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Model catalysts containing disordered CuO and ZnO species in the pores of SBA-15 were reduced under different conditions (standard: H2, 513 K; severe: CO/H2, 673 K), studied by X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) including operando work and used as catalysts for methanol synthesis at pressures up to 8 bar, where they were comparable with a commercial reference in terms

M1 aminopeptidases comprise a large family of biologically important zinc enzymes. We show that peptide turnover by the M1 prototype, leukotriene A4 hydrolase/aminopeptidase, involves a shift in substrate position associated with exchange of zinc coordinating groups, while maintaining the overall coordination geometry. The transition state is stabilized by residues conserved among M1 members and i

Nitric oxide (NO) can modulate both tumor growth and antitumor immune responses. In order to elucidate the mechanism of curative therapeutic immunization with IFNgamma-producing glioma cells, we examined the expression of inducible nitric oxide synthase (iNOS) in tissue sections from immunized animals. There was a significantly enhanced iNOS expression both intratumorally and at the immunization s

Leukotriene ( LT) A(4) hydrolase is a bifunctional zinc metalloenzyme, which converts LTA(4) into the neutrophil chemoattractant LTB4 and also exhibits an anion-dependent aminopeptidase activity. In the x-ray crystal structure of LTA(4) hydrolase, Arg(563) and Lys(565) are found at the entrance of the active center. Here we report that replacement of Arg(563), but not Lys(565), leads to complete a

The maximum light use efficiency (LUE = gross primary production (GPP)/absorbed photosynthetic photon flux density (aPPFD)) of plant canopies has been reported to vary spatially and some of this variation has previously been attributed to plant species differences. The canopy nitrogen concentration [N] can potentially explain some of this spatial variation. However, the current paradigm of the N-e

We performed ultrasound measurements (QUS) of the calcaneus in a population-based setting on 280 healthy children, aged 11-16 years, from a small urban area in southern Sweden. The results are compared with dual-energy X-ray absorptiometry (DXA) measurements in the total body, the lumbar spine and the hip, as well as single-energy X-ray absorptiometry (SXA) of the forearm. Normative data and corre

The X-ray structures of dUTPase from equine infectious anaemia virus (EIAV) in unliganded and complexed forms have been determined to 1.9 and 2.0 A resolution, respectively. The structures were solved by molecular replacement using Escherichia coli dUTPase as search model. The exploitation of a relatively novel refinement approach for the initial model, combining maximum likelihood refinement with

Abstract in UndeterminedSoil microbes constitute an important control on nitrogen (N) turnover and retention in arctic ecosystems where N availability is the main constraint on primary production. Ectomycorrhizal (ECM) symbioses may facilitate plant competition for the specific N pools available in various arctic ecosystems. We report here our study on the N uptake patterns of coexisting plants an

Scots pine tree-ring width (TRW) data from Jamtland in the Central Scandinavian Mountains has been used to reconstruct summer temperatures back to 1630 BC. However, it was recently shown that this reconstruction was of limited spatial importance. In this paper, we aim to explain this limitation in the TRW data as a temperature proxy, as well as assess the temperature information from new maximum l

Protein C (PC) is activated to an essential anticoagulant enzyme (activated PC or APC) by thrombin (T) bound to thrombomodulin (TM), a membrane receptor present on the surface of endothelial cells. The understanding of this complex biological system is in part limited due to the lack of integration of experimental and structural data. In the work presented here, we analyze the PC-T-TM pathway in t

Apolipoprotein RI (apoM) is a novel apolipoprotein that is predominantly present in high-density lipoprotein, Sensitive sequence starches, threading and comparative model building experiments revealed apoM to be structurally related to the lipocalin protein family. In a 3D model, characterized by an eight-stranded anti-parallel beta -barrel, a segment including Asn135 could adopt a closed or open

Background - Although effective coverage of challenging coronary lesions has warranted the use of overlapping drug-eluting stents, the histopathological response to stent overlap is unknown. Methods and Results - The arterial reaction to overlapping Cypher or Taxus drug-eluting stents was examined in rabbits with bare metal stents, BxVelocity or Express, serving as controls. Single iliac artery ba