The thermodynamic interaction between a substance and WATER.
A separation technique which combines LIQUID CHROMATOGRAPHY and CAPILLARY ELECTROPHORESIS.
Chromatographic techniques in which the mobile phase is a liquid.
The systematic study of the structure and function of the complete set of glycans (the glycome) produced in a single organism and identification of all the genes that encode glycoproteins.
A chromatography technique in which the stationary phase is composed of a non-polar substance with a polar mobile phase, in contrast to normal-phase chromatography in which the stationary phase is a polar substance with a non-polar mobile phase.
Compounds in which a methyl group is attached to the cyano moiety.
Heparin derivatives. The term has also been used more loosely to include naturally occurring and synthetic highly-sulphated polysaccharides of similar structure. Heparinoid preparations have been used for a wide range of applications including as anticoagulants and anti-inflammatories and they have been claimed to have hypolipidemic properties. (From Martindale, The Extra Pharmacopoeia, 30th, p232)
A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
Polysaccharides are complex carbohydrates consisting of long, often branched chains of repeating monosaccharide units joined together by glycosidic bonds, which serve as energy storage molecules (e.g., glycogen), structural components (e.g., cellulose), and molecular recognition sites in various biological systems.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.
The systematic study of the complete complement of proteins (PROTEOME) of organisms.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

Allosteric activation mechanism of the alpha 1 beta 2 gamma 2 gamma-aminobutyric acid type A receptor revealed by mutation of the conserved M2 leucine. (1/4501)

A conserved leucine residue in the midpoint of the second transmembrane domain (M2) of the ligand-activated ion channel family has been proposed to play an important role in receptor activation. In this study, we assessed the importance of this leucine in the activation of rat alpha 1 beta 2 gamma 2 GABA receptors expressed in Xenopus laevis oocytes by site-directed mutagenesis and two-electrode voltage clamp. The hydrophobic conserved M2 leucines in alpha1(L263), beta2(L259), and gamma 2(L274) subunits were mutated to the hydrophilic amino acid residue serine and coexpressed in all possible combinations with their wild-type and/or mutant counterparts. The mutation in any one subunit decreased the EC(50) and created spontaneous openings that were blocked by picrotoxin and, surprisingly, by the competitive antagonist bicuculline. The magnitudes of the shifts in GABA EC(50) and picrotoxin IC(50) as well as the degree of spontaneous openings were all correlated with the number of subunits carrying the leucine mutation. Simultaneous mutation of the GABA binding site (beta 2Y157S; increased the EC(50)) and the conserved M2 leucine (beta 2L259S; decreased the EC(50)) produced receptors with the predicted intermediate agonist sensitivity, indicating the two mutations affect binding and gating independently. The results are discussed in light of a proposed allosteric activation mechanism.  (+info)

Gamma-aminobutyric acid increases the water accessibility of M3 membrane-spanning segment residues in gamma-aminobutyric acid type A receptors. (2/4501)

Gamma-aminobutyric acid type A (GABA(A)) receptors are members of the ligand-gated ion channel gene superfamily. Using the substituted cysteine accessibility method, we investigated whether residues in the alpha(1)M3 membrane-spanning segment are water-accessible. Cysteine was substituted, one at a time, for each M3 residue from alpha(1)Ala(291) to alpha(1)Val(307). The ability of these mutants to react with the water-soluble, sulfhydryl-specific reagent pCMBS(-) was assayed electrophysiologically. Cysteines substituted for alpha(1)Ala(291) and alpha(1)Tyr(294) reacted with pCMBS(-) applied both in the presence and in the absence of GABA. Cysteines substituted for alpha(1)Phe(298), alpha(1)Ala(300), alpha(1)Leu(301), and alpha(1)Glu(303) only reacted with pCMBS(-) applied in the presence of GABA. We infer that the pCMBS(-) reactive residues are on the water-accessible surface of the protein and that GABA induces a conformational change that increases the water accessibility of the four M3 residues, possibly by inducing the formation of water-filled crevices that extend into the interior of the protein. Others have shown that mutations of alpha(1)Ala(291), a water-accessible residue, alter volatile anesthetic and ethanol potentiation of GABA-induced currents. Water-filled crevices penetrating into the interior of the membrane-spanning domain may allow anesthetics and alcohol to reach their binding sites and thus may have implications for the mechanisms of action of these agents.  (+info)

A numerical measure of amino acid residues similarity based on the analysis of their surroundings in natural protein sequences. (3/4501)

A measure of similarity between amino acid residues based on the analysis of the surroundings of each residue in primary structures of native proteins is proposed. The statistical data used for this purpose were obtained from the analysis of 168,808 protein sequences, which comprise the Protein Identification Research database (release 63). Using various threshold values of the proposed measure, amino acid residues were classified into several groups. The classification elaborated differs essentially from groupings previously used. The numerical measure of amino acid residues similarity can be used in site-directed mutagenesis studies for the prediction of probability of local spatial rearrangements in proteins.  (+info)

Sterically stabilized cationic liposomes improve the uptake and immunostimulatory activity of CpG oligonucleotides. (4/4501)

Immunostimulatory CpG oligonucleotides (ODN) show promise as immune adjuvants, anti-allergens, and immunoprotective agents. Increasing the bioavailability and duration of action of CpG ODN should improve their therapeutic utility. Encapsulating ODN in sterically stabilized cationic liposomes provides protection from serum nucleases while facilitating uptake by B cells, dendritic cells, and macrophages. In a pathogen challenge model, sterically stabilized cationic liposomes encapsulation doubled the duration of CpG ODN-induced immune protection. In an immunization model, coencapsulation of CpG ODN with protein Ag (OVA) magnified the resultant Ag-specific IFN-gamma and IgG responses by 15- to 40-fold compared with Ag plus CpG ODN alone. These findings support the use of sterically stabilized cationic liposomes to significantly enhance the therapeutic efficacy of CpG ODN.  (+info)

Role of interfacial hydrophobic residues in the stabilization of the leucine zipper structures of the transcription factors c-Fos and c-Jun. (5/4501)

This study documents a new and versatile experimental approach to study the relative stabilization energetics of recombinant polypeptide and protein mutants. In particular, the effect of temperature change over the range of T = 278-338 K on the thermodynamics of interaction of several leucine zipper coiled-coil polypeptides related to the transcription factors, c-Fos and c-Jun, following binding to immobilized n-octyl ligands has been determined. Plots of the change in heat capacity, DeltaC(p)0, versus T, in combination with the corresponding van't Hoff plots, allow the energetics of the interaction of polypeptides with n-octyl ligands to be rationalized and the respective mid-point transition temperatures, T(m) values, determined for the melting of their supramolecular structures. The derived experimental data correlated well with information available from other procedures, confirming that this new approach provides complementary insight into the interaction thermodynamics and the molecular nature of the thermal stability of recombinant polypeptides in non-polar or other types of chemical environments.  (+info)

Bile-salt hydrophobicity is a key factor regulating rat liver plasma-membrane communication: relation to bilayer structure, fluidity and transporter expression and function. (6/4501)

Bile-salt hydrophobicity regulates biliary phospholipid secretion and subselection. The aim of this study was to determine whether bile salts can influence liver plasma membrane phospholipids and fluidity in relation to the ATP-dependent transporter. Rats were depleted of bile salts by overnight biliary diversion and then sodium taurocholate was infused intravenously at a constant rate (200 nmol/min per 100 g of body weight), followed by infusion of bile salts with various hydrophobicities (taurochenodeoxycholate, tauroursodeoxycholate, tauro-beta-muricholate, tauro-alpha-muricholate at 200 nmol/min per 100 g of body weight). The hydrophobicity of the infused bile salts correlated with that of biliary phospholipids, but was inversely related to that of the canalicular membrane bilayer. Canalicular membrane fluidity (estimated by 1,6-diphenyl-1,3,5-hexatriene fluorescence depolarization) and expression of multidrug-resistance proteins (Mrp2, Mrp3) and apical Na(+)-dependent bile-salt transporter (ASBT) were increased by hydrophilic bile salts, although there was no marked change in the expression of P-glycoprotein subfamilies (Mdr2). Bile-salt export pump (Bsep) expression was increased along with increasing bile-salt hydrophobicity. Bile salts modulate canalicular membrane phospholipids and membrane fluidity, as well as the ATP-dependent transporter expression and function, and these actions are associated with their hydrophobicity. The cytoprotective effect of hydrophilic bile salts seems to be associated with induction of Mrp2, Mrp3 and ASBT.  (+info)

Structure-function analysis of the heat shock factor-binding protein reveals a protein composed solely of a highly conserved and dynamic coiled-coil trimerization domain. (7/4501)

Heat shock factor-binding protein (HSBP) 1 is a small, evolutionarily conserved protein originally identified in a yeast two-hybrid screen using the trimerization domain of heat shock factor (HSF) 1 as the bait. Similar in size to HSF1 trimerization domain, human HSBP1 contains two arrays of hydrophobic heptad repeats (designated HR-N and HR-C) characteristic of coiled-coil proteins. Proteins of the HSBP family are relatively small (<100 residues), comprising solely a putative coiled-coil oligomerization domain without any other readily recognizable structural or functional motif. Our biophysical and biochemical characterization of human HSBP1 reveals a cooperatively folded protein with high alpha-helical content and moderate stability. NMR analyses reveal a single continuous helix encompassing both HR-N and HR-C in the highly conserved central region, whereas the less conserved carboxyl terminus is unstructured and accessible to proteases. Unlike previously characterized coiled-coils, backbone 15N relaxation measurements implicate motional processes on the millisecond time scale in the coiled-coil region. Analytical ultracentrifugation and native PAGE studies indicate that HSBP1 is predominantly trimeric over a wide concentration range. NMR analyses suggest a rotationally symmetric trimer. Because the highly conserved hydrophobic heptad repeats extend over 60% of HSBP1, we propose that HSBP most likely regulates the function of other proteins through coiled-coil interactions.  (+info)

Optimization of microbial specificity in cyclic peptides by modulation of hydrophobicity within a defined structural framework. (8/4501)

In the present study we have utilized the structural framework of the analog GS14K4 (cyclo(VKLd-KVd-YPL KVKLd-YP, where d denotes a d-amino acid)), to examine the role of hydrophobicity in microbial activity and specificity. The hydrophobicity of GS14K4 was systematically altered by residue replacements in the hydrophobic sites of the molecule to produce a series of analogs that were either less or more hydrophobic than the parent compound. Circular dichroism spectroscopy and reversed-phase high performance liquid chromatography analysis showed that the molecules were structurally similar and only differed in overall hydrophobicity. The hydrophobicity of GS14K4 was found to be the midpoint for hemolytic activity, with more hydrophobic analogs exhibiting increased hemolytic activity and less hydrophobic analogs showing decreased hemolytic activity. For antimicrobial activity there were differences between the hydrophobicity requirements against Gram-positive and Gram-negative microorganisms. The hydrophobicity of GS14K4 was sufficient for maximum activity against Gram-negative microorganisms and yeast, with no further increases in activity occurring with increasing hydrophobicity. With Gram-positive microorganisms significant increases in activity with increasing hydrophobicity were seen in three of the six microorganisms tested. A therapeutic index (calculated as a measure of specificity of the peptides for the microorganisms over human erythrocytes) served to define the boundaries of a therapeutic window within which lay the optimum peptide hydrophobicity for each microorganism. The therapeutic window was found to be at a lower hydrophobicity level for Gram-negative microorganisms than for Gram-positive microorganisms, although the limits were more variable for the latter. Our results show that the balance between activity and specificity in the present cyclic peptides can be optimized for each microorganism by systematic modulation of hydrophobicity.  (+info)

Hydrophobic interactions: These are the interactions that occur between non-polar molecules or groups of atoms in an aqueous environment, leading to their association or aggregation. The term "hydrophobic" means "water-fearing" and describes the tendency of non-polar substances to repel water. When non-polar molecules or groups are placed in water, they tend to clump together to minimize contact with the polar water molecules. These interactions are primarily driven by the entropy increase of the system as a whole, rather than energy minimization. Hydrophobic interactions play crucial roles in various biological processes, such as protein folding, membrane formation, and molecular self-assembly.

Hydrophilic interactions: These are the interactions that occur between polar molecules or groups of atoms and water molecules. The term "hydrophilic" means "water-loving" and describes the attraction of polar substances to water. When polar molecules or groups are placed in water, they can form hydrogen bonds with the surrounding water molecules, which helps solvate them. Hydrophilic interactions contribute to the stability and functionality of various biological systems, such as protein structure, ion transport across membranes, and enzyme catalysis.

Capillary electrochromatography (CEC) is a separation technique that combines the principles of capillary electrophoresis and high-performance liquid chromatography (HPLC). In CEC, an electric field is applied to a liquid flowing through a narrow fused-silica capillary tube packed with a stationary phase.

The analytes (the substances being separated) are carried by the electroosmotic flow of the liquid and interact with the stationary phase as they migrate through the capillary, resulting in separation based on both charge and size/hydrophobicity. CEC offers high efficiency, resolution, and sensitivity for the separation of a wide range of analytes, including small molecules, peptides, proteins, and nucleic acids.

The medical definition of Capillary Electrochromatography is not commonly used as it is primarily employed in research settings for the analysis of various biological samples, pharmaceuticals, and environmental pollutants.

Liquid chromatography (LC) is a type of chromatography technique used to separate, identify, and quantify the components in a mixture. In this method, the sample mixture is dissolved in a liquid solvent (the mobile phase) and then passed through a stationary phase, which can be a solid or a liquid that is held in place by a solid support.

The components of the mixture interact differently with the stationary phase and the mobile phase, causing them to separate as they move through the system. The separated components are then detected and measured using various detection techniques, such as ultraviolet (UV) absorbance or mass spectrometry.

Liquid chromatography is widely used in many areas of science and medicine, including drug development, environmental analysis, food safety testing, and clinical diagnostics. It can be used to separate and analyze a wide range of compounds, from small molecules like drugs and metabolites to large biomolecules like proteins and nucleic acids.

Glycomics is the study of the glycome, which refers to the complete set of carbohydrates or sugars (glycans) found on the surface of cells and in various biological fluids. Glycomics encompasses the identification, characterization, and functional analysis of these complex carbohydrate structures and their interactions with other molecules, such as proteins and lipids.

Glycans play crucial roles in many biological processes, including cell-cell recognition, signaling, immune response, development, and disease progression. The study of glycomics has implications for understanding the molecular basis of diseases like cancer, diabetes, and infectious disorders, as well as for developing novel diagnostic tools and therapeutic strategies.

Reverse-phase chromatography is a type of liquid chromatography that is commonly used in analytical chemistry and biochemistry to separate, identify, and purify complex mixtures of chemicals or biological molecules. In this technique, the stationary phase is a nonpolar solid, such as octadecyl silica (ODS) or C18, which is coated with a polar solvent, while the mobile phase is a nonpolar solvent, such as methanol or acetonitrile.

The term "reverse-phase" refers to the fact that the polarity of the stationary and mobile phases is reversed compared to normal-phase chromatography. In normal-phase chromatography, the stationary phase is polar and the mobile phase is nonpolar, which results in the separation of analytes based on their polarity. However, in reverse-phase chromatography, the stationary phase is nonpolar and the mobile phase is polar, which means that the separation of analytes is based on their hydrophobicity or hydrophilicity.

In reverse-phase chromatography, hydrophobic molecules elute more slowly than hydrophilic molecules because they have a stronger affinity for the nonpolar stationary phase. The retention time of an analyte can be adjusted by changing the composition of the mobile phase or the pH of the solution. This technique is widely used in the analysis of drugs, metabolites, peptides, proteins, and other biological molecules.

Acetonitrile is an organic compound with the formula CH3CN. It is a colorless liquid that is used as a solvent and in the production of various chemicals. Acetonitrile is weakly basic and polar, and it has a unique smell that is often described as unpleasant or sweet.

Acetonitrile is not considered to be a medication or a drug, so it does not have a medical definition. However, it is sometimes used in the medical field as a solvent for various applications, such as in the preparation of pharmaceutical products or in laboratory research. It is important to handle acetonitrile with care, as it can be harmful if swallowed, inhaled, or contacted with the skin.

Heparinoids are a group of substances that have similar properties to heparin, a highly sulfated glycosaminoglycan found in mast cells and basophils. Heparin is a powerful anticoagulant that works by accelerating the action of an enzyme called antithrombin III, which inhibits the formation of blood clots.

Heparinoids are often used as alternative anticoagulants to heparin in clinical settings. They have similar mechanisms of action and can also inhibit the coagulation cascade, preventing the formation of blood clots. However, heparinoids have a lower anticoagulant activity than heparin and may have different side effect profiles.

Examples of heparinoids include low molecular weight heparins (LMWHs), fondaparinux, and danaparoid. LMWHs are derived from standard heparin by chemical or enzymatic depolymerization and have a lower molecular weight than heparin. They have a more predictable anticoagulant response and longer half-life than standard heparin, making them useful for outpatient treatment of deep vein thrombosis and pulmonary embolism.

Fondaparinux is a synthetic pentasaccharide that selectively binds to antithrombin III and enhances its inhibitory activity against factor Xa, a key enzyme in the coagulation cascade. It has a long half-life and predictable pharmacokinetics, making it useful for the prevention and treatment of venous thromboembolism.

Danaparoid is a mixture of heparan sulfate, dermatan sulfate, and chondroitin sulfate derived from pig intestinal mucosa. It has a lower anticoagulant activity than heparin but a longer half-life and less frequent dosing requirements. Danaparoid is used for the prevention and treatment of venous thromboembolism, as well as for the management of heparin-induced thrombocytopenia (HIT), a rare but serious complication of heparin therapy.

Tandem mass spectrometry (MS/MS) is a technique used to identify and quantify specific molecules, such as proteins or metabolites, within complex mixtures. This method uses two or more sequential mass analyzers to first separate ions based on their mass-to-charge ratio and then further fragment the selected ions into smaller pieces for additional analysis. The fragmentation patterns generated in MS/MS experiments can be used to determine the structure and identity of the original molecule, making it a powerful tool in various fields such as proteomics, metabolomics, and forensic science.

"Wettability" is not a term that has a specific medical definition. It is a term that is more commonly used in the fields of chemistry, physics, and materials science to describe how well a liquid spreads on a solid surface. In other words, it refers to the ability of a liquid to maintain contact with a solid surface, which can have implications for various medical applications such as the design of medical devices or the study of biological surfaces. However, it is not a term that would typically be used in a clinical medical context.

Mass spectrometry with electrospray ionization (ESI-MS) is an analytical technique used to identify and quantify chemical species in a sample based on the mass-to-charge ratio of charged particles. In ESI-MS, analytes are ionized through the use of an electrospray, where a liquid sample is introduced through a metal capillary needle at high voltage, creating an aerosol of charged droplets. As the solvent evaporates, the analyte molecules become charged and can be directed into a mass spectrometer for analysis.

ESI-MS is particularly useful for the analysis of large biomolecules such as proteins, peptides, and nucleic acids, due to its ability to gently ionize these species without fragmentation. The technique provides information about the molecular weight and charge state of the analytes, which can be used to infer their identity and structure. Additionally, ESI-MS can be interfaced with separation techniques such as liquid chromatography (LC) for further purification and characterization of complex samples.

Polysaccharides are complex carbohydrates consisting of long chains of monosaccharide units (simple sugars) bonded together by glycosidic linkages. They can be classified based on the type of monosaccharides and the nature of the bonds that connect them.

Polysaccharides have various functions in living organisms. For example, starch and glycogen serve as energy storage molecules in plants and animals, respectively. Cellulose provides structural support in plants, while chitin is a key component of fungal cell walls and arthropod exoskeletons.

Some polysaccharides also have important roles in the human body, such as being part of the extracellular matrix (e.g., hyaluronic acid) or acting as blood group antigens (e.g., ABO blood group substances).

Mass spectrometry (MS) is an analytical technique used to identify and quantify the chemical components of a mixture or compound. It works by ionizing the sample, generating charged molecules or fragments, and then measuring their mass-to-charge ratio in a vacuum. The resulting mass spectrum provides information about the molecular weight and structure of the analytes, allowing for identification and characterization.

In simpler terms, mass spectrometry is a method used to determine what chemicals are present in a sample and in what quantities, by converting the chemicals into ions, measuring their masses, and generating a spectrum that shows the relative abundances of each ion type.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

Chromatography is a technique used in analytical chemistry for the separation, identification, and quantification of the components of a mixture. It is based on the differential distribution of the components of a mixture between a stationary phase and a mobile phase. The stationary phase can be a solid or liquid, while the mobile phase is a gas, liquid, or supercritical fluid that moves through the stationary phase carrying the sample components.

The interaction between the sample components and the stationary and mobile phases determines how quickly each component will move through the system. Components that interact more strongly with the stationary phase will move more slowly than those that interact more strongly with the mobile phase. This difference in migration rates allows for the separation of the components, which can then be detected and quantified.

There are many different types of chromatography, including paper chromatography, thin-layer chromatography (TLC), gas chromatography (GC), liquid chromatography (LC), and high-performance liquid chromatography (HPLC). Each type has its own strengths and weaknesses, and is best suited for specific applications.

In summary, chromatography is a powerful analytical technique used to separate, identify, and quantify the components of a mixture based on their differential distribution between a stationary phase and a mobile phase.

Reproducibility of results in a medical context refers to the ability to obtain consistent and comparable findings when a particular experiment or study is repeated, either by the same researcher or by different researchers, following the same experimental protocol. It is an essential principle in scientific research that helps to ensure the validity and reliability of research findings.

In medical research, reproducibility of results is crucial for establishing the effectiveness and safety of new treatments, interventions, or diagnostic tools. It involves conducting well-designed studies with adequate sample sizes, appropriate statistical analyses, and transparent reporting of methods and findings to allow other researchers to replicate the study and confirm or refute the results.

The lack of reproducibility in medical research has become a significant concern in recent years, as several high-profile studies have failed to produce consistent findings when replicated by other researchers. This has led to increased scrutiny of research practices and a call for greater transparency, rigor, and standardization in the conduct and reporting of medical research.

Glycosylation is the enzymatic process of adding a sugar group, or glycan, to a protein, lipid, or other organic molecule. This post-translational modification plays a crucial role in modulating various biological functions, such as protein stability, trafficking, and ligand binding. The structure and composition of the attached glycans can significantly influence the functional properties of the modified molecule, contributing to cell-cell recognition, signal transduction, and immune response regulation. Abnormal glycosylation patterns have been implicated in several disease states, including cancer, diabetes, and neurodegenerative disorders.

Proteomics is the large-scale study and analysis of proteins, including their structures, functions, interactions, modifications, and abundance, in a given cell, tissue, or organism. It involves the identification and quantification of all expressed proteins in a biological sample, as well as the characterization of post-translational modifications, protein-protein interactions, and functional pathways. Proteomics can provide valuable insights into various biological processes, diseases, and drug responses, and has applications in basic research, biomedicine, and clinical diagnostics. The field combines various techniques from molecular biology, chemistry, physics, and bioinformatics to study proteins at a systems level.

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

The aggregates are hydrophobic and hydrophilic dimers, joined by intermolecular interaction. Bridging of the hydrophilic dimer ... August 2003). "Interaction of Viscotoxins A3 and B with Membrane Model Systems: Implications to Their Mechanism of Action". ... Since both of these amino acids are also hydrophobic this mutation is thought to have little interference with the folding and ... This relationship will indicate an interaction between Ca2+ and the toxin molecule at the membrane level. The Ca2+ dependence ...
The phospholipid molecule is amphipathic; it contains a hydrophilic polar head and a hydrophobic nonpolar tail. The ... These latter interactions drive the bilayer structure that acts as a barrier for ions and molecules. There are various types of ... This interaction is possible thanks to the ribosome, which serves as the site for protein synthesis. The ribosome possesses ... 2001). Lipid bilayers : structure and interactions ; with 6 tables. Berlin [u.a.]: Springer. ISBN 978-3540675556. Stryer, ...
As O-GlcNAc is highly hydrophilic, its presence may disrupt hydrophobic protein-protein interactions. For example, O-GlcNAc ... It has been suggested that O-GlcNAc plays a role in the interaction of α-catenin and β-catenin. Co-translational O-GlcNAc has ... This interaction is associated with H2B S112 O-GlcNAc, which in turn is associated with H2B K120 monoubiquitination. ... Mutagenesis to tryptophan has been used to mimic the steric bulk of O-GlcNAc, though tryptophan is much more hydrophobic than O ...
Thus, the exterior of a protein is typically hydrophilic, whereas the interior is typically hydrophobic. Protein structures are ... The non-covalent interactions include ionic interactions and weak van der Waals interactions. Ionic interactions form between ... Van der Waals interactions include nonpolar interactions (i.e. London dispersion force) and polar interactions (i.e. hydrogen ... This folding process is driven by the hydrophobic effect: a tendency for hydrophobic (water-fearing) portions of the protein to ...
... exterior heads and a hydrophobic interior where proteins can interact with hydrophilic heads through polar interactions, but ... Hydrophobic interactions (also known as the hydrophobic effect) are the major driving forces in the formation of lipid bilayers ... An increase in interactions between hydrophobic molecules (causing clustering of hydrophobic regions) allows water molecules to ... The arrangement of hydrophilic heads and hydrophobic tails of the lipid bilayer prevent polar solutes (ex. amino acids, nucleic ...
Similarly, since the heads are hydrophilic, the head-water interaction is more favourable than head-air interaction. The ... Langmuir-Blodgett films are inherently 2D-structures and can be built up layer by layer, by dipping hydrophobic or hydrophilic ... Surfactants (or surface-acting agents) are molecules with hydrophobic 'tails' and hydrophilic 'heads'. When surfactant ... with a hydrophilic head and a hydrophobic tail (example: fatty acids) or nowadays commonly of nanoparticles. Langmuir-Blodgett ...
The outer surface of the protein is hydrophilic, allowing the complex to be soluble. The use of hydrophobic interactions, with ... The structure forms an internal hydrophobic cavity in which 1-2 lipids can be bound. ... very few charged interactions, allows the protein to have broad specificity for a range of lipids. PLTPs are pan-allergens, and ...
The plasma membranes of cells contain phospholipids composed of a hydrophilic phosphate head and two hydrophobic fatty acid ... are characterized by their interactions. The interactions between these two fatty acids directly affect the signaling pathways ...
Since the new interactions between the hydrophilic amino acids are stronger than hydrophobic-hydrophilic interactions, this is ... In a hydrophobic environment, the hydrophilic amino acids will concentrate at the core of the protein, while the hydrophobic ... In a hydrophilic environment such as cytosol, the hydrophobic amino acids will concentrate at the core of the protein, while ... Hydrogen bonds and hydrophobic interactions are important stabilizing forces in proteins. If the temperature rises and ...
Additionally, the hydrophilic/hydrophobic interactions of the micelles are similar to that in the polar regions of a membrane. ... Micelles are composed of surfactant, or detergent, monomers with a hydrophobic moiety, or tail, on one end, and a hydrophilic ... Hydrophilic drugs are often unretained using conventional HPLC, are retained by MLC due to solubilization into the micelles. ... Too high a concentration of the organic may cause the micelle to disperse, as it relies on hydrophobic effects for its ...
... utilized to be conjugated with hydrophilic polymer chains to generate higher ordered structure through hydrophobic interactions ... At the critical aggregation concentration, they form nanoparticles due to the hydrophobic interactions. The resulting ... Metal-binding interactions, host-guest, and boronic acid-based chemistries are widely studied as non-covalent conjugation ... For example, conjugation of a single chain of the hydrophilic polyethylene glycol (PEG) can increase the hydrodynamic radius of ...
These hydrophilic and hydrophobic interactions can cause the destabilization of these systems, which lead to conformational ... These systems are governed by hydrophilic and hydrophobic interactions of self-assembled drug carriers within a certain pH ... These changes can include conformational changes and surface interactions that can lead to the degradation or swelling/ ...
This bond may consist of an induced dipole interaction between a hydrophobic matrix and a hydrophobic anchor. As long as the ... reaction medium is hydrophilic (polar) in nature the anchor will remain on the solid phase. Switching to a nonpolar solvent ... In one experimental setup the hydrophobic matrix is RP silica gel (C18) and the anchor is acridone. Acridone is N-alkylated and ... synthesis whereby the organic substrate is bonded to the solid phase not by a covalent bond but by other chemical interactions ...
Physically cross-linked hydrogel dressings are assembled via ionic interaction, hydrogen bonding, hydrophobic interactions, or ... The insoluble hydrophilic structures absorb polar wound exudates and allow oxygen diffusion at the wound bed to accelerate ... Self-assembly via hydrophobic interactions can be induced in amphiphilic polysaccharides-based gels by addition of water; it ... Covalent interactions involved in self-healing include Schiff base formation and disulfide exchange. Non-covalent interactions ...
Hydrophobic interactions rely heavily on physical crosslinking to form nanogels. In this method, hydrophobic groups are added ... Gota, Chie; Okabe, Kohki; Funatsu, Takashi; Harada, Yoshie; Uchiyama, Seiichi (2009). "Hydrophilic Fluorescent Nanogel ... Electrostatic interactions can form nanogels through the combination of anionic and cationic polymers in an aqueous solution. ... Ionotropic gelation can also leverage electrostatic interactions between multivalent anions and cations to form nanogels. ...
... a hydrophobic membrane anchor ("M"). The B repeats (36kD) were found to be responsible for the interaction with Ig light chains ... a hydrophilic, proline-rich putative cell wall-spanning region ("W") after the C repeats; ... Since no part of the heavy chain is involved in the binding interaction, Protein L binds a wider range of antibody classes than ... Protein L binds antibodies through light chain interactions. ... was found to bind immunoglobulins through L chain interaction, ...
In this case, the hydrophilic groups are sequestered in the micelle core and the hydrophobic groups extend away from the center ... since hydrophilic sequestration would create highly unfavorable electrostatic interactions. It is well established that for ... Moreover, thanks to the larger hydrophilic and hydrophobic parts, block copolymers can have a much more pronounced amphiphilic ... In water, the hydrophilic "heads" of surfactant molecules are always in contact with the solvent, regardless of whether the ...
Electrostatic interaction is the primary initial interaction when the pH is lower, while the chelating and hydrophobic effects ... which is composed of hydrophilic heads and a hydrophobic tail. The hydrophilic heads form the inner and outer linings of the ... The secondary interaction, the hydrophobic effect, involves the accumulation of nonpolar compounds away from water. Nonpolar ... The chelating and hydrophobic effects are common secondary interactions of antimicrobial polymers with microbes. Cationically ...
For instance, the Kyte-Doolittle scale indicates hydrophobic amino acids, whereas the Hopp-Woods scale measures hydrophilic ... There are a number of methods to measure the degree of interaction of polar solvents such as water with specific amino acids. ... which is composed of hydrophobic fatty acids. On the converse, amino acids with high hydrophilicity indicate that these ...
... aqueous solutions and hydrophobic-hydrophilic interactions. He is mainly concerned with theoretical and experimental aspects of ... 1974, ISBN 030630774X (out of print). Hydrophobic Interactions. 1980, ISBN 978-0-306-40222-7. Molecular Theory of Solutions. ...
... basic hydrolytic conditions typically produce a periodic structure because of hydrophobic and hydrophilic interactions between ... The hydrophobic nature of the PMO walls allow for better control in drug release. In this respect, it is not just the ... The theory was that the π-π interaction between the aromatic analytes and the phenylene bridge of the PMO framework leads to ... interactions among solvent evaporation, micelle formation/packing and sol condensation". RSC Advances. 1 (3): 401-407. Bibcode: ...
These long hydrophobic tails are able to aggregate together like this due to strong hydrophobic interactions and the end result ... Mature pilins and pseudopilins have a lollipop shaped structure, made up of a long hydrophobic tail and a globular hydrophilic ... In this reaction the hydrophobic tails of different pseudopilins mesh together leaving their globular hydrophilic heads exposed ... This interaction helps gate the type II secretion system and only when this gate is open are secretory proteins able to enter ...
In more hydrophobic surfaces, surfactants may form a bilayer on the solid, causing it to become more hydrophilic. The dynamic ... As wetting interactions are of great importance in various applications, it is often desired to predict and compare the wetting ... For water, a wettable surface may also be termed hydrophilic and a nonwettable surface hydrophobic. Superhydrophobic surfaces ... Generally, the rougher the surface, the more hydrophobic it is. If a drop is placed on a smooth, horizontal surface, it is ...
... hydrophilic, or hydrophobic residues. Upon binding, the receptor often undergoes a conformational change and may bind further, ... This interaction causes the exchange of GDP for GTP, which triggers structural changes within the alpha subunit of the G ... This interaction allows the hormone receptor to produce second messengers within the cell to aid response. Second messengers ... The changes interrupts the interaction of the alpha subunit with the beta-gamma complex and which results in a single alpha ...
... hydrophobic interactions, hydrophilic interactions, van der Waals force etc. When two or more polypeptide chains (either of ... Another biological role is energy storage (e.g., triglycerides). Most lipids consist of a polar or hydrophilic head (typically ... For lipids present in biological membranes, the hydrophilic head is from one of three classes: Glycolipids, whose heads contain ... apparently because of both positive and negative interactions of the extra OH on the ribose. Structured RNA molecules can do ...
The stronger interactions between the hydrophilic AFM tip and the hydrophilic side of the Janus nanoparticles were reflected by ... The hydrophobic hemisphere of the Janus particles was exposed when a hydrophilic substrate surface was used, resulting in ... For example, a Janus particle may have one-half of its surface composed of hydrophilic groups and the other half hydrophobic ... The first type are particles which are truly amphiphilic and possess one hydrophobic and one hydrophilic side. The second type ...
The relaxation can distinguish among the hydrophobic and hydrophilic substrate. Although 3He and 129Xe have spin half but they ... However, the 21Ne (I=3/2), 83Kr(I=9/2) and 131Xe (I=3/2) have Quadrupolar moment.34 Quadrupolar interactions make these ... surface interaction studies, and neutron polarizing experiments. Spin exchange optical pumping (SEOP) is one of several ...
One face of the beta sheet and one side of the helix array are exposed to solvent and are therefore dominated by hydrophilic ... It is composed of repeating 20-30 amino acid stretches that are unusually rich in the hydrophobic amino acid leucine. These ... They are themselves not involved in protein-protein-interactions but help to present the adjacent LRR-domain for this purpose. ... The region between the helices and sheets is the protein's hydrophobic core and is tightly sterically packed with leucine ...
It is an amphiphile capable of withstanding hydrophilic and hydrophobic environments. The Gram-positive bacterial species ... participating in hydrophobic interactions within micelles. This antibiotic is synthesized by a linear nonribosomal peptide ... Grau A, Gómez Fernández JC, Peypoux F, Ortiz A (May 1999). "A study on the interactions of surfactin with phospholipid vesicles ... Deleu M, Bouffioux O, Razafindralambo H, Paquot M, Hbid C, Thonart P, Jacques P, Brasseur R (April 2003). "Interaction of ...
Whether or not the pan is hydrophilic or hydrophobic, the heat conductivity and capacity, surface roughness, and more all ... This eliminates the interactions between the denatured proteins on meat and the oil. In deep frying, the interactions are ... The value of each individual interaction may be small but when there are millions of interactions the overall force can be ... Thus there should be no interaction between the food and the container holding the oil. All the interactions will be between ...
  • Of special interest is the preferential enrichment of aromatic residues (for example, tryptophan [Trp]) in the interface between the hydrophilic aqueous phases and the hydrophobic bilayer core. (
  • Upon chemical reduction , the drug was converted to its cytotoxic and hydrophilic form and released from the carrier, via a drastic reversal in hydrophobicity, for DNA-binding. (
  • This simple method of hydrophobic entrapment and controlled release by chemical reduction and hydrophobicity reversal, exploiting the Pt( IV ) scaffold as a prodrug , could form the basis of other delivery strategies for targeted delivery of platinum drugs into cancer cells. (
  • Moreover, hydrophobicity of pipette tips can result in hydrophobic adsorption of biomolecules, causing inaccuracies and loss in precision during pipetting. (
  • Here, we report a hydrophobic block-hydrophilic polyelectrolyte block polymer that forms a simple one-dimensional periodic lamellar structure. (
  • The model has only two types of residues, hydrophobic and hydrophilic. (
  • One of the specific questions relates to a peculiar feature of integral membrane proteins: namely, a preference for aromatic (for example, Trp) residues located in the interfacial region between the hydrophobic core and the hydrophilic surface of the membrane. (
  • This adopts a layered arrangement comprising alternating sodium carboxylate hydrophilic layers and hydrophobic organic bilayers. (
  • Coupling interactions between voltage sensors of the sodium channel as revealed by site-specific measurements. (
  • Our dynamic contact-line model, in conjunction with its monolithic coupling system, unifies the simulation of various hydrophobic and hydrophilic solid-fluid-interaction phenomena and enables a broad range of challenging small-scale elastocapillary phenomena that were previously difficult or impractical to solve, such as the elastocapillary origami and self-assembly, dynamic contact angles of drops, capillary adhesion, as well as wetting and splashing on vibrating surfaces. (
  • This inorganic phosphate ion increases the toxin stability by neutralizing the positively charged basic amino acids of the monomers, creating possibilities for more Van Der Waals interactions. (
  • Separation mechanism based on hydrophobic (van der Waals) and polar interactions. (
  • Glycine and alanine are both small amino acids, but glycine prefers turns while alanine prefers helices, and glycine is extremely flexible and intermediate while alanine is hydrophobic. (
  • Since both of these amino acids are also hydrophobic this mutation is thought to have little interference with the folding and stability of the protein. (
  • Over the past few decades, the amorphous solid dispersions (ASDs) technique has emerged as a promising strategy to enhance the in vitro/in vivo characteristic of hydrophobic drugs. (
  • In vitro interactions of NP with cells might not correspond to their behavior in vivo [ 8 ]. (
  • A particular area of biophysical research in which Raman spectroscopy has great potential is the study of lipid-protein interactions. (
  • Proteins are embedded in the lipid bilayer by virtue of their hydrophilic and hydrophobic moieties expressed in the notion of hydrophobic coupling. (
  • The amphiphatic character of membrane-spanning proteins and lipid molecules implies that lipids and proteins self-assemble to avoid the high energetic cost of exposing hydrophobic moieties to water (1,2). (
  • The interaction - hydrophobic coupling - between lipids and membrane proteins is generally only slightly stronger than the interactions between lipids (3,4), suggesting an important role for unspecific lipid-protein hydrophobic interactions (3). (
  • Raman spectroscopy has immediate appeal in the study of lipid-protein interactions because it is a noninvasive and nondestructive technique, and the excitation wavelength can be chosen to be below the absorption frequency of water (13). (
  • Here, we first discuss the technical challenges and relevant Raman spectroscopic markers for investigating the role of lipid-protein interactions in fully hydrated protein-vesicle samples. (
  • Bile salts aid in forming lipid micelles, which create a hydrophilic surface with a hydrophobic core of lipid molecules, including FFA. (
  • Herein, we report the development of a novel strategy by combining hydrophobic derivatization and high pH strong cation exchange enrichment, which significantly expands the identification coverage of the methylproteome. (
  • unfortunately, a significant number of methylated peptides are highly hydrophilic and hardly retained during reversed-phase chromatography, making it difficult to be identified by conventional approaches. (
  • In this study, based on the combination of hydrophilic interaction liquid chromatography (HILIC) and reversed phase liquid chromatography (RPLC), an online two-dimensional liquid chromatography/triple quadrupole mass spectrometry method (2D-LC/TQMS) was developed for the simultaneous analysis of hydrophilic and hydrophobic metabolites of various biological samples. (
  • In contrast, active targeting is based on molecular ligand-receptor interactions and is only possible when the receptor and ligand come in close proximity (less than 0.5 mm) after the drug has circulated through the blood and extravasated in the tumor tissue [ 7 ]. (
  • Therefore, by gaining deeper insight into interactions of NPs with cells and the tumor microenvironment, we may begin to maximize the potential of nanomedicine in cancer. (
  • By including sequence independent local interactions, which qualitatively reproduce local properties of functional proteins, the dominance of a native state for many sequences is observed. (
  • The number of available high-resolution structures of integral membrane spanning proteins is increasing, and there is mounting evidence for regulation of membrane proteins by the host bilayer membrane through the hydrophobic coupling between membrane and proteins (4,5). (
  • Here, the packing arrangement is different with the central hydrophilic (NaO2)∞ core surrounded by a wrapping of disordered alkyl groups. (
  • Most pipette tips on the market are manufactured with hydrophobic polymers that are able to repel high surface tension liquids, yet they lack in performance when low surface tension liquids and viscous fluids are involved. (
  • It is a hydrophobic phase with pronounced hydrophilic properties. (
  • Responsive photonic crystals have been developed for chemical sensing using the variation of optical properties due to interaction with their environment. (
  • Based on high-purity NUCLEODUR silica gel, a polar group was embedded in a hydrophobic C18. (
  • Platinum-based anticancer drugs constitute some of most effective chemotherapeutic regimes, but they are limited by high toxicities and severe side-effects arising from premature aquation and non-specific interactions. (
  • This results in a responsive photonic crystal that can be tuned via swelling of the hydrophilic layers by contact with a fluid reservoir. (
  • Phenylalanine and leucine are both hydrophobic, however phenylalanine is large, aromatic and strand-preferring, while leucine is medium in size and prefers to be in a helix. (
  • For proliferation a hydrophobic and large size third position amino acid was crucial, while adhesion inhibition and desorption needed a small hydrophilic second position amino acid. (
  • Like other members of the lipocalin family, BLG these specific interactions have been shown to be critical for has a -barrel fold with a large internal cavity that binds dimer stability (Kobayashi et al. (
  • The reason for this and its relation to hydrophobic coupling is not clear despite intensive research. (
  • In absence of local interactions, native structure formation does not occur for the temperatures considered. (
  • Newer strategies recognize the close biologic interactions between the skeletal cells and the immune cells. (
  • In systems in which monovalent and divalent ions coexist, such as physiological salt solutions, it is unclear how these ions contribute to the osmotic and electrostatic interactions. (
  • Polymers with hydrophobic backbones precipitate when the electrostatic interactions are compensated. (
  • Aside from coating with amphiphilic molecules, such as phospholipids, polymers, and saccharides [ 13 - 15 ], one effective method to stabilize QDs is to incorporate them into an appropriate host matrix such as organic polymers, carbon nanomaterials, and inorganic materials through in situ nanocrystal growth, electrostatic interactions, and cross-linking processes [ 16 - 18 ]. (
  • Molecular dynamics simulations are used to compare the forces and Gibbs free energies associated with bringing small hydrophobic and hydrophilic solutes together in an aqueous solution at different temperatures between 280 and 360 °K. For the hydrophilic solutes, different relative orientations are used to distinguish between direct, intersolute hydrogen bonds (Hbond) and solutes simultaneously hydrogen bonding to a solvent water bridge. (
  • Interestingly, the temperature dependence of the hydrophobic and directly hydrogen bonding solutes turns out to be opposite to that of the bridged hydrophilic solutes, with the Δ G becoming more negative for the former and less negative for the latter with increasing temperature. (
  • Specifically, the more hydrophilic nanoparticles with a higher number of hydroxyl groups bound to the surface of the protein via hydrogen bonds, which stabilized the protein without inducing large conformational changes in the protein structure. (
  • Multiwalled carbon nanotubes ( MWCNTs ) are highly ordered hexagonal lattices of carbon atoms arranged into cylinders by hydrogen bonding, dipolar forces, hydrophilic or hydrophobic interactions, gravity, and other forces. (
  • In contrast, we were unable to identify electron density for hydrophobic fragments, confirming that hydrophobic interactions are important for inhibitor affinity but of minor importance for ligand recognition. (
  • Non-sieve SPE cartridges rely on chemical interactions such as hydrophobic, hydrophilic, ion-exchange, or affinity interactions to selectively retain analytes. (
  • The SBIG is a clearinghouse for discussions and interactions between scientists interested in all aspects of molecular structure, from experimental determination by x-ray crystallography, electron microscopy, mass spectrometry, and NMR, to theoretical and computational biology and biophysics, and to the biological application of structural data. (
  • The consequences of the above differences on the molecular organization, interactions and functional properties will be discussed. (
  • 18. Molecular dynamics analysis of conserved hydrophobic and hydrophilic bond-interaction networks in ErbB family kinases. (
  • Our explicit solvent molecular dynamics (MD) simulation results show that bolaamphiphiles rapidly cover RNA duplexes due to the strong interaction between the cationic head groups in bolaamphiphiles and the negative charges on the phosphate groups of the RNA backbone. (
  • Here, we focused on the effect of hydroxylation - a common strategy for solubilizing and functionalizing fullerene - on protein-nanoparticle interactions using a model protein, ubiquitin. (
  • In contrast, fullerene derivatives with a smaller number of hydroxyl groups buried their hydrophobic surface inside the protein, thereby causing protein denaturation. (
  • The direct sequence of ATGL cDNA reveals that a patient is a homozygote for the 4-bp deletion, leading to a premature stop codon and causes the lack of the C terminus of the protein including the hydrophobic domain. (
  • Our results suggest that a screening approach using protein crystallography is particularly useful to identify universal fragments for the conserved hydrophilic recognition sites found in target families such as SH2 domains, phosphatases, kinases, proteases, and esterases. (
  • Our results are consistent with the most recent X-ray crystallographic and simulation studies but disagree with an earlier interpretation of nuclear magnetic resonance (NMR) experiments probing protein-water interactions. (
  • The interfacial potential energies were calculated for the crystal-water interactions and compared with experimental enthalpy values obtained from contact angle measurements. (
  • An understanding of the influence of hydrophilic and hydrophobic interactions on the dynamics of solvating water molecules is important in a diverse range of phenomena. (
  • Subtle interactions between the surface atoms of QDs and surrounding molecules can significantly influence the photoluminescence characteristics of QDs. (
  • We show that, at least semiquantitatively, the measured nuclear Overhauser effects indicating the proximity of water to the methyl groups lining the nonpolar cavity can, in all likelihood, be attributed to interactions with buried and surface water molecules near the cavity. (
  • A coarse-grained HbS model, which contains hydrophilic and hydrophobic particles, is constructed to match the structural properties and physical description (including crowding effects) of HbS. (
  • The substrate is bound to an hydrophobic anchor, which binds to reversed-phase silica gel, thus immobilizing the substrate. (
  • Significant amounts of large hydrophilic substrates that are bound to acridone can be found in the liquid phase. (
  • Different hydrophilic substrates have been bound to these anchors. (
  • The physisorption and mechanical interlocking mechanisms are responsible for such improvement due to the simultaneous creation of hydrophobic and hydrophilic interactions of the thermosensitive hydrogel at temperatures higher than the lower critical solution temperature (LCST), with the porcine tissue. (
  • The thermodynamic interaction between a substance and WATER . (
  • Results: The results showed that plasma treatment improved the hydrophilic property of PCL scaffolds. (
  • Bolaamphiphiles have two positively charged hydrophilic head groups connected by a hydrophobic chain and they have a relatively low toxicity level when compared to lipids and can persist in the blood for long period of time. (
  • These results increase our understanding of the interaction between expansin and cellulose, and provide evidence for expansin treatment as a promising strategy to enhance enzymatic hydrolysis of lignocellulose. (
  • An important common feature of DNA and PAANa is that the backbone of both polymers is hydrophobic. (
  • The comparism of the interaction with reversed phase silica for the steroid anchors showed a considerable improvement versus acridone. (
  • The use of hydrophilic interaction chromatography (HILIC) combined with reversed phase (RP) separations has already been demonstrated as a very orthogonal combination, which allows attaining increased resolving power. (
  • The objectives were to report siblings with neutral lipid storage disease with myopathy (NLSDM) with a novel mutation of adipose triglyceride lipase (ATGL) and determine whether the C-terminal part of ATGL containing the hydrophobic region plays a role in the interaction with LDs. (
  • 10. Role of epidermal growth factor receptor signaling in the interaction of Neisseria meningitidis with endothelial cells. (
  • The choice of sorbent depends on the specific analytes and the type of interactions required for efficient extraction. (
  • 11. Stretch-induced fetal type II cell differentiation is mediated via ErbB1-ErbB4 interactions. (