DNA ligases operating at low temperatures have potential advantages for use in biotechnological applications. For this reason, we have characterized the temperature optima and thermal stabilities of three minimal Lig E-type ATP-dependent DNA ligase originating from Gram-negative obligate psychrophilic bacteria. The three ligases, denoted Vib-Lig, Psy-Lig, and Par-Lig, show a remarkable range of ...

This study was carried out with a view of understanding the temporal dynamics of microcystin concentrations in both algal seston and water samples and the associated public health risk. All the major MC variants, namely MC-LR, MC-YR, and MC-RR, were detected in both the algal seston and water samples. In the majority of the samples, the most potent variant, MC-LR, constituted the greatest proportion ...

We present the novel observation that Duschinsky mixings can lead to the breakdown of Kasha’s rule in a white light phosphor molecule, dibenzo[<i>b,d</i>]thiophen-2-yl (4-chlorophenyl)methanone. Our theoretical analyses show the energy gap between the T₁ and T₂ states (0.48 eV) is too large to allow for any significant population of the T₂ state at room temperature ...

Photo- and thermo- isomerization trajectories of various conversion pathways between nitro-spiropyran and its <i>trans–trans–cis</i> merocyanine form were produced and the role of nπ* states was investigated along the corresponding potential energy surface calculated using the ωB97XD functional and the cc-pVDZ basis set. The nondissociative nπ* states on the photoisomerization trajectories can switch ...

We report a combined experimental-theoretical study on the 31P NMR chemical shift for a number of trans-platinum(II) complexes. Validity and reliability of the 31P NMR chemical shift calculations are examined by comparing with the experimental data. A successful computational protocol for the accurate prediction of the 31P NMR chemical shifts was established for trans-[PtCl2(dma)PPh3] (dma = ...

A combination of quantum chemical calculations and synthetic studies was used to address the possibility of very high (>6) valence states of transition metals in porphyrin‐type complexes. With corrole as a supporting ligand, DFT calculations ruled out Re(VII) and Ir(VII) dioxo complexes as stable species. Attempted rhenium insertion into benzocarbaporphyrin (BCP) ligands on the other hand led to two ...

<i>Background</i> - The discovery of thermostable DNA polymerases such as Taq DNA polymerase revolutionized amplification of DNA by polymerase chain reaction methods that rely on thermal cycling for strand separation. These methods are widely used in the laboratory for medical research, clinical diagnostics, criminal forensics and general molecular biology research. Today there is a growing demand ...

Reduced nitrogen oxide ligands such as NO⁻/HNO or nitroxyl participate in chemistry distinct from nitric oxide (NO). Nitroxyl has been proposed to form at heme centers to generate the Enemark–Feltham designated {FeNO}⁸ system. The synthesis of a thermally stable {FeNO}⁸ species namely, [Co(Cp^*)₂][Fe(LN₄)(NO)] (3), housed in a heme-like ...

The crystal structure of haemoglobin from Atlantic cod has been solved to 2.54 A˚ resolution. The structure consists of two tetramers in the crystallographic asymmetric unit. The structure of haemoglobin obtained from one individual cod suggests polymorphism in the tetrameric assembly.

We present a formulation of relativistic linear response time-dependent density functional theory for the calculation of electronic excitation energies in the framework of the four-component Dirac-Coulomb Hamiltonian. This approach is based on the noncollinear <i>ansatz</i> originally developed by Scalmani and Frisch [J. Chem. Theory Comput. 8, 2193 (2012)] and improves upon the past treatment of ...