Search results for "plasma protein"
showing 10 items of 193 documents
Low density lipoproteins and human serum albumin as the carriers of squalenoylated drugs: insights from molecular simulations
2018
We have studied the interaction of three clinically promising squalenoylated drugs (gemcitabine-squalene, adenine-squalene, and doxorubicin-squalene) with low-density lipoproteins (LDL) by means of atomistic molecular dynamics simulations. It is shown that all studied squalenoylated drugs accumulate inside the LDL particles. This effect is promoted by the squalene moiety, which acts as an anchor and drives the hydrophilic drugs into the hydrophobic core of the LDL lipid droplet. Our data suggest that LDL particles could be a universal carriers of squalenoylated drugs in the bloodstream. Interaction of gemcitabine-squalene with human serum albumin (HSA) was also studied by ensemble of dockin…
Characterization of the binding of benzodiazepines to human serum albumin
1973
The binding of eleven benzodiazepine derivatives to human serum albumin (HSA) was determined by means of sephadex gel filtration. The albumin binding of the substances was characterized by the percentage of bound drug, the binding constants k +, K 1 and m, the number of binding sites per albumin molecule, and the free binding energy. Under the conditions chosen in these experiments there seems to exist only one binding site of the same type for all investigated benzodiazepines at the HSA molecule. The affinities of the benzodiazepines to this binding site are very different. It is discussed which part of the benzodiazepine molecule represents the main binding group.
Antibodies directed to drug epitopes to investigate the structure of drug-protein photoadducts. Recognition of a common photobound substructure in ti…
2001
Drug-induced photoallergy is an immune adverse reaction to the combined effect of drugs and light. From the mechanistic point of view, it first involves covalent binding of drug to protein resulting in the formation of a photoantigen. Hence, determination of the structures of drug-protein photoadducts is of great relevance to understand the molecular basis of photoallergy and cross-immunoreactivity among drugs. Looking for new strategies to investigate the covalent photobinding of drugs to proteins, we generated highly specific antibodies to drug chemical substructures. The availability of such antibodies has allowed us to discriminate between the different modes by which tiaprofenic acid (…
The Sensor Kinase DctS Forms a Tripartite Sensor Unit with DctB and DctA for Sensing C4-Dicarboxylates in Bacillus subtilis
2013
The DctSR two-component system of Bacillus subtilis controls the expression of the aerobic C4-dicarboxylate transporter DctA. Deletion of DctA leads to an increased dctA expression. The inactivation of DctB, an extracellular binding protein, is known to inhibit the expression of dctA. Here, interaction between the sensor kinase DctS and the transporter DctA as well as the binding protein DctB was demonstrated in vivo using streptavidin (Strep) or His protein interaction experiments (mSPINE or mHPINE), and the data suggest that DctA and DctB act as cosensors for DctS. The interaction between DctS and DctB was also confirmed by the bacterial two-hybrid system (BACTH). In contrast, no indicati…
Surface-exposed Amino Acid Residues of HPV16 L1 Protein Mediating Interaction with Cell Surface Heparan Sulfate
2007
Efficient infection of cells by human papillomaviruses (HPVs) and pseudovirions requires primary interaction with cell surface proteoglycans with apparent preference for species carrying heparan sulfate (HS) side chains. To identify residues contributing to virus/cell interaction, we performed point mutational analysis of the HPV16 major capsid protein, L1, targeting surface-exposed amino acid residues. Replacement of lysine residues 278, 356, or 361 for alanine reduced cell binding and infectivity of pseudovirions. Various combinations of these amino acid exchanges further decreased cell attachment and infectivity with residual infectivity of less than 5% for the triple mutant, suggesting …
Binding of PTEN to specific PDZ domains contributes to PTEN protein stability and phosphorylation by microtubule-associated serine/threonine kinases
2005
The tumor suppressor phosphatase PTEN is a key regulator of cell growth and apoptosis that interacts with PDZ domains from regulatory proteins, including MAGI-1/2/3, hDlg, and MAST205. Here we identified novel PTEN-binding PDZ domains within the MAST205-related proteins, syntrophin-associated serine/threonine kinase and MAST3, characterized the regions of PTEN involved in its interaction with distinctive PDZ domains, and analyzed the functional consequences on PTEN of PDZ domain binding. Using a panel of PTEN mutations, as well as PTEN chimeras containing distinct domains of the related protein TPTE, we found that the PTP and C2 domains of PTEN do not affect PDZ domain binding and that the …
Determination of 14-3-3 protein levels in cerebrospinal fluid from Creutzfeldt-Jakob patients by a highly sensitive capture assay.
2001
The level of 14-3-3gamma protein was determined in the cerebrospinal fluid (CSF) from patients with Creutzfeldt-Jakob disease (CJD) and non-CJD patients applying a new and fast microplate assay (14-3-3 protein capture assay), based on the binding to a peptide comprising a phosphorylated recognition motif of 14-3-3 protein. The levels of the gamma-isoform of 14-3-3 protein in CSF samples from CJD patients (n=41) were significantly higher than those observed in patients with non-CJD dementias (n=36) suggesting that this capture assay is a reliable method in the diagnosis of CJD. Since this assay allows the direct measurement of 14-3-3 protein in the CSF without prior concentration it is an ea…
Glyceraldehyde-3-phosphate dehydrogenase regulates endothelin-1 expression by a novel, redox-sensitive mechanism involving mRNA stability
2008
17 pages.-- PMID: 18809573 [PubMed].-- Printed version published on Dec 2008.
Drug Binding Properties of Tyrosine-Modified Human Serum Albumin
1978
Human serum albumin (HSA) has only a small number of specific binding sites for drugs. There are facts indicating that tyrosine residues may be involved in these binding sites. Thus we modified HSA with tetranitromethan, a reagent specific for tyrosine residues in proteins. As derived from an UV-absorption quotient three albumins with a degree of modification of two, five and eight residues per molecule were obtained. Only for the albumin with eight residues modified a small reduction of ordered secondary structure was found.
Nautilin-63, a novel acidic glycoprotein from the shell nacre of Nautilus macromphalus
2011
In molluscs, and more generally in metazoan organisms, the production of a calcified skeleton is a complex molecular process that is regulated by the secretion of an extracellular organic matrix. This matrix constitutes a cohesive and functional macromolecular assemblage, containing mainly proteins, glycoproteins and polysaccharides that, together, control the biomineral formation. These macromolecules interact with the extruded precursor mineral ions, mainly calcium and bicarbonate, to form complex organo-mineral composites of well-defined microstructures. For several reasons related to its remarkable mechanical properties and to its high value in jewelry, nacre is by far the most studied …