of 284 MHz) Extended Interaction Klystron (EIK) amplifier as the microwave source is briefly described. Its performance is demonstrated for a biomolecule (bacteriorhodopsin), a pharmaceutical, and surface functionalised silica. The EIK i...

Combined quantum mechanical and molecular mechanical (QM/MM) calculations and molecular dynamics simulations of bacteriorhodopsin (bR) in the membrane matrix have been carried out to determine the factors that make significant contributions to the opsin shift. We found that both solvation and interactions with the protein significantly shifts the absorption maximum of the retinal protonated Sch...

bacteriorhodopsin operates as a light/proton transfer pump which converts the light energy into a proton gradient. energy stored in the proton gradient can be used in a variety of ways. bacteriorhodopsin producing sources are some halobacterium species such as halobacterium sodomense and halobacterium salinarum which continue to grow in harsh and salt-saturated conditions. two types of red pigm...

The aminergic alpha(2b)-adrenergic receptor (alpha(2b)-AR) third intracellular loop (alpha(2b)-AR 3i) mediates receptor subcellular compartmentalization and signal transduction processes via ligand-dependent interaction with G(i)- and G(o)- proteins. To understand the structural origins of these processes we engineered several lengths of alpha(2b)-AR 3i into the third intracellular loop of the ...

Quasielastic incoherent neutron scattering from hydrogen atoms, which are distributed nearly homogeneously in biological molecules, allows the investigation of diffusive motions occurring on the pico- to nanosecond time scale. A quasielastic incoherent neutron scattering study was performed on the integral membrane protein bacteriorhodopsin (BR), which is a light-driven proton pump in Halobacte...