Among the ultimate goals of protein physics, the complete, experimental description of the energy paths leading to protein conformational changes remains a challenge. Single protein fluorescence spectroscopy constitutes an approach of choice for addressing protein dynamics, and, among naturally fluorescing proteins, light-harvesting (LH) proteins from purple bacteria constitute an ideal object ...

It was shown decades ago that purified 30S ribosome subunits readily interconvert between "active" and "inactive" conformations in a switch that involves changes in the functionally important neck and decoding regions. However, the physiological significance of this conformational change had remained unknown. In exponentially growing Escherichia coli cells, RNA SHAPE probing revealed that 16S r...

Thermal conformational changes in human serum albumin (HSA) in present with a 10 mM phosphate buffer, at pH=7 have been investigated via circular dichroism (CD) and UV spectroscopic methods. The results indicate that temperature in a range of 25oC to 55oC could induce a reversible conformational change in the structure of HSA. The HSA phase transition corresponds to the physiological and patho...

Structures of three cocrystals nootropic racetams were studied. They included two phenylpiracetam (PPA) with 4-hydroxybenzoic acid (HBA) different stoichiometries, PPA·HBA and PPA·2HBA, cocrystal 2-(4-phenyl-2-oxopyrrolidin-1-yl)-N’-isopropylideneacetohydrazide (PPAH) 4-hydroxybenzamide (HBD), PPAH·HBD·(acetone solvate). X-ray study the pure forms PPA PPAH was also carried out to identify varia...

background: there are two subclasses of human iga (iga1 and iga2) that differ in antigenic properties and in chemical composition. the constant domains of α1 and α2 heavy chains have >95% sequence homology though major structural differences exist in the hinge region. quantitation of iga subclass levels depends on the availability of monoclonal antibodies (mabs) specific for conserved conformat...

background: varicocele is associated with the failure of ipsilateral testicular growth and development, and the symptoms of pain and reduced fertility. the highly condensed structure of the sperm nuclear chromatin is provided by proper expression of transition nuclear protein (tnp) genes, so any dysregulational expression of these genes results in abnormal spermatogenesis and infertility. objec...