Publications by authors named "Welinder K"

In this article, we present mass-spectrometry based plasma proteomics data from hibernating and active free-ranging Scandinavian brown bears (). The brown bear hibernates for half the year. Despite obesity when entering the den and the prolonged period of inactivity, the bear shows no signs of the harmful effects associated with these conditions in humans.

View Article and Find Full Text PDF

Purpose: Three aspects of the RayPilot real-time tracking system were investigated: (1) feasibility of the transmitter with respect to implantation and explantation procedures, (2) user and patients' experiences and (3) quantification of the transmitter positional stability in relation to fiducial markers.

Methods And Materials: Ten prostate cancer patients scheduled for radiotherapy received transmitter implantation in the prostate, concomitantly with fiducial markers. Transmitter and marker positions were assessed in 3D by orthogonal kV-imaging at daily treatment setup in eight patients.

View Article and Find Full Text PDF

Physical inactivity increases the risk of thromboembolism. However, good standardized human models on inactivity are in short supply and experimental models are few. Our objective was to investigate how standardized bed rest affects platelet aggregation in humans and to investigate if aggregation is altered in a translational model system - the hibernating brown bear (Ursus arctos).

View Article and Find Full Text PDF

Brown bears (Ursus arctos) hibernate for 5-7 months without eating, drinking, urinating, and defecating at a metabolic rate of only 25% of the summer activity rate. Nonetheless, they emerge healthy and alert in spring. We quantified the biochemical adaptations for hibernation by comparing the proteome, metabolome, and hematological features of blood from hibernating and active free-ranging subadult brown bears with a focus on conservation of health and energy.

View Article and Find Full Text PDF

Cereal purple acid phosphatase-type phytases, PAPhy, play an essential role in making phosphate accessible to mammalian digestion and reducing the environmental impact of manure. Studying the potential of PAPhy requires easy access to the enzymes. For that purpose wheat and barley isophytases have been expressed in Pichia pastoris from constructs encoding the alpha-mating factor at the N-termini and a His₆ tag before the stop codon in all constructs.

View Article and Find Full Text PDF

Potato tuber storage proteins were obtained from vacuoles isolated from field-grown starch potato tubers cv. Kuras. Vacuole sap proteins fractionated by gel filtration were studied by mass spectrometric analyses of trypsin and chymotrypsin digestions.

View Article and Find Full Text PDF

Phytase activity in grain is essential to make phosphate available to cell metabolism, and in food and feed. Cereals contain the purple acid phosphatase type of phytases (PAPhy). Mature wheat grain is dominated by TaPAPhy_a which, in the present work, has been characterized by extensive peptide and glycopeptide sequencing by mass spectrometry.

View Article and Find Full Text PDF

Barley (Hordeum vulgare) and wheat (Triticum aestivum) possess significant phytase activity in the mature grains. Maize (Zea mays) and rice (Oryza sativa) possess little or virtually no preformed phytase activity in the mature grain and depend fully on de novo synthesis during germination. Here, it is demonstrated that wheat, barley, maize, and rice all possess purple acid phosphatase (PAP) genes that, expressed in Pichia pastoris, give fully functional phytases (PAPhys) with very similar enzyme kinetics.

View Article and Find Full Text PDF

Paramagnetic (13)C and (15)N nuclear magnetic resonance (NMR) spectroscopy of heme-bound cyanide ((13)C(15)N) was applied to 11 cytochrome c peroxidase (CcP) and Coprinus cinereus peroxidase (CIP) mutants to investigate contributions to the push and pull effects of conserved amino acids around heme. The (13)C and (15)N NMR data for the distal His and Arg mutants indicated that distal His is the key amino acid residue creating the strong pull effect and that distal Arg assists. The mutation of distal Trp of CcP to Phe, the amino acid at this position in CIP, changed the push and pull effects so they resembled those of CIP, whereas the mutation of distal Phe of CIP to Trp changed this mutant to become CcP-like.

View Article and Find Full Text PDF

Proteome data of potato (Solanum tuberosum) tuber juice and of purified potato tuber vacuoles indicated that mature patatins may perhaps lack a C-terminal propeptide. We have confirmed this by complete mass spectrometric sequencing of a number of patatin variants as well as their N-linked complex-type glycans from the starch-rich cultivar Kuras. For this cultivar full-length patatin cDNAs have also been sequenced, as the patatin locus is highly polymorphous.

View Article and Find Full Text PDF

Potato (Solanum tuberosum) is the fourth largest crop worldwide in yield, and cv. Kuras is the major starch potato of northern Europe. Storage starch is packed densely in tuber amyloplasts, which become starch granules.

View Article and Find Full Text PDF

Background: During gene expression analysis by Serial Analysis of Gene Expression (SAGE), duplicate ditags are routinely removed from the data analysis, because they are suspected to stem from artifacts during SAGE library construction. As a consequence, naturally occurring duplicate ditags are also removed from the analysis leading to an error of measurement.

Results: An algorithm was developed to analyze the differential occurrence of SAGE tags in different ditag combinations.

View Article and Find Full Text PDF

Solanum tuberosum (potato) is the fourth major crop worldwide and is used for food, feed and biotechnological applications. To fully realize the biosynthetic potential for the production of starch, protein and metabolites, we conducted an extensive quantitative profiling of the expressed genes of mature potato tuber. A total of 58,322 serial analysis of gene expression (SAGE) tags of 19 nucleotides (nt), representing 22,233 different tags, were analysed.

View Article and Find Full Text PDF

Potato starch production leaves behind a huge amount of juice. This juice is rich in protein, which might be exploited for food, biotechnological, and pharmaceutical applications. In northern Europe cv.

View Article and Find Full Text PDF

In heme peroxidases, a distal His residue plays an essential role in the initial two electron oxidation of resting state enzyme to compound I by hydrogen peroxide. A distal Arg residue assists in this process. The contributions of the charge, H-bonding capacity, size, and mobility of this Arg residue to Coprinus cinereus peroxidase (CIP) reactivity and stability have been examined by substituting Arg51 with Gln (retains H-bond donor at N epsilon position), Asn (small size, H-bond donor and acceptor), Leu (similar to Asn, but hydrophobic), and Lys (charge and H-bond donor, but at N zeta position).

View Article and Find Full Text PDF

The major potato tuber proteins of the Kuras cultivar, which is the dominant cultivar used in Northern Europe for industrial starch production, were analysed using 1D and 2D gel electrophoresis. The electrophoretic patterns varied significantly depending on the method of preparation and the potato variant (Solanum tuberosum). Proteins were characterized using MS and scored against potato protein databases, derived from both 'Kuras only' and 'all potato' expressed sequence tags (EST) and full-length cDNAs.

View Article and Find Full Text PDF

Significant identification of proteins by mass fingerprinting and partial sequencing of tryptic peptides is central to proteomics. However, peptide masses cluster with distances of approximately 1 Da. Expanding these clusters will give more peptides of unique masses, thereby identifying proteins with a higher significance.

View Article and Find Full Text PDF

The Virtual Expert Mass Spectrometrist (VEMS) program package was developed for flexible, automated, and manual de novo tandem mass spectrometry (MS/MS) protein sequencing, and includes accessory programs for matrix-assisted laser desorption/ionization-mass spectrometry (MS) interpretation, and generation of protein and peptide databases. VEMS V2.0 has been developed into a fast tool for combining database-independent and -dependent protein assignments in an extended analysis of MS/MS-peptide data.

View Article and Find Full Text PDF

Peroxidase from soybean seed coat (SBP) is very stable at high temperature, extremes of pH, and in organic solvent. At the same time, it is highly reactive towards both organic and inorganic substrates, similar to horseradish peroxidase. SBP has a wide range of potential applications, and its structure is of particular interest for engineering purposes and as a model for stable heme peroxidases.

View Article and Find Full Text PDF

The 73 class III peroxidase genes in Arabidopsis thaliana were used for surveying the evolutionary relationships among peroxidases in the plant kingdom. In Arabidopsis, the 73 genes were clustered in robust similarity groups. Comparison to peroxidases from other angiosperms showed that the diversity observed in Arabidopsis preceded the radiation of dicots, whereas some clusters were absent from grasses.

View Article and Find Full Text PDF

Most existing Mass Spectra (MS) analysis programs are automatic and provide limited opportunity for editing during the interpretation. Furthermore, they rely entirely on publicly available databases for interpretation. VEMS (Virtual Expert Mass Spectrometrist) is a program for interactive analysis of peptide MS/MS spectra imported in text file format.

View Article and Find Full Text PDF

The pH dependence of the redox potentials and kinetics for CO association and dissociation was determined between pH 3.0 and 13.0 at 25 degrees C for the wild-type Coprinus cinereus fungal peroxidase and for a site-directed mutant in which Asp245, which is H-bonded to N delta of the imidazole of the proximal His183, was substituted with Asn.

View Article and Find Full Text PDF

Understanding peroxidase function in plants is complicated by the lack of substrate specificity, the high number of genes, their diversity in structure and our limited knowledge of peroxidase gene transcription and translation. In the present study we sequenced expressed sequence tags (ESTs) encoding novel heme-containing class III peroxidases from Arabidopsis thaliana and annotated 73 full-length genes identified in the genome. In total, transcripts of 58 of these genes have now been observed.

View Article and Find Full Text PDF

Resonance Raman and infrared spectra and the CO dissociation rates (k(off)) were measured in Coprinus cinereus peroxidase (CIP) and several mutants in the heme binding pocket. These mutants included the Asp245Asn, Arg51Leu, Arg51Gln, Arg51Asn, Arg51Lys, Phe54Trp, and Phe54Val mutants. Binding of CO to CIP produced different CO adducts at pH 6 and 10.

View Article and Find Full Text PDF