The signaling state of the photoactive yellow protein (PYP) photoreceptor is transiently developed via isomerization of its blue-light-absorbing chromophore. The associated structural rearrangements have large amplitude but, due to its transient nature and chemical exchange reactions that complicate NMR detection, its accurate three-dimensional structure in solution has been elusive. Here we re...

Small angle x-ray scattering (SAXS) is a valuable method for studying structure changes which take place during phase transitions in polymeric and oligomeric systems. Measurements of the dependence of SAXS on temperature yield information on the changes in morphology or of the structure on a supermolecular level. The technique can be applied to various problems: glass transition in highly cryst...

Ultra-SAXS can enhance the capabilities of existing SAXS/WAXS beamlines and laboratory instruments. A compact module has been developed, which extends measurable $q$-range with $0.0015 \leq q\mathrm{(nm^{-1})} 0.2$, allowing structural dimensions between $30 D$(nm)$ 4000$ to be probed in addition range covered by a high-end instrument. By shifting components out on their respective motor stages...

A procedure is presented for refinement of a homology model of E. coli tRNA(Val), originally based on the X-ray structure of yeast tRNA(Phe), using experimental residual dipolar coupling (RDC) and small angle X-ray scattering (SAXS) data. A spherical sampling algorithm is described for refinement against SAXS data that does not require a globbic approximation, which is particularly important fo...