issue contents
August 2017 issue
research communications
Open access
The crystal structure of the plasmid-mediated colistin resistance determinant MCR-2 has been determined at 1.12 Å resolution. This high-resolution structure highlights the molecular diversity of clinically relevant MCR proteins and provides an accurate starting model for further mechanistic, and in particular computational, studies.
PDB reference: MCR-2 catalytic domain, 5mx9
Archaic Csu pili mediate the formation of A. baumannii biofilms on abiotic surfaces. To determine the structural basis for biofilm formation, native and selenomethionine-substituted pilus tip adhesin subunit CsuE complexed with the chaperone CsuC was produced in E. coli, purified and crystallized. Methylation of lysine residues was essential for crystallization of the complex. Initial phases were derived from selenomethionine-based single-wavelength anomalous dispersion.
The antitoxin GraA from P. putida and its complexes with the toxin GraT and with the 33 bp operator of the graTA operon were crystallized.
The crystal structure of Hcp2 from S. typhimurium and its oligomeric state in solution are reported.
PDB reference: Hcp2 from S. typhimurium, 5xeu
Its haematophagic habits and urban habitat make the mosquito Aedes aegypti an important vector of a number of human viruses. Here, the high-resolution crystal structure of AaTI, a noncanonical Kazal inhibitor from the saliva of A. aegypti, is presented, providing a molecular explanation for its inhibitory profile.
A lactonase from Alicyclobacter acidoterrestris named AaL has been isolated, purified, characterized and crystallized. The structure of AaL is expected to provide insights regarding its catalytic mechanism of lactone hydrolysis.
The dynamic, filament-formation features of the DREP4 CIDE domain were characterized. The filament-like DREP4 CIDE domain was purified and crystallized in space group P212121, with unit-cell parameters a = 53.08, b = 76.58, c = 174.59 Å; the crystals diffracted to a resolution of 1.9 Å.
The two amino-terminal LU domains of C4.4A were excised by limited proteolysis and were crystallized using the sitting-drop vapour-diffusion method. The crystals diffracted to 2.7 Å resolution, giving good-quality data.
Open access
M. domestica polyphenol oxidase 1 (MdPPO1) was recombinantly expressed in its latent form (Lys1–Ser504) and successfully mutated at four different positions around the active centre which have been proposed to be decisive for the activity of the enzyme. The wild-type MdPPO1 and two of the mutants were successfully crystallized. In crystallo activity tests demonstrated the importance of these amino acids for the activity of the enzyme.