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Expanding the Catalytic Triad in Epoxide Hydrolases and Related Enzymes

Potato epoxide hydrolase 1 exhibits rich enantio- and regioselectivity in the hydrolysis of a broad range of substrates. The enzyme can be engineered to increase the yield of optically pure products as a result of changes in both enantio- and regioselectivity. It is thus highly attractive in biocatalysis, particularly for the generation of enantiopure fine chemicals and pharmaceuticals. The presen

Exceptionally large entropy contributions enable the high rates of GTP hydrolysis on the ribosome

Protein synthesis on the ribosome involves hydrolysis of GTP in several key steps of the mRNA translation cycle. These steps are catalyzed by the translational GTPases of which elongation factor Tu (EF-Tu) is the fastest GTPase known. Here, we use extensive computer simulations to explore the origin of its remarkably high catalytic rate on the ribosome and show that it is made possible by a very l

Development and Application of a Nonbonded Cu2+ Model That Includes the Jahn-Teller Effect

Metal ions are both ubiquitous to and crucial in biology. In classical simulations, they are typically described as simple van der Waals spheres, making it difficult to provide reliable force field descriptions for them. An alternative is given by nonbonded dummy models, in which the central metal atom is surrounded by dummy particles that each carry a partial charge. While such dummy models alrea

Navigating Uncertainty: The Family Perspective of Preparing for Crisis with a Disability

Family disaster planning and preparation demands proactive acknowledgment and accommodation of individuals with disabilities. This study, based on interviews with families including members with disabilities, uncovers insights on information gaps, adaptive strategies, technology use, and support networks. Contributing to disaster and disability studies, resilience, and crisis planning, it highligh

Theoretical modelling of epigenetically modified DNA sequences

We report herein a set of calculations designed to examine the effects of epigenetic modifications on the structure of DNA. The incorporation of methyl, hydroxymethyl, formyl and carboxy substituents at the 5-position of cytosine is shown to hardly affect the geometry of CG base pairs, but to result in rather larger changes to hydrogen-bond and stacking binding energies, as predicted by dispersion

Resolving apparent conflicts between theoretical and experimental models of phosphate monoester hydrolysis

Understanding phosphoryl and sulfuryl transfer is central to many biochemical processes. However, despite decades of experimental and computational studies, a consensus concerning the precise mechanistic details of these reactions has yet to be reached. In this work we perform a detailed comparative theoretical study of the hydrolysis of p-nitrophenyl phosphate, methyl phosphate and p-nitrophenyl

How valence bond theory can help you understand your (bio)chemical reaction

Almost a century has passed since valence bond (VB) theory was originally introduced to explain covalent bonding in the H2 molecule within a quantum mechanical framework. The past century has seen constant improvements in this theory, with no less than two distinct Nobel prizes based on work that is essentially developments in VB theory. Additionally, ongoing advances in both methodology and compu

Energetics of activation of GTP hydrolysis on the ribosome

Several of the steps in protein synthesis on the ribosome utilize hydrolysis of guanosine triphosphate (GTP) as the driving force. This reaction is catalyzed by translation factors that become activated upon binding to the ribosome. The recently determined crystal structure of an elongation factor-Tu ternary complex bound to the ribosome allows the energetics of GTP activation to be explored by co

Computational Study of the pKa Values of Potential Catalytic Residues in the Active Site of Monoamine Oxidase B

Monoamine oxidase (MAO), which exists in two isozymic forms, MAO A and MAO B, is an important flavoenzyme responsible for the metabolism of amine neurotransmitters such as dopamine, serotonin, and norepinephrine. Despite extensive research effort, neither the catalytic nor the inhibition mechanisms of MAO have been completely understood. There has also been dispute with regard to the protonation s

Empirical valence bond simulations of the hydride transfer step in the monoamine oxidase B catalyzed metabolism of dopamine

Monoamine oxidases (MAOs) A and B are flavoenzymes responsible for the metabolism of biogenic amines such as dopamine, serotonin and noradrenaline. In this work, we present a comprehensive study of the rate-limiting step of dopamine degradation by MAO B, which consists in the hydride transfer from the methylene group of the substrate to the flavin moiety of the FAD prosthetic group. This article b

Modeling catalytic promiscuity in the alkaline phosphatase superfamily

In recent years, it has become increasingly clear that promiscuity plays a key role in the evolution of new enzyme function. This finding has helped to elucidate fundamental aspects of molecular evolution. While there has been extensive experimental work on enzyme promiscuity, computational modeling of the chemical details of such promiscuity has traditionally fallen behind the advances in experim

Dissecting Dopaminergic Neuron Specification at Single Cell Resolution - Insights from 3D brain organoids and xenograft models

Midbrain dopaminergic neurons exhibit a wide diversity in their projection patterns, disease vulnerability, and functions, playing key roles in voluntary motor control, cognition, and reward processing. Parkinson’s Disease, one of the most common neurodegenerative disorders, is characterized by the selective degeneration of the A9 dopaminergic neuron subtype, leading to severe motor dysfunction. D

Theoretical comparison of p-nitrophenyl phosphate and sulfate hydrolysis in aqueous solution : implications for enzyme-catalyzed sulfuryl transfer

Both phosphoryl and sulfuryl transfers are ubiquitous in biology, being involved in a wide range of processes, ranging from cell division to apoptosis. Additionally, it is becoming increasingly clear that enzymes that can catalyze phosphoryl transfer can often cross-catalyze sulfuryl transfer (and vice versa). However, while there have been extensive experimental and theoretical studies performed

Association between bullying victimization and obsessive-compulsive disorder : a population-based, genetically informative study

The extent to which bullying victimization is associated with an increased risk of obsessive-compulsive disorder (OCD) has received little empirical attention. This longitudinal, population-based, genetically informative study examined whether self-reported bullying victimization at age 15 was associated with a clinical diagnosis of OCD in the Swedish National Patient Register and with self-report

Transverse dynamics of charmed hadrons in ultra-relativistic nuclear collisions

Transverse momentum pT spectra and anisotropic flow distributions are studied for charmonia and charmed hadrons produced in Pb-Pb collisions and measured with the ALICE detector at the CERN Large Hadron Collider (LHC). The investigations are performed within the framework of the Statistical Hadronization Model with the transverse dynamics evaluated using predictions from relativistic viscous hydro

Projected health benefits of air pollution reductions in a Swedish population

Background: A large part of the Swedish population is exposed to higher levels of air pollution than the health-centered air quality guidelines recommended by the World Health Organization (WHO). Aim: The aim of the study was to illustrate the potential health benefits of cleaner air in Sweden by conducting a comprehensive health impact assessment, using a population sample of 100,000 individuals

Inter-rater variability in multidisciplinary team meetings of oesophageal and gastro-oesophageal junction cancer on staging, resectability and treatment recommendation : national retrospective multicentre study

Background: There are differences in oesophageal cancer care across Sweden. According to national guidelines, all patients should be offered equal care, planned and administrated by regional multidisciplinary team meetings. The aim of the study was to investigate differences between regional multidisciplinary team meetings in Sweden regarding clinical staging and treatment recommendations for oeso