The level set of an elliptic function is a doubly periodic point set in C. To obtain a wider spectrum of point sets, we consider, more generally, a Riemann surface S immersed in C2 and its sections (“cuts”) by C. We give S a crystallographic isometry in C2 by defining a fundamental surface element as a conformal map of triangular domains and S as its extension by reflections in the triangle edg...

x Ray crystallography is currently the most favoured technique for structure determination of proteins and biological macromolecules. Increasingly, those interested in all branches of the biological sciences require structural information to shed light on previously unanswered questions. Furthermore, the availability of a protein structure can provide a more detailed focus for future research. ...

The first fully automated small-molecule robotic X-ray diffractometer is described. After demonstrating the utility of the instrument using multiple samples of ammonium bitartrate, we investigated the conformational chirality of diphenyl dichalcogenide (E(2)Ph(2), where E = S, Se, or Te). Structural and computational studies suggest that the two enantiomers are energetically indistinguishable. ...

Serial femtosecond X-ray crystallography (SFX) has created new opportunities in the field of structural analysis of protein nanocrystals. The intensity and timescale characteristics of the X-ray free-electron laser sources used in SFX experiments necessitate the analysis of a large collection of individual crystals of variable shape and quality to ultimately solve a single, average crystal stru...

The reported data describe the crystallization, crystal packing, structure determination and twinning of the unliganded Fab (antigen-binding fragment) from the NISTmAb (standard reference material 8671). The raw atomic coordinates are available as Protein Data Bank structure 5K8A and biological aspects are described in the article, (Karageorgos et al., 2017) [1]. Crystal data show that the pack...

Applications of structural databases in the protein crystallographic structure determination process are reviewed, using mostly examples from work carried out by the authors. Four application areas are discussed: model building, model refinement, model validation and model analysis.

X-ray free-electron lasers produce brief flashes of X-rays that are of about a billion times higher peak brightness than achievable from storage ring sources. Such a tremendous jump in X-ray source capabilities, that came in 2009 when the Linac Coherent Light Source begun operations, was unprecedented in the history of X-ray science. Protein structure determination through the method of macromo...