Kartlegging av forurensningstilstanden i Meråker gruvefelt

Avrenning fra kisgruvene i Meråkerfeltet påvirker fortsatt vannkvaliteten i vassdragene i nedbørfeltet selv 100 år etter at gruvedriften opphørte. Største forurensningskilde i området er Lillefjell gruve som bidrar med ca. 80 % av kobbertilførslene til Stjørdalselva som er ca. 3 tonn på årsbasis. Gilsåa og Dalåa er mest belastet med tungmetaller, men vassdragsreguleringen som er foretatt, kan ha bidratt til en forverret vannkvalitet i Torsbjørka nedenfor inntaket til kraftverket. Undersøkelser av bunnfaunaen viser klare påvirkninger i Dalåa, mens det var en naturlig bunnfauna i nedre del av Torsbjørka og i Stjørdalselva. Burforsøk med ørret viste en høy dødelighet i Gilsåa/Dalåa. Det ble også påvist at ørreten i Torsbjørka var metallbelastet

NAA10 p.(N101K) disrupts N-terminal acetyltransferase complex NatA and is associated with developmental delay and hemihypertrophy

Nearly half of all human proteins are acetylated at their N-termini by the NatA N-terminal acetyltransferase complex. NAA10 is evolutionarily conserved as the catalytic subunit of NatA in complex with NAA15, but may also have NatA-independent functions. Several NAA10 variants are associated with genetic disorders. The phenotypic spectrum includes developmental delay, intellectual disability, and cardiac abnormalities. Here, we have identified the previously undescribed NAA10 c.303C>A and c.303C>G p.(N101K) variants in two unrelated girls. These girls have developmental delay, but they both also display hemihypertrophy a feature normally not observed or registered among these cases. Functional studies revealed that NAA10 p.(N101K) is completely impaired in its ability to bind NAA15 and to form an enzymatically active NatA complex. In contrast, the integrity of NAA10 p.(N101K) as a monomeric acetyltransferase is intact. Thus, this NAA10 variant may represent the best example of the impact of NatA mediated N-terminal acetylation, isolated from other potential NAA10-mediated cellular functions and may provide important insights into the phenotypes observed in individuals expressing pathogenic NAA10 variants.publishedVersio

Sink i ferskvann - kjemi, tilførsler og biologiske effekter

Det er laget en kunnskapsstatus for betydningen av sink i ferskvann med særlig vekt på tilførsler fra gruveavrenning. I tillegg ble det utført en undersøkelse av biologiske effekter i et vassdrag. Sveselva, med sink-belastning, men få andre metaller. Alle levende organismer har behov for sink, men det er begrensede kunnskaper om mekanismene bak giftigheten til metallet. Effekt-grenser for akvatiske organismer varier fra 10 til over 1000 µg/l. Blant de mest følsomme organismene er enkelte alger, planktoniske krepsdyr og utviklingsstadier hos fisk. I Sveselva var det tilsynelatende effekter på vegetasjon (begroing) allerede ved 20-30 µg/l, men det er usikkert om dette var det reelle belastningsnivået. Både vegetasjon og bunndyr var klart påvirket på stasjoner med konsentrasjoner i området 250-670 µg/l. Kadmium og sink akkumulerte i gjellene til utplassert dammusling på alle stasjoner nedenfor tilførslene og førte til noe forhøyede konsentrasjoner av metallotionein. Dammusling med høye metall-nivåer i gjellene filtrerte mindre alger og hadde høyere respirasjon enn dammusling med lavere metall-nivåer i gjellene. Resultatene viser at det er viktig å benytte flere mål for biologiske effekter i overvåking av effektene av metall-forurensning og å integrere kjemisk og biologisk overvåking

Out of equilibrium correlation functions of quantum anisotropic XY models: one-particle excitations

We calculate exactly matrix elements between states that are not eigenstates of the quantum XY model for general anisotropy. Such quantities therefore describe non equilibrium properties of the system; the Hamiltonian does not contain any time dependence. These matrix elements are expressed as a sum of Pfaffians. For single particle excitations on the ground state the Pfaffians in the sum simplify to determinants.Comment: 11 pages, no figures; revtex. Minor changes in the text; list of refs. modifie

Entanglement and Spontaneous Symmetry Breaking in Quantum Spin Models

It is shown that spontaneous symmetry breaking does not modify the ground-state entanglement of two spins, as defined by the concurrence, in the XXZ- and the transverse field Ising-chain. Correlation function inequalities, valid in any dimensions for these models, are presented outlining the regimes where entanglement is unaffected by spontaneous symmetry breaking

Entanglement and correlation in anisotropic quantum spin systems

Analytical expressions for the entanglement measures concurrence, i-concurrence and 3-tangle in terms of spin correlation functions are derived using general symmetries of the quantum spin system. These relations are exploited for the one-dimensional XXZ-model, in particular the concurrence and the critical temperature for disentanglement are calculated for finite systems with up to six qubits. A recent NMR quantum error correction experiment is analyzed within the framework of the proposed theoretical approach.Comment: 8 pages, 3 figure

Early diverging insect-pathogenic fungi of the order entomophthorales possess diverse and unique subtilisin-like serine proteases

Insect-pathogenic fungi use subtilisin-like serine proteases (SLSPs) to degrade chitin-associated proteins in the insect procuticle. Most insect-pathogenic fungi in the order Hypocreales (Ascomycota) are generalist species with a broad host-range, and most species possess a high number of SLSPs. The other major clade of insect-pathogenic fungi is part of the subphylum Entomophthoromycotina (Zoopagomycota, formerly Zygomycota) which consists of high host-specificity insect-pathogenic fungi that naturally only infect a single or very few host species. The extent to which insect-pathogenic fungi in the order Entomophthorales rely on SLSPs is unknown. Here we take advantage of recently available transcriptomic and genomic datasets from four genera within Entomophthoromycotina: the saprobic or opportunistic pathogens Basidiobolus meristosporus, Conidiobolus coronatus, C. thromboides, C. incongruus, and the host-specific insect pathogens Entomophthora muscae and Pandora formicae, specific pathogens of house flies (Muscae domestica) and wood ants (Formica polyctena), respectively. In total 154 SLSP from six fungi in the subphylum Entomophthoromycotina were identified: E. muscae (n = 22), P. formicae (n = 6), B. meristosporus (n = 60), C. thromboides (n = 18), C. coronatus (n = 36), and C. incongruus (n = 12). A unique group of 11 SLSPs was discovered in the genomes of the obligate biotrophic fungi E. muscae, P. formicae and the saprobic human pathogen C. incongruus that loosely resembles bacillopeptidase F-like SLSPs. Phylogenetics and protein domain analysis show this class represents a unique group of SLSPs so far only observed among Bacteria, Oomycetes and early diverging fungi such as Cryptomycota, Microsporidia, and Entomophthoromycotina. This group of SLSPs is missing in the sister fungal lineages of Kickxellomycotina and the fungal phyla Mucoromyocta, Ascomycota and Basidiomycota fungi suggesting interesting gene loss patterns

Scaling of Entanglement close to a Quantum Phase Transitions

In this Letter we discuss the entanglement near a quantum phase transition by analyzing the properties of the concurrence for a class of exactly solvable models in one dimension. We find that entanglement can be classified in the framework of scaling theory. Further, we reveal a profound difference between classical correlations and the non-local quantum correlation, entanglement: the correlation length diverges at the phase transition, whereas entanglement in general remains short ranged.Comment: 4 pages, 4 figures, revtex. Stylistic changes and format modifie

Characterization of hARD2, a processed hARD1 gene duplicate, encoding a human protein N-α-acetyltransferase

BACKGROUND: Protein acetylation is increasingly recognized as an important mechanism regulating a variety of cellular functions. Several human protein acetyltransferases have been characterized, most of them catalyzing ε-acetylation of histones and transcription factors. We recently described the human protein acetyltransferase hARD1 (human Arrest Defective 1). hARD1 interacts with NATH (N-Acetyl Transferase Human) forming a complex expressing protein N-terminal α-acetylation activity. RESULTS: We here describe a human protein, hARD2, with 81 % sequence identity to hARD1. The gene encoding hARD2 most likely originates from a eutherian mammal specific retrotransposition event. hARD2 mRNA and protein are expressed in several human cell lines. Immunoprecipitation experiments show that hARD2 protein potentially interacts with NATH, suggesting that hARD2-NATH complexes may be responsible for protein N-α-acetylation in human cells. In NB4 cells undergoing retinoic acid mediated differentiation, the level of endogenous hARD1 and NATH protein decreases while the level of hARD2 protein is stable. CONCLUSION: A human protein N-α-acetyltransferase is herein described. ARD2 potentially complements the functions of ARD1, adding more flexibility and complexity to protein N-α-acetylation in human cells as compared to lower organisms which only have one ARD

NatF Contributes to an Evolutionary Shift in Protein N-Terminal Acetylation and Is Important for Normal Chromosome Segregation

N-terminal acetylation (N-Ac) is a highly abundant eukaryotic protein modification. Proteomics revealed a significant increase in the occurrence of N-Ac from lower to higher eukaryotes, but evidence explaining the underlying molecular mechanism(s) is currently lacking. We first analysed protein N-termini and their acetylation degrees, suggesting that evolution of substrates is not a major cause for the evolutionary shift in N-Ac. Further, we investigated the presence of putative N-terminal acetyltransferases (NATs) in higher eukaryotes. The purified recombinant human and Drosophila homologues of a novel NAT candidate was subjected to in vitro peptide library acetylation assays. This provided evidence for its NAT activity targeting Met-Lys- and other Met-starting protein N-termini, and the enzyme was termed Naa60p and its activity NatF. Its in vivo activity was investigated by ectopically expressing human Naa60p in yeast followed by N-terminal COFRADIC analyses. hNaa60p acetylated distinct Met-starting yeast protein N-termini and increased general acetylation levels, thereby altering yeast in vivo acetylation patterns towards those of higher eukaryotes. Further, its activity in human cells was verified by overexpression and knockdown of hNAA60 followed by N-terminal COFRADIC. NatF's cellular impact was demonstrated in Drosophila cells where NAA60 knockdown induced chromosomal segregation defects. In summary, our study revealed a novel major protein modifier contributing to the evolution of N-Ac, redundancy among NATs, and an essential regulator of normal chromosome segregation. With the characterization of NatF, the co-translational N-Ac machinery appears complete since all the major substrate groups in eukaryotes are accounted for