issue contents
July 2017 issue
research communications
Open access
The high-resolution crystal structure of a complex of the lactonohydrolase zearalenone hydrolase with the hydrolytic product of the oestrogenic myotoxin zearalenone provides information on the final stage of the catalytic mechanism.
ACHT1 from A. thaliana was crystallized and X-ray diffraction data were collected for crystallographic analysis.
β-Aminopeptidases are enzymes with the unique ability to hydrolyze N-terminal β-amino acids from synthetic β-peptides. Here, the crystal structure of a β-aminopeptidase isolated from a Burkholderia sp., BcA5-BapA, is reported. The BcA5-BapA structure shows a tetrameric arrangement, with each monomer adopting a four-layered αββα fold. Comparison with three characterized β-aminopeptidases shows that variation in the substrate-binding pockets may provide the basis for substrate specificity.
PDB reference: BcA5-bapA, 5tzb
The DNA-binding domain of myelin-gene regulatory factor has been expressed, purified and crystallized. A molecular-replacement solution could not be found using its closest known homologous structure and the selenium-substituted crystals have been generated for Se-SAD phasing and structure determination.
Open access
The crystal structure of the catalytic domain of a glycoside hydrolase family 6 cellobiohydrolase from the basidiomycete P. chrysosporium was solved in apo and cellobiose-liganded forms at 1.2 and 2.1 Å resolution, respectively.
As a rescue strategy for crystallization, reductive methylation of lysine residues was performed for a lipid-free form of full-length NisI. Only methylated NisI crystallized readily, and an X-ray diffraction data set was collected to 1.9 Å resolution.
Open access
The purification, reconstitution and crystallization of a complex of F. novicida Cpf1 with CRISPR RNA and target DNA is described.
Open access
Although the enzymatic activity of cytochrome c oxidase (CcO) depends sensitively on pH over a wide range, X-ray structure analyses of bovine CcO have been conducted using crystals prepared at pH 5.7 owing to difficulty in crystallizing this protein. Here, oxidized CcO at pH 7.3 was successfully crystallized using a fluorinated octyl-maltoside derivative, and the structure was determined at 1.77 Å resolution.
PDB reference: bovine heart cytochrome c oxidase, 5xdq
The multidrug-resistance transporter MdfA is able to eject a wide variety of compounds from the cytoplasm of E. coli. As it is an integral membrane protein, obtaining diffraction-quality crystals remains a challenge. Here, it is shown that LCP crystallization results in superior crystal packing to vapour diffusion, and that LCP lipid chain-length variation has a marked effect on the morphology and diffraction behaviour of crystals of MdfA in complex with the Fab fragment YN1074.
In this work, the crystal structure of the N-terminal domain of VqsR (VqsR-N) was determined at 2.1 Å resolution. Structural comparison demonstrated that VqsR-N has a similar structural fold and conserved enclosed cavity to those observed in the LuxR family of acyl-homoserine lactone (AHL) receptors. Structural analyses show that VqsR could be a potential AHL receptor.
PDB reference: N-terminal domain of VqsR, 5xhx
The cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the protein MSMEG_0129 from M. smegmatis are described.