Mechanical energy, specifically in the form of ultrasound, can induce pressure variations and temperature fluctuations when applied to an aqueous media. These conditions can both positively and negatively affect protein complexes, consequently altering their stability, folding patterns, and self-assembling behavior. Despite much scientific progress, our current understanding of the effects of ultrasound on the self-assembly of amyloidogenic proteins remains limited.
View Article and Find Full Text PDFUnlabelled: Mechanical energy, specifically in the form of ultrasound, can induce pressure variations and temperature fluctuations when applied to an aqueous media. These conditions can both positively and negatively affect protein complexes, consequently altering their stability, folding patterns, and self-assembling behavior. Despite much scientific progress, our current understanding of the effects of ultrasound on the self-assembly of amyloidogenic proteins remains limited.
View Article and Find Full Text PDFIn eukaryotes, many DNA/RNA-binding proteins possess intrinsically disordered regions (IDRs) with large negative charge, some of which involve a consecutive sequence of aspartate (D) or glutamate (E) residues. We refer to them as D/E repeats. The functional role of D/E repeats is not well understood, though some of them are known to cause autoinhibition through intramolecular electrostatic interaction with functional domains.
View Article and Find Full Text PDFIntroduction: Designer benzodiazepines (DBs) are a subclass of novel psychoactive substances (NPS). DBs mimic the properties of approved and prescribed benzodiazepines.
Area Covered: A systematic search of literature on DB classification, structure-activity relationships, pharmacologic properties, and adverse effects.
Highly negatively charged segments containing only aspartate or glutamate residues ("D/E repeats") are found in many eukaryotic proteins. For example, the C-terminal 30 residues of the HMGB1 protein are entirely D/E repeats. Using nuclear magnetic resonance (NMR), fluorescence, and computational approaches, we investigated how the D/E repeats causes the autoinhibition of HMGB1 against its specific binding to cisplatin-modified DNA.
View Article and Find Full Text PDFDNA-binding proteins rely on linear diffusion along the longitudinal DNA axis, supported by their nonspecific electrostatic affinity for DNA, to search for their target recognition sites. One may therefore expect that the ability to engage in linear diffusion along DNA is universal to all DNA-binding proteins, with the detailed biophysical characteristics of that diffusion differing between proteins depending on their structures and functions. One key question is whether the linear diffusion mechanism is defined by translation coupled with rotation, a mechanism that is often termed sliding.
View Article and Find Full Text PDFDNA mismatch repair (MMR) is an important postreplication process that eliminates mispaired or unpaired nucleotides to ensure genomic replication fidelity. In humans, Msh2-Msh6 and Msh2-Msh3 are the two mismatch repair initiation factors that recognize DNA lesions. While X-ray crystal structures exist for these proteins in complex with DNA lesions, little is known about their structures during the initial search along nonspecific double-stranded DNA, because they are short-lived and difficult to determine experimentally.
View Article and Find Full Text PDFPurpose Of Review: This review is to provide an update on the current understanding of rheumatoid arthritis (RA) development related to disease development prior to the onset clinically apparent synovitis (i.e. Pre-RA), and opportunities for disease prevention.
View Article and Find Full Text PDFLassa virus (LASV) is a notorious human pathogen in West Africa. Its class I trimeric spike complex displays a distinct architecture, and its cell entry mechanism involves unique attributes not shared by other related viruses. We determined the crystal structure of the GP2 fusion glycoprotein from the spike complex of LASV (GP2) in its post-fusion conformation.
View Article and Find Full Text PDFBackground: Acquired thrombophilia is a potential sequela of malignancy, chronic inflammation, and conditions characterized by severe protein deficiency (for example, nephrotic syndrome, protein-losing enteropathy). As such, venous thrombosis is often a feature, and occasionally a presenting sign, of systemic disease. Ménétrier's disease is a rare hyperplastic gastropathy that may lead to gastrointestinal protein loss and hypoalbuminemia.
View Article and Find Full Text PDFNucleic Acids Res
July 2018
Several DNA-binding proteins, such as topoisomerases, helicases and sliding clamps, have a toroidal (i.e. ring) shape that topologically traps DNA, with this quality being essential to their function.
View Article and Find Full Text PDFClin Pharmacol Drug Dev
March 2018
Clin Pharmacol Drug Dev
September 2016
J Clin Pharmacol
September 2016
Antipsychotic medications are widely used in the management of behavioral and psychological symptoms of dementia. While nonpharmacological interventions should be the first-line treatment for behavioral symptoms of dementia, these are often unfeasible and/or ineffective. Conventional and atypical antipsychotic agents appear to have modest to moderate clinical efficacy in the treatment of these symptoms, though it is unclear which individual agents are most effective.
View Article and Find Full Text PDFGlycosylation plays not only a functional role but can also modify the biophysical properties of the modified protein. Usually, natural glycosylation results in protein stabilization; however, in vitro and in silico studies showed that sometimes glycosylation results in thermodynamic destabilization. Here, we applied coarse-grained and all-atom molecular dynamics simulations to understand the mechanism underlying the loss of stability of the MM1 protein by glycosylation.
View Article and Find Full Text PDFClin Pharmacokinet
June 2015
Bariatric surgery constitutes an approach to the management of obesity in which the anatomy of the gastrointestinal tract is altered to reduce access of nutrients to absorptive surfaces, to restrict the absolute volume of material that can be ingested at once, or a combination of the two. Roux-en-Y gastric bypass (RYGB), currently the most common bariatric surgical procedure worldwide, has both malabsorptive and restrictive features. RYGB can be associated with alterations in absorption and disposition of medications.
View Article and Find Full Text PDFPEGylation of protein side chains has been used for more than 30 years to enhance the pharmacokinetic properties of protein drugs. However, there are no structure- or sequence-based guidelines for selecting sites that provide optimal PEG-based pharmacokinetic enhancement with minimal losses to biological activity. We hypothesize that globally optimal PEGylation sites are characterized by the ability of the PEG oligomer to increase protein conformational stability; however, the current understanding of how PEG influences the conformational stability of proteins is incomplete.
View Article and Find Full Text PDFJ Clin Pharmacol
December 2014
The azole antifungal agent ketoconazole has been available since 1981 for the treatment of fungal infections. In 2013, the American Food and Drug Administration and the European Medicines Agency issued warnings or prohibitions against the clinical use of oral ketoconazole due to the risk of liver injury which may lead to liver transplantation or death. From the available published evidence it is difficult to determine the actual incidence or prevalence of liver injury during clinical use of ketoconazole as an antifungal.
View Article and Find Full Text PDFActa Crystallogr Sect F Struct Biol Cryst Commun
March 2012
The use of whole insect larvae as a source of recombinant proteins offers a more cost-effective method of producing large quantities of human proteins than conventional cell-culture approaches. Human carboxylesterase 1 has been produced in and isolated from whole Trichoplusia ni larvae. The recombinant protein was crystallized and its structure was solved to 2.
View Article and Find Full Text PDFActa Crystallogr D Biol Crystallogr
January 2012
β-Secretase (β-site amyloid precursor protein-cleaving enzyme 1; BACE1) is a transmembrane aspartic protease that cleaves the β-amyloid precursor protein en route to generation of the amyloid β-peptide (Aβ) that is believed to be responsible for the Alzheimer's disease amyloid cascade. It is thus a prime target for the development of inhibitors which may serve as drugs in the treatment and/or prevention of Alzheimer's disease. In the following determination of the crystal structures of both apo and complexed BACE1, structural analysis of all crystal structures of BACE1 deposited in the PDB and molecular dynamics (MD) simulations of monomeric and `dimeric' BACE1 were used to study conformational changes in the active-site region of the enzyme.
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