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Cobalt-Catalyzed Asymmetric Hydrogenation of Enamides: Insights into Mechanisms and Solvent Effects
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-07-25)The mechanistic details of the (<sup>Ph</sup>BPE)Co-catalyzed asymmetric hydrogenation of enamides are investigated using computational and experimental approaches. Four mechanistic possibilities are compared: a direct Co(0)/Co(II) redox path, a metathesis pathway, a nonredox Co(II) mechanism featuring an azametallacycle, and a possible enamide−imine tautomerization pathway. The results indicate ... -
Cold shock induction of recombinant Arctic environmental genes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-19)Background: Heterologous expression of psychrophilic enzymes in E. coli is particularly challenging due to their intrinsic instability. The low stability is regarded as a consequence of adaptation that allow them to function at low temperatures. Recombinant production presents a significant barrier to their exploitation for commercial applications in industry. <p>Methods: As part of an enzyme ... -
Combination of adsorption/desorption and photocatalytic reduction processes for PFOA removal from water by using an aminated biosorbent and a UV/sulfite system
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-17)Per- and polyfluoroalkyl substances (PFAS) are stable organic chemicals, which have been used globally since the 1940s and have caused PFAS contamination around the world. This study explores perfluorooctanoic acid (PFOA) enrichment and destruction by a combined method of sorption/desorption and photocatalytic reduction. A novel biosorbent (PG-PB) was developed from raw pine bark by grafting amine ... -
A combined quantum mechanics/molecular mechanics study of the one- and two-photon absorption in the green fluorescent protein
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012-02-01)We present for the first time a QM/MM study of the one- and two-photon absorption spectra of the GFP chromophore embedded in the full protein environment described by an advanced quantum mechanically derived polarizable force field. The calculations are performed on a crystal structure of the green fluorescent protein (GFP) using the polarizable embedding density functional theory (PE-DFT) scheme. ... -
Communication: The absolute shielding scales of oxygen and sulfur revisited
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03-04)We present an updated semi-experimental absolute shielding scale for the 17O and 33S nuclei. These new shielding scales are based on accurate rotational microwave data for the spin–rotation constants of H2 17O [Puzzarini et al., J. Chem. Phys. 131, 234304 (2009)], C17O [Cazzoli et al., Phys. Chem. Chem. Phys. 4, 3575 (2002)], and H2 33S [Helgaker et al., J. Chem. Phys. 139, 244308 (2013)] ... -
Comparative analysis of HiSeq3000 and BGISEQ-500 sequencing platform with shotgun metagenomic sequencing data
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-29)Recent advances in sequencing technologies and platforms have enabled to generate metagenomics sequences using different sequencing platforms. In this study, we analyzed and compared shotgun metagenomic sequences generated by HiSeq3000 and BGISEQ-500 platforms from 12 sediment samples collected across the Norwegian coast. Metagenomics DNA sequences were normalized to an equal number of bases for ... -
Comparative conformational analyses and molecular dynamics studies of glycylglycine methyl ester and glycylglycine N -methylamide
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-24)Compared to their amide analogs, peptidic esters have a lower propensity for intramolecular hydrogen bonding, and thus most likely quite different stable geometries. On the other hand, their similarity and facile conversion to peptides has led to their broad use in synthetic and biological applications. This dichotomy creates a need to understand their conformational properties. Here, we study the ... -
Comparative study of CO2 insertion into pincer supported palladium alkyl and aryl complexes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-12)The insertion of CO2 into metal alkyl bonds is a crucial elementary step in transition metal-catalyzed processes for CO2 utilization. Here, we synthesize pincer-supported palladium complexes of the type (tBuPBP)Pd(alkyl) (tBuPBP = B(NCH2PtBu2)2C6H4−; alkyl = CH2CH3, CH2CH2CH3, CH2C6H5, and CH2-4-OMe-C6H4) and (tBuPBP)Pd(C6H5) and compare the rates of CO2 insertion into the palladium alkyl bonds to ... -
A comparative study of cold-and warmadapted Endonucleases A using sequence analyses and molecular Dynamics simulations
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-02-13)The psychrophilic and mesophilic endonucleases A (EndA) from Aliivibrio salmonicida (VsEndA) and Vibrio cholera (VcEndA) have been studied experimentally in terms of the biophysical properties related to thermal adaptation. The analyses of their static X-ray structures was no sufficient to rationalize the determinants of their adaptive traits at the molecular level. Thus, we used Molecular Dynamics ... -
A comparative theoretical study on core-hole excitation spectra of azafullerene and its derivatives
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014) -
Comparing Isoelectronic, Quadruple-Bonded Metalloporphyrin and Metallocorrole Dimers: Scalar-Relativistic DFT Calculations Predict a > 1-eV Range for Ionization Potential and Electron Affinity
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-21)A scalar-relativistic DFT study of isoelectronic, quadruple-bonded Group 6 metalloporphyrins (M = Mo, W) and Group 7 metallocorroles (M = Tc, Re) has uncovered dramatic differences in ionization potential (IP) and electron affinity (EA) among the compounds. Thus, both the IPs and EAs of the corrole derivatives are 1 eV or more higher than those of the porphyrin derivatives. These differences ... -
Comparison of 2- and 3-compartment electrodialytic remediation cells for oil polluted soil from northwest Russia
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-08)Electrodialytic remediation is a method based on electrokinetics, in which an electric field of low intensity increases the availability of pollutants in solid waste materials. The electric field induces processes that mobilise and transport inorganic and organic pollutants. The transport of ions in the electrodialytic cell is controlled by employing ion-exchange membranes, allowing separation of ... -
Comparison of 2-compartment, 3-compartment and stack designs for electrodialytic removal of heavy metals from harbour sediments
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-11-01)Comparisons of cell and stack designs for the electrodialytic removal of heavy metals from two harbour sediments, were made. Multivariate modelling showed that sediment properties and experimental set-ups had the highest influence on the heavy metal removal indicating that they should be modelled and analysed separately. Clean-up levels of Cu, Pb and Zn were significantly higher for the cell designs, ... -
Complete analytic anharmonic hyper-Raman scattering spectra
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-07-11)We present the first computational treatment of the complete second-order vibrational perturbation theory applied to hyper-Raman scattering spectroscopy. The required molecular properties are calculated in a fully analytic manner using a recently developed program [Ringholm, Jonsson and Ruud, J. Comp. Chem., 2014, 35, 622] that utilizes recursive routines. For some of the properties, these ... -
Complete genome sequence of Halomonas sp. R5-57
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016)The marine Arctic isolate Halomonas sp. R5-57 was sequenced as part of a bioprospecting project which aims to discover novel enzymes and organisms from low-temperature environments, with potential uses in biotechnological applications. Phenotypically, Halomonas sp. R5-57 exhibits high salt tolerance over a wide range of temperatures and has extra-cellular hydrolytic activities with several ... -
Complete genome sequence of Photobacterium ganghwense C2.2: A new polyhydroxyalkanoate production candidate
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-01)Polyhydroxyalkanoates (PHAs) are biodegradable bioplastics that can be manufactured sustainably and represent a promising green alternative to petrochemical-based plastics. Here, we describe the complete genome of a new marine PHA-producing bacterium—Photobacterium ganghwense (strain C2.2), which we have isolated from the Black Sea seashore. This new isolate is psychrotolerant and accumulates PHA ... -
Complete genome sequence of Vibrio anguillarum strain NB10, a virulent isolate from the Gulf of Bothnia
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-02)Vibrio anguillarum causes a fatal hemorrhagic septicemia in marine fish that leads to great economical losses in aquaculture world-wide. Vibrio anguillarum strain NB10 serotype O1 is a Gram-negative, motile, curved rod-shaped bacterium, isolated from a diseased fish on the Swedish coast of the Gulf of Bothnia, and is slightly halophilic. Strain NB10 is a virulent isolate that readily colonizes ... -
Complete Genome Sequences of Seven Vibrio anguillarum Strains as Derived from PacBio Sequencing
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-04-07)We report here the complete genome sequences of seven Vibrio anguillarum strains isolated from multiple geographic locations, thus increasing the total number of genomes of finished quality to 11. The genomes were de novo assembled from long-sequence PacBio reads. Including draft genomes, a total of 44 V. anguillarum genomes are currently available in the genome databases. They represent an important ... -
The complex structures of isocitrate dehydrogenase from Clostridium thermocellum and Desulfotalea psychrophila support a new active site locking mechanism
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012-07-07)Isocitrate dehydrogenase (IDH) catalyzes the oxidative NAD(P)+ -dependent decarboxylation of isocitrate into a-ketoglutarate and CO2 and is present in organisms spanning the biological range of temperature. We have solved two crystal structures of the thermophilic Clostridium thermocellum IDH (CtIDH), a native open apo CtIDH to 2.35 Å and a quaternary complex of CtIDH with NADP+ , isocitrate and ... -
Computational and experimental insights into asymmetric Rh‐catalyzed hydrocarboxylation with CO2
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-18)The asymmetric Rh‐catalyzed hydrocarboxylation of α,β‐unsaturated carbonyl compounds was originally developed by Mikami and co‐workers but gives only moderate enantiomeric excesses. In order to understand the factors controlling the enantioselectivity and to propose novel ligands for this reaction, we have used computational and experimental methods to study the Rh‐catalyzed hydrocarboxylation with ...