issue contents
June 2016 issue
research communications
The crystal structure of the DNA-binding domain (DBD) of the transcription regulator MetR from E. coli was solved at 2.16 Å resolution. The DNA-recognition mechanism of the DBD of MetR was explored by macromolecular docking simulations.
PDB reference: DNA-binding domain of MetR, 5fo5
The crystal structure of the TK2203 protein was determined at 1.41 Å resolution.
PDB reference: TK2203 protein, 5hee
Open access
An overview of cyclization strategies of a Fab-binding peptide to maximize affinity.
PDB references: cetuximab Fab with AQFDLSTRRLKA meditope, 5esq; with (AcN)-CQFDLSTRRLKC-(Am) meditope, 5hpm; with CQFDLSTRRLKC-(Am) meditope, 5hyq; with (AcN)-CQFDLSTRRLRCGGSK meditope, 5icx; with SQFDLSTRRLKS meditope, 5icy; with GQFDLSTRRLKG meditope, 5icz; with (AHA)QFDLSTRRLK meditope, 5id0; with (MPT)QFDLSTRRLKC meditope, 5id1
Crystallographic analysis of the putative thioredoxin Trx1 from T. africanus strain TCF52B, which has low sequence identity to its closest homologues, was completed using sulfur single-wavelength anomalous dispersion analysis.
Open access
A structural study of A. thaliana glutamate-1-semialdehyde-2,1-aminomutase (GSAM) has revealed asymmetry in cofactor binding as well as in the gating-loop orientation, which supports the previously proposed negative cooperativity between monomers of GSAM.
PDB reference: AtGSA1, 5hdm
Rv1957 from M. tuberculosis is a SecB-like protein that functions in the higBA toxin–antitoxin system. Here, the crystallization and X-ray crystallographic analysis of Rv1957 are described.
The structure of the first chimaeric glutamate dehydrogenase has been determined at 2.7 Å resolution. This active enzyme was designed from the NADP+-binding domain of the E. coli enzyme and the substrate-binding domain of the enzyme from C. symbiosum.
PDB reference: chimaeric glutamate dehydrogenase, 2yfh
A solute-binding protein from Pfam13407 was found to be specific for D-glucosamine/D-galactosamine by differential scanning fluorimetry and X-ray crystallography.
The structure of the homing endonuclease I-SceI from S. cerevisiae has been determined in complex with its target DNA and catalytic cations, revealing a two-metal-ion mechanism.
The Os01T0156300 protein, a plant-specific DUF1110 protein from O. sativa, was expressed, purified and crystallized. An X-ray diffraction data set was collected from a native crystal to 1.84 Å resolution.
Bacterial VapBC modules belong to the type II toxin–antitoxin systems, which function in many important biological processes, such as the stringent response and drug tolerance. The toxin VapC1 and the cognate antitoxin VapB1 from M. tuberculosis were separately cloned and co-expressed in E. coli BL21(DE3) cells. Diffraction-quality crystals were obtained by using commercial sparse-matrix screen solutions as additives.
Crystal structures are described of two monomeric triosephosphate isomerase (TIM) variants (Ma18, with four point mutations, and Ma21, with one point mutation) that were identified via a directed-evolution protocol (starting from A-TIM) and that have enhanced in vivo L-arabinose isomerase activity. The two structures show that the point mutations cause only minor structural changes, and for Ma21 the small structural changes near Asn11 of loop 1 rationalize its different binding properties.
Open access
In this study, high-resolution structures of both the N-terminal DNA-binding SAP domain and the C-terminal RNA-binding domain of S. cerevisiae Tho1 have been determined.