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Spatiotemporal management of solar, wind and hydropower across continental Europe

Weather climate fluctuations cause large variations in renewable electricity production, which requires substantial amounts of energy storage to overcome energy drought periods. Based on daily hydroclimatic data and information about renewable power systems covering Europe, here we quantify the complementarity in the solar-wind-hydro energy components of the continental climate system. We show tha

Artificial intelligence in pediatric allergy research

Atopic dermatitis, food allergy, allergic rhinitis, and asthma are among the most common diseases in childhood. They are heterogeneous diseases, can co-exist in their development, and manifest complex associations with other disorders and environmental and hereditary factors. Elucidating these intricacies by identifying clinically distinguishable groups and actionable risk factors will allow for b

Managing Coronavirus Disease 2019 Spread With Voluntary Public Health Measures : Sweden as a Case Study for Pandemic Control

BACKGROUND: The coronavirus disease 19 (COVID-19) pandemic has spread globally, causing extensive illness and mortality. In advance of effective antiviral therapies, countries have applied different public health strategies to control spread and manage healthcare need. Sweden has taken a unique approach of not implementing strict closures, instead urging personal responsibility. We analyze the res

Female Faculty : Why So Few and Why Care?

Despite slow ongoing progress in increasing the representation of women in academia, women remain significantly under-represented at senior levels, in particular in the natural sciences and engineering. Not infrequently, this is downplayed by bringing forth arguments such as inherent biological differences between genders, that current policies are adequate to address the issue, or by deflecting t

Harnessing Conformational Plasticity to Generate Designer Enzymes

Recent years have witnessed an explosion of interest in understanding the role of conformational dynamics both in the evolution of new enzymatic activities from existing enzymes and in facilitating the emergence of enzymatic activity de novo on scaffolds that were previously non-catalytic. There are also an increasing number of examples in the literature of targeted engineering of conformational d

Modeling the Alkaline Hydrolysis of Diaryl Sulfate Diesters : A Mechanistic Study

Phosphate and sulfate esters have important roles in regulating cellular processes. However, while there has been substantial experimental and computational investigation of the mechanisms and the transition states involved in phosphate ester hydrolysis, there is far less work on sulfate ester hydrolysis. Here, we report a detailed computational study of the alkaline hydrolysis of diaryl sulfate d

Recent Advances in Understanding Biological GTP Hydrolysis through Molecular Simulation

GTP hydrolysis is central to biology, being involved in regulating a wide range of cellular processes. However, the mechanisms by which GTPases hydrolyze this critical reaction remain controversial, with multiple mechanistic possibilities having been proposed based on analysis of experimental and computational data. In this mini-review, we discuss advances in our understanding of biological GTP hy

Short and simple sequences favored the emergence of N-helix phospho-ligand binding sites in the first enzymes

The ubiquity of phospho-ligands suggests that phosphate binding emerged at the earliest stage of protein evolution. To evaluate this hypothesis and unravel its details, we identified all phosphate-binding protein lineages in the Evolutionary Classification of Protein Domains database. We found at least 250 independent evolutionary lineages that bind small molecule cofactors and metabolites with ph

Enzyme Evolution : An Epistatic Ratchet versus a Smooth Reversible Transition

Evolutionary trajectories are deemed largely irreversible. In a newly diverged protein, reversion of mutations that led to the functional switch typically results in loss of both the new and the ancestral functions. Nonetheless, evolutionary transitions where reversions are viable have also been described. The structural and mechanistic causes of reversion compatibility versus incompatibility ther

The role of ligand-gated conformational changes in enzyme catalysis

Structural and biochemical studies on diverse enzymes have highlighted the importance of ligand-gated conformational changes in enzyme catalysis, where the intrinsic binding energy of the common phosphoryl group of their substrates is used to drive energetically unfavorable conformational changes in catalytic loops, from inactive open to catalytically competent closed conformations. However, compu

Uncovering the Role of Key Active-Site Side Chains in Catalysis : An Extended Brønsted Relationship for Substrate Deprotonation Catalyzed by Wild-Type and Variants of Triosephosphate Isomerase

We report results of detailed empirical valence bond simulations that model the effect of several amino acid substitutions on the thermodynamic (ΔG°) and kinetic activation (ΔG⧧) barriers to deprotonation of dihydroxyacetone phosphate (DHAP) and d-glyceraldehyde 3-phosphate (GAP) bound to wild-type triosephosphate isomerase (TIM), as well as to the K12G, E97A, E97D, E97Q, K12G/E97A, I170A, L230A,

GTP Hydrolysis Without an Active Site Base : A Unifying Mechanism for Ras and Related GTPases

GTP hydrolysis is a biologically crucial reaction, being involved in regulating almost all cellular processes. As a result, the enzymes that catalyze this reaction are among the most important drug targets. Despite their vital importance and decades of substantial research effort, the fundamental mechanism of enzyme-catalyzed GTP hydrolysis by GTPases remains highly controversial. Specifically, ho

Relative Binding Energies Predict Crystallographic Binding Modes of Ethionamide Booster Lead Compounds

Transcriptional repressor EthR from Mycobacterium tuberculosis is a valuable target for antibiotic booster drugs. We previously reported a virtual screening campaign to identify EthR inhibitors for development. Two ligand binding orientations were often proposed, though only the top scoring pose was utilized for filtering of the large data set. We obtained biophysically validated hits, some of whi

Cryptic genetic variation shapes the adaptive evolutionary potential of enzymes

Genetic variation among orthologous proteins can cause cryptic phenotypic properties that only manifest in changing environments. Such variation may impact the evolvability of proteins, but the underlying molecular basis remains unclear. Here, we performed comparative directed evolution of four orthologous metallo-β-lactamases toward a new function and found that different starting genotypes evolv

Structural consequence of the most frequently recurring cancer-associated substitution in DNA polymerase ε

The most frequently recurring cancer-associated DNA polymerase ε (Pol ε) mutation is a P286R substitution in the exonuclease domain. While originally proposed to increase genome instability by disrupting exonucleolytic proofreading, the P286R variant was later found to be significantly more pathogenic than Pol ε proofreading deficiency per se. The mechanisms underlying its stronger impact remained

Human Glycerol 3-Phosphate Dehydrogenase : X-ray Crystal Structures That Guide the Interpretation of Mutagenesis Studies

Human liver glycerol 3-phosphate dehydrogenase ( hlGPDH) catalyzes the reduction of dihydroxyacetone phosphate (DHAP) to form glycerol 3-phosphate, using the binding energy associated with the nonreacting phosphodianion of the substrate to properly orient the enzyme-substrate complex within the active site. Herein, we report the crystal structures for unliganded, binary E·NAD, and ternary E·NAD·DH

Loop Motion in Triosephosphate Isomerase Is Not a Simple Open and Shut Case

Conformational changes are crucial for the catalytic action of many enzymes. A prototypical and well-studied example is loop opening and closure in triosephosphate isomerase (TIM), which is thought to determine the rate of catalytic turnover in many circumstances. Specifically, TIM loop 6 "grips" the phosphodianion of the substrate and, together with a change in loop 7, sets up the TIM active site