One of the most important overall parameters, which can be derived from smallangle X-ray scattering (SAXS) experiments on macromolecular solutions is the molecular mass (MM) of the solute. In particular, for a monodisperse protein solution, MM of the solute is calculated from the extrapolated scattering intensity at zero angle I(0). Assessing MM by SAXS provides valuable information about the o...

The application of small-angle X-ray scattering (SAXS) to structural investigations of transmembrane proteins in detergent solution has been hampered by two main inherent hurdles. On the one hand, the formation of a detergent corona around the hydrophobic region of the protein strongly modifies the scattering curve of the protein. On the other hand, free micelles of detergent without a precisel...

A comparative study using small-angle x-ray scattering ~SAXS! and nitrogen adsorption has been carried out in the structural characterization of silica xerogels and aerogels, obtained from tetraethoxysilane sonohydrolysis. The specific surface and the mean pore size as measured by both the techniques were found to be in notable agreement in all cases for aerogels and xerogels. According to the ...

Arlaud et al. (1) raised concerns regarding our smallangle X-ray scattering (SAXS) and EM models of the unbound C1r2s2 tetramer (2). They reference studies supporting an interaction of two C1rs dimers via C1r CCP1–serine protease (SP) interactions. In response, we conducted refinements against our SAXS data by imposing distance restraints derived from C1r CCP1CCP2-SP crystal structures (3, 4). ...

We examine the crystallization and chain conformation behavior of semicrystalline poly(ethylene oxide) (PEO) and amorphous poly(vinyl acetate) (PVAc) mixtures with wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS), and small-angle neutron scattering (SANS) experiments. For blends with PEO weight fractions (wtPEO) greater than or equal to 0.3, below the melting point of PE...

The amyloid precursor protein (APP) is the precursor of the beta-amyloid peptide (Abeta), which is centrally related to the genesis of Alzheimer's disease (AD). In addition, APP has been suggested to mediate and/or participate in events that lead to neuronal degeneration in AD. Despite the fact that various aspects of the cell biology of APP have been investigated, little information on the str...

For the (coherent) small-angle X-ray scattering (SAXS) beamline X12SA of the Swiss Light Source at the Paul Scherrer Institut, a novel X-ray detector is built, the PILATUS 2M. Contributions in module fabrication, detector assembly, characterization and calibration are covered within the framework of this thesis. Furthermore, data analysis of a particular SAXS experiment demonstrating the perfor...

We present an investigation of β-lactoglobulin adsorption onto spherical polyelectrolyte brushes (SPBs) by small angle X-ray scattering (SAXS). The SPB consists of a polystyrene core onto which long chains of poly(styrene sulfonate) are grafted. The amount and the distribution of proteins adsorbed in the brush layer at low ionic strength can be derived from SAXS. The analysis of the SAXS data r...

Determination of the 3D structures of multidomain proteins by solution NMR methods presents a number of unique challenges related to their larger molecular size and the usual scarcity of constraints at the interdomain interface, often resulting in a decrease in structural accuracy. In this respect, experimental information from small-angle scattering of X-ray radiation in solution (SAXS) presen...

(Cytosine-5)-DNA methyltransferase SsoII (M.SsoII) consists of a methyltransferase domain (residues 72-379) and an N-terminal region (residues 1-71) which regulates transcription in SsoII restriction-modification system. Small-angle X-ray scattering (SAXS) is employed here to study the low resolution structure of M.SsoII and its complex with DNA containing the methylation site. The shapes recon...