The crystal structure of the malic enzyme from aster yellows witches'-broom (Candidatus Phytoplasma) is reported. The structure showcases a minimal scaffold harbouring malic enzyme activity, shedding light on the evolution of complex malic enzymes.

The three-dimensional structure of a human IgA Fab is reported for the first time in three different crystal forms. Compared with a FabG with identical variable domains, the FabA displays a more rigid architecture which can explain the long-distance effects of the constant regions on antigen-binding affinity.

The crystal structure of Rv2714, a protein of unknown function from M. tuberculosis, has been determined at 2.6 Å resolution using single-wavelength anomalous diffraction methods.

Mycobacterial PimA is an essential enzyme that catalyses the first mannosylation step in phosphatidyl-myo-inositol mannoside (PIM) biosynthesis. Crystals of the enzyme from M. smegmatis, obtained in the presence of GDP and myo-inositol, are orthorhombic (P2₁2₁2₁) and diffract X-rays to 2.4 Å resolution.

Glycogen synthase is the enzyme that catalyzes the last step in glycogen biosynthesis. Crystals of the enzyme from the bacterium A. tumefaciens have been obtained that diffract to 2.6 Å resolution and belong to space group P2₁. Selenomethionine has been successfully incorporated, setting the framework for a multiwavelength anomalous diffraction approach.

The crystallization of glucose-6-phosphate dehydrogenase from the human pathogen T. cruzi is reported.

A correction to the article by Ortíz et al. [(2011), Acta Cryst. F67, 1457-1461] .

FcpA from Leptospira interrogans, which is essential for pathogenesis, was crystallized but proved to be recalcitrant to X-ray diffraction studies. The orthologue from the saprophyte L. biflexa allowed three different crystal forms to be obtained that were suitable for crystallographic studies.