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We have shown recently that PrkC, which is involved in developmental processes in Bacillus subtilis, is a Ser/Thr kinase with features of the receptor kinase family of eukaryotic Hanks kinases. In this study, we expressed and purified from Escherichia coli the cytoplasmic domain of PrkC containing the kinase and a short juxtamembrane region. This fragment, which we designate PrkCc, undergoes autop

Low-energy-electron-diffraction (LEED), scanning-tunneling-microscopy (STM), and photoelectron-spectroscopy measurements have been performed on the ordered submonolayer surface reconstructions of Yb on Si(111). Two of these reconstructions, namely, 3×1 and 2×1, have been studied in detail. STM and LEED revealed that what was considered to be the 3×1 reconstruction is actually a 3×2 reconstruction.

A co-ordinated series of field experiments were conducted to consider the effects of elevated UV-B radiation applied directly to decomposing plant litter. Betula pubescens was decomposed under ambient and elevated UV-B (simulating a 15% ozone depletion) using outdoor irradiation facilities at Adventdalen, Norway (78° N), Abisko, Sweden (68° N), Amsterdam, The Netherlands (52° N,) and Patras, Greec

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

Prospective cohort studies about cutaneous melanoma (CM) risk are still few. Host factor- and UVR exposure data were collected prospectively by questionnaire in this population-based cohort study including 40000 Swedish born women, aged 25-64 years at enrolment (1990). Risk for CM (Cox regression and Stepwise Cox regression [SCR], hazard ratios [HRs] with 95 % Confidence Intervals [CI]) in relatio

Factor I (FI) is a serine protease that inhibits all complement pathways by degrading activated complement components C3b and C4b. FI functions only in the presence of several cofactors such as factor H, C4b-binding protein, complement receptor 1 and membrane cofactor protein. FI is composed of two chains linked by a disulphide bridge; the light chain comprises only the serine protease (SP) domain

Shallow groundwater in unconsolidated sediments represents a substantial water resource in the Chinese Loess Plateau. However, prior to development of the water supply for agriculture, annual and seasonal fluctuation of the recharge mechanism should be clarified. Since the region is arid, the effect of plant water uptake on groundwater fluctuation must also be assessed. A study was therefore under

The specific insertion of a divalent metal ion into tetrapyrrole macrocycles is catalyzed by a group of enzymes called chelatases. Distortion of the tetrapyrrole has been proposed to be an important component of the mechanism of metallation. We present the structures of two different inhibitor complexes: (1) N-methylmesoporphyrin (N-MeMP) with the His183Ala variant of Bacillus subtilis ferrochelat

Ribonucleotide reductases (RNRs) catalyze the reduction of ribonucleotides to deoxyribonucleotides, the building blocks for DNA synthesis, and are found in all but a few organisms. RNRs use radical chemistry to catalyze the reduction reaction. Despite RNR having evolved several mechanisms for generation of different kinds of essential radicals across a large evolutionary time frame, this initial r

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

The identification of unknown genomic flanking DNA sequences can be used for the molecular monitoring of retro-, lenti- and foamyviral integration, transgenes in early embryogenesis, insertional mutagenesis, cell fate, and stem cell plasticity. Most existing methods reflect shortcomings in sensitivity and or specificity, thus limiting genomic sequencing of unknown flanking DNA to clonal preparatio