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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

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

Despite the abundance of membrane-associated enzymes, the mechanism by which membrane binding stabilizes these enzymes and stimulates their catalysis remains largely unknown. Serum paraoxonase-1 (PON1) is a lipophilic lactonase whose stability and enzymatic activity are dramatically stimulated when associated with high-density lipoprotein (HDL) particles. Our mutational and structural analyses, co

The polymerization of amino acids into proteins occurs on ribosomes, with the rate influenced by the amino acids being polymerized. The imino acid proline is a poor donor and acceptor for peptide-bond formation, such that translational stalling occurs when three or more consecutive prolines (PPP) are encountered by the ribosome. In bacteria, stalling at PPP motifs is rescued by the elongation fact

Background: Bark beetles are major pests of conifer forests, and their behavior is primarily mediated via olfaction. Targeting the odorant receptors (ORs) may thus provide avenues towards improved pest control. Such an approach requires information on the function of ORs and their interactions with ligands, which is also essential for understanding the functional evolution of these receptors. Henc

TRPV2 is a ligand-operated temperature sensor with poorly defined pharmacology. Here, we combine calcium imaging and patch-clamp electrophysiology with cryo-electron microscopy (cryo-EM) to explore how TRPV2 activity is modulated by the phytocannabinoid Δ9-tetrahydrocannabiorcol (C16) and by probenecid. C16 and probenecid act in concert to stimulate TRPV2 responses including histamine release from

Secondary organic aerosol (SOA) plays a significant role in climate change by altering the global atmospheric radiation budget. Biogenic volatile organic compounds (BVOCs) are major sources for the formation of SOA. Their relationship is critical to understand the continental biosphere-aerosol-cloud-climate (COBACC) feedback mechanism but receives less attention in previous studies. In this study,

Objective: To study whether locally administered recombinant inactivated human coagulation factor VIIa (FFR-rFVIIa) would reduce the thrombus formation and improve patency in an experimental venous thrombosis model without inducing systematic changes in the coagulation. Design: Experimental double-dummy randomised study. Materials: In 20 healthy New Zealand White rabbits both juguIar veins were ex

Purpose: This study explores how information on air pollution is shaped online on an everyday basis, with a particular emphasis on digital devices and digital representations as constitutive of environmental information practices. Furthermore, this research highlights an understudied aspect of air pollution – the digital flow of multimodal representations that citizens encounter and produce in the

Prekallikrein, the precursor to the serine proteinase kailikrein, circulates in plasma in an equimolar complex with H-kininogen. The binding to H-kininogen is mediated by the kallikrein heavy chain consisting of four "apple" domains, A1-A4, which attaches to H-kininogen with high specificity and affinity (KD = 83 UM). At least two distinct portions of the kallikrein heavy chain form this H-kininog

Geosmin is one of the most recognizable and common microbial smells on the planet. Some insects, like mosquitoes, require microbial-rich environments for their progeny, whereas for other insects such microbes may prove dangerous. In the vinegar fly Drosophila melanogaster, geosmin is decoded in a remarkably precise fashion and induces aversion, presumably signaling the presence of harmful microbes

Protein S is a vitamin K-dependent plasma protein. It functions as a cofactor to activated protein C in the inactivation of factors Va and VIIIa by limited proteolysis. Protein S is very sensitive to proteolysis by thrombin which reduces its calcium ion binding and leads to a loss of its cofactor activity. We have now determined the sequence of the 100 amino-terminal amino acid residues and locali

Proteins carrying genetically attached polyhistidine tails have been purified using affinity precipitation with metal chelates. DNA fragments encoding four or five histidine residues have been genetically fused to the oligomeric enzymes lactate dehydrogenase (Bacillus stearothermophilus), beta-glucoronidase (Escherichia coli), and galactose dehydrogenase (Pseudomonas fluorescens) as well as to the

The design of an in vitro immunization system based on a synthetic heterotope immunogen, which was a peptide containing both T- and B-cell epitopes, that elicited a neutralizing, primary human humoral immune response against the human immunodeficiency virus (HIV-1) is reported here. This heterotope construct contained the major neutralizing B-cell epitope, within the V3 region of glycoprotein 120