β-Mannosidase (EC 3.2.1.25) is an important exoglycosidase specific for the hydrolysis of terminal β-linked mannoside in various oligomeric saccharide structures. β-Mannosidase from Aspergillus niger was expressed in Pichia pastoris and purified to clear homogeneity. β-Mannosidase was crystallized in the presence of D-mannose and the crystal diffracted to 2.41 Å resolution. The crystal belonged to space group P1, with unit-cell parameters a=62.37, b=69.73, c=69.90 Å, α=108.20, β=101.51, γ=103.20°. The parameters derived from the data collection indicate the presence of one molecule in the asymmetric unit.
- MeSH
- Aspergillus niger chemie enzymologie MeSH
- beta-mannosidasa chemie genetika MeSH
- fungální proteiny chemie genetika MeSH
- krystalizace MeSH
- krystalografie rentgenová MeSH
- mannosa chemie MeSH
- Pichia chemie genetika MeSH
- rekombinantní proteiny chemie genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Haloalkane dehalogenases are microbial enzymes that convert a broad range of halogenated aliphatic compounds to their corresponding alcohols by the hydrolytic mechanism. These enzymes play an important role in the biodegradation of various environmental pollutants. Haloalkane dehalogenase LinB isolated from a soil bacterium Sphingobium japonicum UT26 has a relatively broad substrate specificity and can be applied in bioremediation and biosensing of environmental pollutants. The LinB variants presented here, LinB32 and LinB70, were constructed with the goal of studying the effect of mutations on enzyme functionality. In the case of LinB32 (L117W), the introduced mutation leads to blocking of the main tunnel connecting the deeply buried active site with the surrounding solvent. The other variant, LinB70 (L44I, H107Q), has the second halide-binding site in a position analogous to that in the related haloalkane dehalogenase DbeA from Bradyrhizobium elkanii USDA94. Both LinB variants were successfully crystallized and full data sets were collected for native enzymes as well as their complexes with the substrates 1,2-dibromoethane (LinB32) and 1-bromobutane (LinB70) to resolutions ranging from 1.6 to 2.8 Å. The two mutants crystallize differently from each other, which suggests that the mutations, although deep inside the molecule, can still affect the protein crystallizability.
- MeSH
- bakteriální proteiny chemie genetika metabolismus MeSH
- biodegradace MeSH
- bromované uhlovodíky chemie metabolismus MeSH
- Escherichia coli chemie genetika MeSH
- ethylendibromid chemie metabolismus MeSH
- hydrolasy chemie genetika metabolismus MeSH
- izoenzymy chemie genetika metabolismus MeSH
- krystalizace MeSH
- krystalografie rentgenová MeSH
- rekombinantní proteiny chemie genetika metabolismus MeSH
- Sphingomonadaceae chemie enzymologie genetika MeSH
- substrátová specifita MeSH
- vazebná místa MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Histidine-containing phosphotransfer proteins from Arabidopsis thaliana (AHP1-5) act as intermediates between sensor histidine kinases and response regulators in a signalling system called multi-step phosphorelay (MSP). AHP proteins mediate and potentially integrate various MSP-based signalling pathways (e.g. cytokinin or osmosensing). However, structural information about AHP proteins and their importance in MSP signalling is still lacking. To obtain a deeper insight into the structural basis of AHP-mediated signal transduction, the three-dimensional structure of AHP2 was determined. The AHP2 coding sequence was cloned into pRSET B expression vector, enabling production of AHP2 fused to an N-terminal His tag. AHP2 was expressed in soluble form in Escherichia coli strain BL21 (DE3) pLysS and then purified to homogeneity using metal chelate affinity chromatography and anion-exchange chromatography under reducing conditions. Successful crystallization in a buffer which was optimized for thermal stability yielded crystals that diffracted to 2.5 Å resolution.
- MeSH
- Arabidopsis metabolismus MeSH
- difrakce rentgenového záření MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- fosfotransferasy chemie izolace a purifikace MeSH
- krystalizace MeSH
- proteiny huseníčku chemie izolace a purifikace MeSH
- signální transdukce * MeSH
- tranzitní teplota MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Haloalkane dehalogenases are hydrolytic enzymes with a broad range of potential practical applications such as biodegradation, biosensing, biocatalysis and cellular imaging. Two newly isolated psychrophilic haloalkane dehalogenases exhibiting interesting catalytic properties, DpcA from Psychrobacter cryohalolentis K5 and DmxA from Marinobacter sp. ELB17, were purified and used for crystallization experiments. After the optimization of crystallization conditions, crystals of diffraction quality were obtained. Diffraction data sets were collected for native enzymes and complexes with selected ligands such as 1-bromohexane and 1,2-dichloroethane to resolutions ranging from 1.05 to 2.49 Å.
The bacterial enzyme organophosphorus acid anhydrolase (OPAA) is able to catalyze the hydrolysis of both proline dipeptides (Xaa-Pro) and several types of organophosphate (OP) compounds. The full three-dimensional structure of the manganese-dependent OPAA enzyme is presented for the first time. This enzyme, which was originally isolated from the marine bacterium Alteromonas macleodii, was prepared recombinantly in Escherichia coli. The crystal structure was determined at 1.8 Å resolution in space group C2, with unit-cell parameters a = 133.8, b = 49.2, c = 97.3 Å, β = 125.0°. The enzyme forms dimers and their existence in solution was confirmed by dynamic light scattering and size-exclusion chromatography. The enzyme shares the pita-bread fold of its C-terminal domain with related prolidases. The binuclear manganese centre is located in the active site within the pita-bread domain. Moreover, an Ni(2+) ion from purification was localized according to anomalous signal. This study presents the full structure of this enzyme with complete surroundings of the active site and provides a critical analysis of its relationship to prolidases.
- MeSH
- Alteromonas enzymologie MeSH
- aryldialkylfosfatasa chemie MeSH
- dipeptidasy chemie MeSH
- kvarterní struktura proteinů MeSH
- lidé MeSH
- molekulární modely MeSH
- molekulární sekvence - údaje MeSH
- sekvence aminokyselin MeSH
- sekvenční seřazení MeSH
- terciární struktura proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The structure of the H107R variant of the extracellular domain of the mouse natural killer cell receptor NKR-P1A has been determined by X-ray diffraction at 2.3 Å resolution from a merohedrally twinned crystal. Unlike the structure of the wild-type receptor in space group I4(1)22 with a single chain per asymmetric unit, the crystals of the variant belonged to space group I4(1) with a dimer in the asymmetric unit. Different degrees of merohedral twinning were detected in five data sets collected from different crystals. The mutation does not have a significant impact on the overall structure, but led to the binding of an additional phosphate ion at the interface of the molecules.
- MeSH
- extracelulární prostor chemie MeSH
- krystalografie rentgenová MeSH
- kvarterní struktura proteinů MeSH
- lektinové receptory NK-buněk - podrodina B chemie genetika MeSH
- molekulární modely MeSH
- mutace MeSH
- myši MeSH
- terciární struktura proteinů MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The endonuclease TBN1 from Solanum lycopersicum (tomato) was expressed in Nicotiana benthamiana leaves and purified with suitable quality and in suitable quantities for crystallization experiments. Two crystal forms (orthorhombic and rhombohedral) were obtained and X-ray diffraction experiments were performed. The presence of natively bound Zn2+ ions was confirmed by X-ray fluorescence and by an absorption-edge scan. X-ray diffraction data were collected from the orthorhombic (resolution of 5.2 Å) and rhombohedral (best resolution of 3.2 Å) crystal forms. SAD, MAD and MR methods were applied for solution of the phase problem, with partial success. TBN1 contains three Zn2+ ions in a similar spatial arrangement to that observed in nuclease P1 from Penicillium citrinum.
- MeSH
- deoxyribonukleasy chemie genetika MeSH
- ionty chemie MeSH
- konformace proteinů MeSH
- krystalizace MeSH
- krystalografie rentgenová MeSH
- molekulární sekvence - údaje MeSH
- rekombinantní proteiny chemie genetika MeSH
- rostlinné proteiny chemie genetika MeSH
- Solanum lycopersicum chemie genetika MeSH
- zinek chemie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The paper reports the structure of the small laccase from Streptomyces coelicolor determined from a crystal soaked with potassium hexacyanoferrate [K4Fe(CN)6]. The decolorization of the natively blue crystal observed upon soaking indicates the reduction of the enzyme in the crystal. The ligand binds between laccase molecules and stabilizes the crystal. The increased diffraction limit of the diffraction data collected from this crystal enabled the refinement of the small laccase structure at 2.3 Å resolution, which is the highest resolution obtained to date.
- MeSH
- bakteriální proteiny chemie MeSH
- barva MeSH
- ferrikyanidy chemie MeSH
- konformace proteinů MeSH
- krystalografie rentgenová MeSH
- lakasa chemie MeSH
- měď chemie MeSH
- molekulární modely MeSH
- molekulární sekvence - údaje MeSH
- stabilita enzymů MeSH
- Streptomyces coelicolor enzymologie MeSH
- vazebná místa MeSH
- železo chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Fungal β-N-acetylhexosaminidases are enzymes that are used in the chemoenzymatic synthesis of biologically interesting oligosaccharides. The enzyme from Aspergillus oryzae was produced and purified from its natural source and crystallized using the hanging-drop vapour-diffusion method. Diffraction data from two crystal forms (primitive monoclinic and primitive tetragonal) were collected to resolutions of 3.2 and 2.4 Å, respectively. Electrophoretic and quantitative N-terminal protein-sequencing analyses confirmed that the crystals are formed by a complete biologically active enzyme consisting of a glycosylated catalytic unit and a noncovalently attached propeptide.
Haloalkane dehalogenases hydrolyze carbon-halogen bonds in a wide range of halogenated aliphatic compounds. The potential use of haloalkane dehalogenases in bioremediation applications has stimulated intensive investigation of these enzymes and their engineering. The mutant DhaA31 was constructed to degrade the anthropogenic compound 1,2,3-trichloropropane (TCP) using a new strategy. This strategy enhances activity towards TCP by decreasing the accessibility of the active site to water molecules, thereby promoting formation of the activated complex. The structure of DhaA31 will help in understanding the structure-function relationships involved in the improved dehalogenation of TCP. The mutant protein DhaA31 was crystallized by the sitting-drop vapour-diffusion technique and crystals of DhaA31 in complex with TCP were obtained using soaking experiments. Both crystals belonged to the triclinic space group P1. Diffraction data were collected to high resolution: to 1.31 Å for DhaA31 and to 1.26 Å for DhaA31 complexed with TCP.
- MeSH
- bakteriální proteiny chemie genetika metabolismus MeSH
- difrakce rentgenového záření MeSH
- hydrolasy chemie genetika metabolismus MeSH
- krystalizace MeSH
- molekulární sekvence - údaje MeSH
- propan analogy a deriváty chemie metabolismus MeSH
- Rhodococcus enzymologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
