Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.
Diazomethane is an extremely hazardous and unstable organic compound, (CH2)N=N=O, with a methane substituted diazo group, that is highly explosive when heated, shocked or contaminated, and used as a powerful methylating agent in chemical syntheses, but its production and handling require special expertise and equipment due to the high risks involved.
Enzymes that specifically hydroxylate PROLINE residues on proteins.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
The rate dynamics in chemical or physical systems.
The covalent bonding of an alkyl group to an organic compound. It can occur by a simple addition reaction or by substitution of another functional group.
The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.
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.
A chromatographic technique that utilizes the ability of biological molecules to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
A water-soluble, enzyme co-factor present in minute amounts in every living cell. It occurs mainly bound to proteins or polypeptides and is abundant in liver, kidney, pancreas, yeast, and milk.
Adenosine 5'-(trihydrogen diphosphate). An adenine nucleotide containing two phosphate groups esterified to the sugar moiety at the 5'-position.
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.
Cyanogen bromide (CNBr). A compound used in molecular biology to digest some proteins and as a coupling reagent for phosphoroamidate or pyrophosphate internucleotide bonds in DNA duplexes.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
An enzyme that catalyzes the conversion of L-glutamate and water to 2-oxoglutarate and NH3 in the presence of NAD+. (From Enzyme Nomenclature, 1992) EC 1.4.1.2.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
An essential amino acid. It is often added to animal feed.
Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)
Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.
The sum of the weight of all the atoms in a molecule.
A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
A measure of the binding strength between antibody and a simple hapten or antigen determinant. It depends on the closeness of stereochemical fit between antibody combining sites and antigen determinants, on the size of the area of contact between them, and on the distribution of charged and hydrophobic groups. It includes the concept of "avidity," which refers to the strength of the antigen-antibody bond after formation of reversible complexes.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.

Receptor-mediated targeting of fluorescent probes in living cells. (1/2197)

A strategy was developed to label specified sites in living cells with a wide selection of fluorescent or other probes and applied to study pH regulation in Golgi. cDNA transfection was used to target a single-chain antibody to a specified site such as an organelle lumen. The targeted antibody functioned as a high affinity receptor to trap cell-permeable hapten-fluorophore conjugates. Synthesized conjugates of a hapten (4-ethoxymethylene-2-phenyl-2-oxazolin-5-one, phOx) and fluorescent probes (Bodipy Fl, tetramethylrhodamine, fluorescein) were bound with high affinity (approximately 5 nM) and specific localization to the single-chain antibody expressed in the endoplasmic reticulum, Golgi, and plasma membrane of living Chinese hamster ovary cells. Using the pH-sensitive phOx-fluorescein conjugate and ratio imaging microscopy, pH was measured in the lumen of Golgi (pH 6.25 +/- 0.06). Measurements of pH-dependent vacuolar H+/ATPase pump activity and H+ leak in Golgi provided direct evidence that resting Golgi pH is determined by balanced leak-pump kinetics rather than the inability of the H+/ATPase to pump against an electrochemical gradient. Like expression of the green fluorescent protein, the receptor-mediated fluorophore targeting approach permits specific intracellular fluorescence labeling. A significant advantage of the new approach is the ability to target chemical probes with custom-designed spectral and indicator properties.  (+info)

Interaction of purified human proteinase 3 (PR3) with reconstituted lipid bilayers. (2/2197)

Proteinase 3 (PR3), the major target autoantigen in Wegener's granulomatosis is a serine proteinase that is normally stored intracellularly in the primary granules of quiescent neutrophils and monocytes. Upon cell activation, a significant portion of this antigen is detected on the cell surface membrane. The nature of the association of PR3 with the membrane and its functional significance are unknown. We investigated the interaction of purified human PR3 with mixtures of zwitterionic (dimyristoyl-L-alpha-phosphatidylcholine, DMPC) and anionic (dimyristoyl-L-alpha-phosphatidylglycerol, DMPG) phospholipids in reconstituted lipid bilayers using differential scanning calorimetry and lipid photolabeling, and measured the affinity of this interaction using spectrophotometry. Two other primary granule constituents, human neutrophil elastase (HNE) and myeloperoxidase (MPO) were investigated for comparison. In calorimetric assays, using lipid vesicles of mixed DMPC/DMPG, increasing PR3 concentrations (protein/lipid molar ratio from 0 to 1 : 110) induced a significant decrease of the main chain transition enthalpy and a shift in chain melting temperatures which is indicative of partial insertion of PR3 into the hydrophobic region of the lipid membranes. This was confirmed by hydrophobic photolabeling using liposomes containing trace amounts of the photoactivable [125I]-labeled phosphatidylcholine analog TID-PC/16. The molar affinity of PR3, HNE, and MPO to lipid vesicles of different DMPC/DMPG ratios was then determined by spectrophotometry. At a DMPC/DMPG ratio of 1 : 1, molar affinities of PR3, Kd = 4.5 +/- 0.3 microm; HNE, 14.5 +/- 1.2 microm; and MPO, 50 +/- 5 microm (n = 3) were estimated. The lipid-associated PR3 exhibited two-fold lower Vmax and Km values, and its enzyme activity was slightly more inhibited (Ki) by the natural alpha1-proteinase inhibitor (alpha1-PI) or an autoantibody to PR3.  (+info)

Affinity labelling with MgATP analogues reveals coexisting Na+ and K+ forms of the alpha-subunits of Na+/K+-ATPase. (3/2197)

To test the hypothesis that Na+/K+-ATPase works as an (alpha beta)2-diprotomer with interacting catalytic alpha-subunits, tryptic digestion of pig kidney enzyme, that had been inactivated with substitution-inert MgATP complex analogues, was performed. This led to the demonstration of coexisting C-terminal Na+-like 80-kDa as well as K+-like 60-kDa peptides and N-terminal 40-kDa peptides of the alpha-subunit. To localize the ATP binding sites on tryptic peptides, studies with radioactive MgATP complex analogues were performed: Co(NH3)4-8-N3-ATP specifically modified the E2ATP (low affinity) binding site of Na+/K+-ATPase with an inactivation rate constant (k2) of 12 x 10-3.min-1 at 37 degrees C and a dissociation constant (Kd) of 207 +/- 28 microm. Tryptic digestion of the [gamma32P]Co(NH3)4-8-N3-ATP-inactivated and photolabelled alpha-subunit (Mr = 100 kDa) led, in the absence of univalent cations, to a K+-like C-terminal 60-kDa fragment which was labelled in addition to an unlabelled Na+-like C-terminal 80-kDa fragment. Tryptic digestion of [alpha32P]-or [gamma32P]Cr(H2O)4ATP - bound to the E1ATP (high affinity) site - led to the labelling of a Na+-like 80-kDa fragment besides the immediate formation of an unlabelled K+-like N-terminal 40-kDa fragment and a C-terminal 60-kDa fragment. Because a labelled Na+-like 80-kDa fragment cannot result from an unlabelled K+-like 60-kDa fragment, and because unlabelled alpha-subunits did not show any catalytic activity, the findings are consistent with a situation in which Na+- and K+-like conformations are stabilized by tight binding of substitution-inert MgATP complex analogues to the E1ATP and E2ATP sites. Hence, all data are consistent with the hypothesis that ATP binding induces coexisting Na+ and K+ conformations within an (alphabeta)2-diprotomeric Na+/K+-ATPase.  (+info)

Identification, purification, and characterization of the rat liver golgi membrane ATP transporter. (4/2197)

Phosphorylation of secretory and integral membrane proteins and of proteoglycans also occurs in the lumen of the Golgi apparatus. ATP, the phosphate donor in these reactions, must first cross the Golgi membrane before it can serve as substrate. The existence of a specific ATP transporter in the Golgi membrane has been previously demonstrated in vitro using intact Golgi membrane vesicles from rat liver and mammary gland. We have now identified and purified the rat liver Golgi membrane ATP transporter. The transporter was purified to apparent homogeneity by a combination of conventional ion exchange, dye color, and affinity chromatography. An approximately 70,000-fold purification (2% yield) was achieved starting from crude rat liver Golgi membranes. A protein with an apparent molecular mass of 60 kDa was identified as the putative transporter by a combination of column chromatography, photoaffinity labeling with an analog of ATP, and native functional size determination on a glycerol gradient. The purified transporter appears to exist as a homodimer within the Golgi membrane, and when reconstituted into phosphatidylcholine liposomes, was active in ATP but not nucleotide sugar or adenosine 3'-phosphate 5'-phosphosulfate transport. The transport activity was saturable with an apparent Km very similar to that of intact Golgi vesicles.  (+info)

Ectodomain cleavage and shedding of the type III transforming growth factor-beta receptor in lung membranes effect of temperature, ligand binding and membrane solubilization. (5/2197)

Previous studies from our laboratory [Philip, A. & O'Connor-McCourt, M. D. (1991) J. Biol. Chem. 266, 22290--22296] have shown that the lung exhibited the highest uptake of circulating [125I]-transforming growth factor-beta1 (TGF-beta1) on a per gram basis. This observation, together with the lack of information on TGF-beta receptor expression in the lung, prompted us to attempt to characterize TGF-beta receptors in this tissue. In the present report we show that the type III TGF-beta receptor is the most abundant TGF-beta binding protein in rat lung membranes and that it exhibits a 10-fold higher affinity for TGF-beta2 than for TGF-beta1. We observed that the majority of the type III receptor population in lung membranes is cleaved at a site in the central portion of the ectodomain, the resulting two fragments (95 kDa and 58 kDa) being held together by disulfide bonds. Furthermore, we demonstrate that a soluble form of the ectodomain of the type III receptor is shed from rat lung membranes in an efficient manner, with protease cleavage occurring at a site close to the transmembrane domain. This shedding is controllable by temperature, thus providing a system to study the mechanism of ectodomain release. Using this system, we show that the shedding is inhibited by prior ligand binding and by membrane solubilization. The identification of a membrane preparation which exhibits controllable and quantitative release of the type III receptor ectodomain provides a unique cell-free system for further studies of the mechanism of shedding of the type III TGF-beta receptor ectodomain.  (+info)

Photoaffinity labeling and mass spectrometry identify ribosomal protein S3 as a potential target for hybrid polar cytodifferentiation agents. (6/2197)

The ability of a novel class of hybrid polar compounds (HPCs) to induce differentiation and consequent cessation of proliferation of transformed cells has led to their development as potential chemotherapeutic agents in the treatment of cancer. Suberoylanilide hydroxamic acid (SAHA) is a prototype of a family of hydroxamic acid based compounds (SAHA-like HPCs) that can, at micromolar concentrations, induce a variety of transformed cell lines to differentiate. The mechanism of action of the HPCs is not entirely understood. Searching for a cellular target of the SAHA-like HPCs, we synthesized a photoaffinity labeling reagent structurally based on SAHA, and probed for SAHA-binding proteins in murine erythroleukemia (MEL) cells. Photoaffinity labeling in cell free extracts identified a 32-kDa protein (p32) that was specifically labeled by the photoaffinity reagent. Cell fractionation assays localized p32 to the P100 fraction. p32 was partially purified and identified by mass spectrometry as the 40 S ribosomal protein S3. Expression of epitope-tagged S3 in bacterial lysates followed by photoaffinity labeling confirmed its specific labeling. Identification of a cytodifferentiation agent target may shed light on the mechanism by which the SAHA-like HPCs exert their antitumor effects.  (+info)

Comparison of paclitaxel-, 5-fluoro-2'-deoxyuridine-, and epidermal growth factor (EGF)-induced apoptosis. Evidence for EGF-induced anoikis. (7/2197)

Epidermal growth factor (EGF), a hormone that stimulates proliferation of many cell types, induces apoptosis in some cell lines that overexpress the EGF receptor. To evaluate the mechanism of EGF-induced apoptosis, MDA-MB-468 breast cancer cells were examined by microscopy, flow cytometry, immunoblotting, enzyme assays, and affinity labeling after treatment with EGF, paclitaxel, or 5-fluoro-2'-deoxyuridine (5FUdR). Apoptosis induced by all three agents was accompanied by activation of caspases-3, -6, and -7, as indicated by disappearance of the corresponding zymogens from immunoblots, cleavage of substrate polypeptides in situ, and detection of active forms of these caspases in cytosol and nuclei using fluorogenic assays and affinity labeling. Further analysis indicated involvement of the cytochrome c/Apaf-1/caspase-9 pathway of caspase activation, but not the Fas/Fas ligand pathway. Interestingly, caspase activation was consistently lower after EGF treatment than after paclitaxel or 5FUdR treatment. Additional experiments revealed that the majority of cells detaching from the substratum after EGF (but not paclitaxel or 5FUdR) were morphologically normal and retained the capacity to readhere, suggesting that EGF-induced apoptosis involves cell detachment followed by anoikis. These observations not only indicate that EGF- and chemotherapy-induced apoptosis in this cell line involve the same downstream pathways but also suggest that detachment-induced apoptosis is responsible for the paradoxical antiproliferative effects of EGF.  (+info)

Opening mechanism of a cyclic nucleotide-gated channel based on analysis of single channels locked in each liganded state. (8/2197)

Cyclic nucleotide-gated channels contain four subunits, each with a binding site for cGMP or cAMP in the cytoplasmic COOH-terminal domain. Previous studies of the kinetic mechanism of activation have been hampered by the complication that ligands are continuously binding and unbinding at each of these sites. Thus, even at the single channel level, it has been difficult to distinguish changes in behavior that arise from a channel with a fixed number of ligands bound from those that occur upon the binding and unbinding of ligands. For example, it is often assumed that complex behaviors like multiple conductance levels and bursting occur only as a consequence of changes in the number of bound ligands. We have overcome these ambiguities by covalently tethering one ligand at a time to single rod cyclic nucleotide-gated channels (Ruiz, ML., and J.W. Karpen. 1997. Nature. 389:389-392). We find that with a fixed number of ligands locked in place the channel freely moves between three conductance states and undergoes bursting behavior. Furthermore, a thorough kinetic analysis of channels locked in doubly, triply, and fully liganded states reveals more than one kinetically distinguishable state at each conductance level. Thus, even when the channel contains a fixed number of bound ligands, it can assume at least nine distinct states. Such complex behavior is inconsistent with simple concerted or sequential allosteric models. The data at each level of liganding can be successfully described by the same connected state model (with different rate constants), suggesting that the channel undergoes the same set of conformational changes regardless of the number of bound ligands. A general allosteric model, which postulates one conformational change per subunit in both the absence and presence of ligand, comes close to providing enough kinetically distinct states. We propose an extension of this model, in which more than one conformational change per subunit can occur during the process of channel activation.  (+info)

Affinity labels are chemical probes or reagents that can selectively and covalently bind to a specific protein or biomolecule based on its biological function or activity. These labels contain a functional group that interacts with the target molecule, often through non-covalent interactions such as hydrogen bonding, van der Waals forces, or ionic bonds. Once bound, the label then forms a covalent bond with the target molecule, allowing for its isolation and further study.

Affinity labels are commonly used in biochemistry and molecular biology research to identify and characterize specific proteins, enzymes, or receptors. They can be designed to bind to specific active sites, binding pockets, or other functional regions of a protein, allowing researchers to study the structure-function relationships of these molecules.

One example of an affinity label is a substrate analogue that contains a chemically reactive group. This type of affinity label can be used to identify and characterize enzymes by binding to their active sites and forming a covalent bond with the enzyme. The labeled enzyme can then be purified and analyzed to determine its structure, function, and mechanism of action.

Overall, affinity labels are valuable tools for studying the properties and functions of biological molecules in vitro and in vivo.

Diazomethane is a highly reactive, explosive organic compound with the chemical formula CH2N2. It is a colorless gas or pale yellow liquid that is used as a methylating agent in organic synthesis. Diazomethane is prepared by the reaction of nitrosomethane with a base such as potassium hydroxide.

It is important to handle diazomethane with care, as it can be explosive and toxic. It should only be used in well-ventilated areas, and protective equipment such as gloves and safety glasses should be worn. Diazomethane should not be stored for long periods of time, as it can decompose spontaneously and release nitrogen gas.

Diazomethane is used to introduce methyl groups into organic molecules in a process called methylation. It reacts with carboxylic acids to form methyl esters, and with phenols to form methyl ethers. Diazomethane is also used to synthesize other organic compounds such as pyrazoles and triazoles.

It is important to note that the use of diazomethane in the laboratory has declined due to its hazardous nature, and safer alternatives are now available for many of its applications.

Prolyl hydroxylases are a group of enzymes that play a crucial role in the regulation of collagen synthesis and stability. These enzymes catalyze the hydroxylation of specific proline residues in the collagen molecule, which is an essential step for the formation of stable collagen triple helices. Prolyl hydroxylases require molecular oxygen, iron, and α-ketoglutarate as cofactors to carry out this reaction. In humans, there are four known prolyl hydroxylase isoforms (PHD1, PHD2, PHD3, and SMHL), which have distinct but overlapping substrate specificities and tissue distributions. Mutations in the genes encoding these enzymes can lead to various connective tissue disorders, such as osteogenesis imperfecta and Ehlers-Danlos syndrome. Additionally, prolyl hydroxylases have been identified as key regulators of hypoxia-inducible factor (HIF) stability, making them important players in the cellular response to low oxygen levels (hypoxia).

In the context of medical and biological sciences, a "binding site" refers to a specific location on a protein, molecule, or cell where another molecule can attach or bind. This binding interaction can lead to various functional changes in the original protein or molecule. The other molecule that binds to the binding site is often referred to as a ligand, which can be a small molecule, ion, or even another protein.

The binding between a ligand and its target binding site can be specific and selective, meaning that only certain ligands can bind to particular binding sites with high affinity. This specificity plays a crucial role in various biological processes, such as signal transduction, enzyme catalysis, or drug action.

In the case of drug development, understanding the location and properties of binding sites on target proteins is essential for designing drugs that can selectively bind to these sites and modulate protein function. This knowledge can help create more effective and safer therapeutic options for various diseases.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Alkylation, in the context of medical chemistry and toxicology, refers to the process of introducing an alkyl group (a chemical moiety made up of a carbon atom bonded to one or more hydrogen atoms) into a molecule, typically a biomolecule such as a protein or DNA. This process can occur through various mechanisms, including chemical reactions with alkylating agents.

In the context of cancer therapy, alkylation is used to describe a class of chemotherapeutic drugs known as alkylating agents, which work by introducing alkyl groups onto DNA molecules in rapidly dividing cells. This can lead to cross-linking of DNA strands and other forms of DNA damage, ultimately inhibiting cell division and leading to the death of cancer cells. However, these agents can also affect normal cells, leading to side effects such as nausea, hair loss, and increased risk of infection.

It's worth noting that alkylation can also occur through non-chemical means, such as in certain types of radiation therapy where high-energy particles can transfer energy to electrons in biological molecules, leading to the formation of reactive radicals that can react with and alkylate DNA.

"Competitive binding" is a term used in pharmacology and biochemistry to describe the behavior of two or more molecules (ligands) competing for the same binding site on a target protein or receptor. In this context, "binding" refers to the physical interaction between a ligand and its target.

When a ligand binds to a receptor, it can alter the receptor's function, either activating or inhibiting it. If multiple ligands compete for the same binding site, they will compete to bind to the receptor. The ability of each ligand to bind to the receptor is influenced by its affinity for the receptor, which is a measure of how strongly and specifically the ligand binds to the receptor.

In competitive binding, if one ligand is present in high concentrations, it can prevent other ligands with lower affinity from binding to the receptor. This is because the higher-affinity ligand will have a greater probability of occupying the binding site and blocking access to the other ligands. The competition between ligands can be described mathematically using equations such as the Langmuir isotherm, which describes the relationship between the concentration of ligand and the fraction of receptors that are occupied by the ligand.

Competitive binding is an important concept in drug development, as it can be used to predict how different drugs will interact with their targets and how they may affect each other's activity. By understanding the competitive binding properties of a drug, researchers can optimize its dosage and delivery to maximize its therapeutic effect while minimizing unwanted side effects.

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.

Affinity chromatography is a type of chromatography technique used in biochemistry and molecular biology to separate and purify proteins based on their biological characteristics, such as their ability to bind specifically to certain ligands or molecules. This method utilizes a stationary phase that is coated with a specific ligand (e.g., an antibody, antigen, receptor, or enzyme) that selectively interacts with the target protein in a sample.

The process typically involves the following steps:

1. Preparation of the affinity chromatography column: The stationary phase, usually a solid matrix such as agarose beads or magnetic beads, is modified by covalently attaching the ligand to its surface.
2. Application of the sample: The protein mixture is applied to the top of the affinity chromatography column, allowing it to flow through the stationary phase under gravity or pressure.
3. Binding and washing: As the sample flows through the column, the target protein selectively binds to the ligand on the stationary phase, while other proteins and impurities pass through. The column is then washed with a suitable buffer to remove any unbound proteins and contaminants.
4. Elution of the bound protein: The target protein can be eluted from the column using various methods, such as changing the pH, ionic strength, or polarity of the buffer, or by introducing a competitive ligand that displaces the bound protein.
5. Collection and analysis: The eluted protein fraction is collected and analyzed for purity and identity, often through techniques like SDS-PAGE or mass spectrometry.

Affinity chromatography is a powerful tool in biochemistry and molecular biology due to its high selectivity and specificity, enabling the efficient isolation of target proteins from complex mixtures. However, it requires careful consideration of the binding affinity between the ligand and the protein, as well as optimization of the elution conditions to minimize potential damage or denaturation of the purified protein.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Biotin is a water-soluble vitamin, also known as Vitamin B7 or Vitamin H. It is a cofactor for several enzymes involved in metabolism, particularly in the synthesis and breakdown of fatty acids, amino acids, and carbohydrates. Biotin plays a crucial role in maintaining healthy skin, hair, nails, nerves, and liver function. It is found in various foods such as nuts, seeds, whole grains, milk, and vegetables. Biotin deficiency is rare but can occur in people with malnutrition, alcoholism, pregnancy, or certain genetic disorders.

Adenosine diphosphate (ADP) is a chemical compound that plays a crucial role in energy transfer within cells. It is a nucleotide, which consists of a adenosine molecule (a sugar molecule called ribose attached to a nitrogenous base called adenine) and two phosphate groups.

In the cell, ADP functions as an intermediate in the conversion of energy from one form to another. When a high-energy phosphate bond in ADP is broken, energy is released and ADP is converted to adenosine triphosphate (ATP), which serves as the main energy currency of the cell. Conversely, when ATP donates a phosphate group to another molecule, it is converted back to ADP, releasing energy for the cell to use.

ADP also plays a role in blood clotting and other physiological processes. In the coagulation cascade, ADP released from damaged red blood cells can help activate platelets and initiate the formation of a blood clot.

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.

Cyanogen bromide is a solid compound with the chemical formula (CN)Br. It is a highly reactive and toxic substance that is used in research and industrial settings for various purposes, such as the production of certain types of resins and gels. Cyanogen bromide is an alkyl halide, which means it contains a bromine atom bonded to a carbon atom that is also bonded to a cyano group (a nitrogen atom bonded to a carbon atom with a triple bond).

Cyanogen bromide is classified as a class B poison, which means it can cause harm or death if swallowed, inhaled, or absorbed through the skin. It can cause irritation and burns to the eyes, skin, and respiratory tract, and prolonged exposure can lead to more serious health effects, such as damage to the nervous system and kidneys. Therefore, it is important to handle cyanogen bromide with care and to use appropriate safety precautions when working with it.

A peptide fragment is a short chain of amino acids that is derived from a larger peptide or protein through various biological or chemical processes. These fragments can result from the natural breakdown of proteins in the body during regular physiological processes, such as digestion, or they can be produced experimentally in a laboratory setting for research or therapeutic purposes.

Peptide fragments are often used in research to map the structure and function of larger peptides and proteins, as well as to study their interactions with other molecules. In some cases, peptide fragments may also have biological activity of their own and can be developed into drugs or diagnostic tools. For example, certain peptide fragments derived from hormones or neurotransmitters may bind to receptors in the body and mimic or block the effects of the full-length molecule.

Indicators and reagents are terms commonly used in the field of clinical chemistry and laboratory medicine. Here are their definitions:

1. Indicator: An indicator is a substance that changes its color or other physical properties in response to a chemical change, such as a change in pH, oxidation-reduction potential, or the presence of a particular ion or molecule. Indicators are often used in laboratory tests to monitor or signal the progress of a reaction or to indicate the end point of a titration. A familiar example is the use of phenolphthalein as a pH indicator in acid-base titrations, which turns pink in basic solutions and colorless in acidic solutions.

2. Reagent: A reagent is a substance that is added to a system (such as a sample or a reaction mixture) to bring about a chemical reaction, test for the presence or absence of a particular component, or measure the concentration of a specific analyte. Reagents are typically chemicals with well-defined and consistent properties, allowing them to be used reliably in analytical procedures. Examples of reagents include enzymes, antibodies, dyes, metal ions, and organic compounds. In laboratory settings, reagents are often prepared and standardized according to strict protocols to ensure their quality and performance in diagnostic tests and research applications.

Glutamate Dehydrogenase (GLDH or GDH) is a mitochondrial enzyme that plays a crucial role in the metabolism of amino acids, particularly within liver and kidney tissues. It catalyzes the reversible oxidative deamination of glutamate to alpha-ketoglutarate, which links amino acid metabolism with the citric acid cycle and energy production. This enzyme is significant in clinical settings as its levels in blood serum can be used as a diagnostic marker for diseases that damage liver or kidney cells, since these cells release GLDH into the bloodstream upon damage.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

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.

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

Cysteine is a semi-essential amino acid, which means that it can be produced by the human body under normal circumstances, but may need to be obtained from external sources in certain conditions such as illness or stress. Its chemical formula is HO2CCH(NH2)CH2SH, and it contains a sulfhydryl group (-SH), which allows it to act as a powerful antioxidant and participate in various cellular processes.

Cysteine plays important roles in protein structure and function, detoxification, and the synthesis of other molecules such as glutathione, taurine, and coenzyme A. It is also involved in wound healing, immune response, and the maintenance of healthy skin, hair, and nails.

Cysteine can be found in a variety of foods, including meat, poultry, fish, dairy products, eggs, legumes, nuts, seeds, and some grains. It is also available as a dietary supplement and can be used in the treatment of various medical conditions such as liver disease, bronchitis, and heavy metal toxicity. However, excessive intake of cysteine may have adverse effects on health, including gastrointestinal disturbances, nausea, vomiting, and headaches.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

Lysine is an essential amino acid, which means that it cannot be synthesized by the human body and must be obtained through the diet. Its chemical formula is (2S)-2,6-diaminohexanoic acid. Lysine is necessary for the growth and maintenance of tissues in the body, and it plays a crucial role in the production of enzymes, hormones, and antibodies. It is also essential for the absorption of calcium and the formation of collagen, which is an important component of bones and connective tissue. Foods that are good sources of lysine include meat, poultry, fish, eggs, and dairy products.

"Spin labels" are a term used in the field of magnetic resonance, including nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR). They refer to molecules or atoms that have been chemically attached to a system of interest and possess a stable, unpaired electron. This unpaired electron behaves like a tiny magnet and can be manipulated using magnetic fields and radiofrequency pulses in EPR experiments. The resulting changes in the electron's spin state can provide information about the local environment, dynamics, and structure of the system to which it is attached. Spin labels are often used in biochemistry and materials science to study complex biological systems or materials at the molecular level.

Peptide mapping is a technique used in proteomics and analytical chemistry to analyze and identify the sequence and structure of peptides or proteins. This method involves breaking down a protein into smaller peptide fragments using enzymatic or chemical digestion, followed by separation and identification of these fragments through various analytical techniques such as liquid chromatography (LC) and mass spectrometry (MS).

The resulting peptide map serves as a "fingerprint" of the protein, providing information about its sequence, modifications, and structure. Peptide mapping can be used for a variety of applications, including protein identification, characterization of post-translational modifications, and monitoring of protein degradation or cleavage.

In summary, peptide mapping is a powerful tool in proteomics that enables the analysis and identification of proteins and their modifications at the peptide level.

Molecular weight, also known as molecular mass, is the mass of a molecule. It is expressed in units of atomic mass units (amu) or daltons (Da). Molecular weight is calculated by adding up the atomic weights of each atom in a molecule. It is a useful property in chemistry and biology, as it can be used to determine the concentration of a substance in a solution, or to calculate the amount of a substance that will react with another in a chemical reaction.

Adenosine is a purine nucleoside that is composed of a sugar (ribose) and the base adenine. It plays several important roles in the body, including serving as a precursor for the synthesis of other molecules such as ATP, NAD+, and RNA.

In the medical context, adenosine is perhaps best known for its use as a pharmaceutical agent to treat certain cardiac arrhythmias. When administered intravenously, it can help restore normal sinus rhythm in patients with paroxysmal supraventricular tachycardia (PSVT) by slowing conduction through the atrioventricular node and interrupting the reentry circuit responsible for the arrhythmia.

Adenosine can also be used as a diagnostic tool to help differentiate between narrow-complex tachycardias of supraventricular origin and those that originate from below the ventricles (such as ventricular tachycardia). This is because adenosine will typically terminate PSVT but not affect the rhythm of VT.

It's worth noting that adenosine has a very short half-life, lasting only a few seconds in the bloodstream. This means that its effects are rapidly reversible and generally well-tolerated, although some patients may experience transient symptoms such as flushing, chest pain, or shortness of breath.

NAD (Nicotinamide Adenine Dinucleotide) is a coenzyme found in all living cells. It plays an essential role in cellular metabolism, particularly in redox reactions, where it acts as an electron carrier. NAD exists in two forms: NAD+, which accepts electrons and becomes reduced to NADH. This pairing of NAD+/NADH is involved in many fundamental biological processes such as generating energy in the form of ATP during cellular respiration, and serving as a critical cofactor for various enzymes that regulate cellular functions like DNA repair, gene expression, and cell death.

Maintaining optimal levels of NAD+/NADH is crucial for overall health and longevity, as it declines with age and in certain disease states. Therefore, strategies to boost NAD+ levels are being actively researched for their potential therapeutic benefits in various conditions such as aging, neurodegenerative disorders, and metabolic diseases.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

Trypsin is a proteolytic enzyme, specifically a serine protease, that is secreted by the pancreas as an inactive precursor, trypsinogen. Trypsinogen is converted into its active form, trypsin, in the small intestine by enterokinase, which is produced by the intestinal mucosa.

Trypsin plays a crucial role in digestion by cleaving proteins into smaller peptides at specific arginine and lysine residues. This enzyme helps to break down dietary proteins into amino acids, allowing for their absorption and utilization by the body. Additionally, trypsin can activate other zymogenic pancreatic enzymes, such as chymotrypsinogen and procarboxypeptidases, thereby contributing to overall protein digestion.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

Antibody affinity refers to the strength and specificity of the interaction between an antibody and its corresponding antigen at a molecular level. It is a measure of how strongly and selectively an antibody binds to its target antigen. A higher affinity indicates a more stable and specific binding, while a lower affinity suggests weaker and less specific interactions. Affinity is typically measured in terms of the dissociation constant (Kd), which describes the concentration of antigen needed to achieve half-maximal binding to an antibody. Generally, a smaller Kd value corresponds to a higher affinity, indicating a tighter and more selective bond. This parameter is crucial in the development of diagnostic and therapeutic applications, such as immunoassays and targeted therapies, where high-affinity antibodies are preferred for improved sensitivity and specificity.

Hydrogen-ion concentration, also known as pH, is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (to the base 10) of the hydrogen ion activity in a solution. The standard unit of measurement is the pH unit. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

In medical terms, hydrogen-ion concentration is important for maintaining homeostasis within the body. For example, in the stomach, a high hydrogen-ion concentration (low pH) is necessary for the digestion of food. However, in other parts of the body such as blood, a high hydrogen-ion concentration can be harmful and lead to acidosis. Conversely, a low hydrogen-ion concentration (high pH) in the blood can lead to alkalosis. Both acidosis and alkalosis can have serious consequences on various organ systems if not corrected.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

... binding pockets can be exploited for their affinity and thus be labeled. Affinity labels can be broken down into three distinct ... "Affinity labeling-a general method for labeling the active sites of antibody and enzyme molecules". Biochemistry. 1: 1031-9. ... The tag may be either a reporter such as a fluorophore or an affinity label such as biotin or an alkyne or azide for use with ... Affinity labels are a class of enzyme inhibitors that covalently bind to their target causing its inactivation. The hallmark of ...
Vinkenborg JL, Mayer G, Famulok M (September 2012). "Aptamer-based affinity labeling of proteins". Angewandte Chemie. 51 (36): ... Because the affinity of the aptamer also affects its dynamic range and limit of detection, aptamers with a lower affinity may ... Affinity chromatography also depends on the ability of the affinity reagent, such as an aptamer, to bind and release its target ... They exhibit a range of affinities (KD in the pM to μM range), with variable levels of off-target binding and are sometimes ...
Purich DL (2010). "Irreversible Enzyme Inhibition by Affinity Labelling Agents". Enzyme Kinetics: Catalysis and Control: A ... Furthermore, the affinity of the inhibitor for the free enzyme and the enzyme-substrate complex may differ.: 136-139 By ... In these cases some of these inhibitors rapidly bind to the enzyme in a low-affinity EI complex and this then undergoes a ... The Km relating to the affinity of the enzyme for the substrate should in most cases relate to potential changes in the binding ...
See LP label of Affinity release on Discogs. See copyright credits on Impulse! CD back cover on Discogs. See credits on the ... On Compact Discs issued by Charly and Affinity the concert had an extra track as opener, "How High the Moon". In 1989 MCA ... through which it also appeared on Affinity in the UK. All releases were distributed with the same front and back cover. ... finally released the album in the US on their Impulse! label, but omitting "How High the Moon" on CD as well. When Bridgewater ...
... received a PhD in chemistry from Georgia Tech in 1978; his thesis was entitled "Affinity Labeling of ... Rasnick, David William (1978). Affinity labeling of metalloendoproteases (electronic thesis or dissertation). OCLC 638449874. ...
Her 1971 dissertation was titled, Affinity labelling lysozyme with a carbene. She earned a M.P.H. from Harvard T.H. Chan School ... Ziegler, Regina Gale (1971). Affinity labelling lysozyme with a carbene (Ph.D. thesis). University of California, Berkeley. ...
It was released in 1981 on the Affinity label. The same recordings were officially released in 2021 in cooperation with the ...
Inglese J, Johnson DL, Shiau A, Smith JM, Benkovic SJ (February 1990). "Subcloning, characterization, and affinity labeling of ... Using a bromoacetyl dideazafolate affinity analog James Inglese and colleagues first identified Asp144 as an active site ...
Affinity purification Protein array TimeSTAMP protein labelling Western blotting Mahmoudi Gomari, Mohammad; Saraygord-Afshari, ... Affinity tags are appended to proteins so that they can be purified from their crude biological source using an affinity ... Affinity tags include chitin binding protein (CBP), maltose binding protein (MBP), Strep-tag and glutathione-S-transferase (GST ... "CaptureSelect C-tag Affinity Matrix - Thermo Fisher Scientific". www.thermofisher.com. Cooper, Merideth A.; Taris, Joseph E.; ...
"Label-free microscale thermophoresis discriminates sites and affinity of protein-ligand binding". Angew. Chem. Int. Ed. Engl. ... The thermophoresis of a fluorescently labeled molecule A typically differs significantly from the thermophoresis of a molecule- ... The thermophoretic movement of the fluorescently labelled molecule is measured by monitoring the fluorescence distribution F ... change of the fluorescence detected when a temperature gradient is applied and can be used to determine binding affinities. MST ...
Other labels can be used, such as affinity, photochemical or radioisotope tags. These labels are attached to the probe itself ... Probe molecules, typically labeled with a fluorescent dye, are added to the array. Any reaction between the probe and the ... All these label free detection methods are relatively new and are not yet suitable for high-throughput protein interaction ... The advantages of controlling the precise mode of surface attachment through use of an appropriate affinity tag are that the ...
Ligand conjugation is targeted to specific lysine residues via an affinity labeling mechanism. There has been a reluctance for ... The design of covalent drugs requires careful optimization of both the non-covalent binding affinity (which is reflected in Ki ... Ostrem JM, Peters U, Sos ML, Wells JA, Shokat KM (November 2013). "K-Ras(G12C) inhibitors allosterically control GTP affinity ... Smith AJ, Zhang X, Leach AG, Houk KN (January 2009). "Beyond picomolar affinities: quantitative aspects of noncovalent and ...
Ratajczak T, Sheppard PN, Capon RJ, Hähnel R (November 1981). "The synthesis and study of some potential affinity labeling ... "A comparison of 11 beta-chloromethylestradiol and tamoxifen aziridine as affinity labeling reagents for estrogen receptors". ... The relative binding affinity of 11β-CME2 for the estrogen receptors ranges from 230 to 3,320% of that of estradiol depending ... It has very high affinity for the estrogen receptor and dissociates from it relatively slowly. It was originally thought that ...
The film was distributed internationally by Sierra/Affinity, a label of Entertainment One. Orphan: First Kill was released ... The project was announced as a joint-venture production between eOne, Dark Castle Entertainment, Sierra/Affinity, and Eagle ... by Paramount Pictures through the Paramount Players label in select theatres, digital, and streaming via Paramount+. The film ...
Maryanoff BE, Simon EJ, Gioannini T, Gorissen H (August 1982). "Potential affinity labels for the opiate receptor based on ... Maryanoff BE, Simon EJ, Gioannini T, Gorissen H (August 1982). "Potential affinity labels for the opiate receptor based on ... Essawi MY (April 1999). "Fentanyl analogues with a modified propanamido group as potential affinity labels: synthesis and in ...
Uram JD, Ke K, Hunt AJ, Mayer M (March 2006). "Label-free affinity assays by rapid detection of immune complexes in ... Gao QH, Zhang WM, Zou HX, Li WB, Yan H, Peng ZK, Meng G (2019). "Label-free manipulation via the magneto-Archimedes effect: ... Other research has also shown that the label-free separation of cells may be possible by suspending cells in a paramagnetic ... Akiyama Y, Morishima K (2011-04-18). "Label-free cell aggregate formation based on the magneto-Archimedes effect". Applied ...
"Inactivation of Escherichia coli outer-membrane phospholipase A by the affinity label hexadecanesulfonyl fluoride. Evidence for ...
... a specific high affinity ligand for labeling the dopamine transport complex". European Journal of Pharmacology. 107 (2): 289-90 ... and oxo substituents on affinity for the dopamine and serotonin transporters". Journal of Medicinal Chemistry. 51 (9): 2795-806 ... 3H radiolabelled form for the purpose of mapping the distribution of dopaminergic neurons in the brain by selective labelling ...
Affinity labelling of the 40S subunits by derivatives of oligoribonucleotides containing the AUG codon". Biochim. Biophys. Acta ...
Affinity labelling of the 40S subunits by derivatives of oligoribonucleotides containing the AUG codon". Biochim. Biophys. Acta ...
Affinity labelling of the 40S subunits by derivatives of oligoribonucleotides containing the AUG codon". Biochim. Biophys. Acta ...
Isotope-coded affinity tag (ICAT), label-free) and qualitative. In collaboration with scientists at the University of Dundee, ...
"Solution-Phase vs Surface-Phase Aptamer-Protein Affinity from a Label-Free Kinetic Biosensor". PLOS ONE. 8 (9): e75419. Bibcode ... which prove to get the advantages of both label-based and label-free detection methods in the single setup. SPR imaging is used ... Affinity interactions can be studied for a variety of target molecules e.g. proteins and nucleic acids. Mismatching of bases in ... Although it's label free but will need to have crystal clean experimental conditions. Sensitivity of SPRM can be improved with ...
Affinity labelling of the 40S subunits by derivatives of oligoribonucleotides containing the AUG codon". Biochim. Biophys. Acta ...
... a high affinity ligand and novel photoaffinity labeling reagent for the progesterone receptor". J. Steroid Biochem. 35 (2): 179 ... The affinity of DU-41164 for the progesterone receptor was described in 1974 as "probably the highest reported for any steroid- ... The drug shows extremely high potency as a progestogen in animals; it was reported to possess 500 times the affinity of ... A closely related compound, DU-41165, has been developed as a photoaffinity label for the progesterone receptor. Halkes SJ, ...
As affinity probes in CAE, fluorophore-labeled compounds with affinities for the target molecules are employed. With ACE, ... The proteins that do not have affinity for the affinity probes pass through the affinity-trap gel, and proteins with affinity ... These receptor molecules often take the form of affinity probes consisting of fluorophore-labeled molecules that will bind to ... Phosphate affinity electrophoresis utilizes an affinity probe which consists of a molecule that binds specifically to divalent ...
Murale DP, Hong SC, Haque MM, Lee JS (2017-06-24). "Photo-affinity labeling (PAL) in chemical proteomics: a handy tool to ... In a label transfer reaction, a known protein is tagged with a detectable label. The label is then passed to an interacting ... Affinity electrophoresis as used for estimation of binding constants, as for instance in lectin affinity electrophoresis or ... Label transfer can also detect weak or transient interactions that are difficult to capture using other in vitro detection ...
Affinity labeling of an active site lysine by pyridoxal 5'-phosphate and pyridoxal 5'-diphospho-5'-adenosine". The Journal of ...
... for affinity chromatography, affinity labeling, affinity therapy, and the avidin-biotin system. The avidin-biotin complex is ... Specific uses of affinity chromatography include antibody affinity, Immobilized metal ion affinity chromatography and ... Strausbauch, P.H., Weinstein, Y., Wilchek, M., Shaltiel, S., Givol, D. (1971). "A homologous series of affinity labeling ... thus laying the grounds for modern hemoperfusion Affinity label is a molecule that is similar in structure to a particular ...
Affinity label for the tRNA binding sites on the E. coli ribosome allowed the identification of A and P site proteins most ... During 1977, Czernilofsky published research that used affinity labeling to identify tRNA-binding sites on rat liver ribosomes ... "The site of reaction on ribosomal protein L27 with an affinity label derivative of tRNA Met f". FEBS Letters. 63 (2): 283-6. ... likely associated with the peptidyltransferase activity; labelled proteins are L27, L14, L15, L16, L2; at least L27 is located ...
... binding pockets can be exploited for their affinity and thus be labeled. Affinity labels can be broken down into three distinct ... "Affinity labeling-a general method for labeling the active sites of antibody and enzyme molecules". Biochemistry. 1: 1031-9. ... The tag may be either a reporter such as a fluorophore or an affinity label such as biotin or an alkyne or azide for use with ... Affinity labels are a class of enzyme inhibitors that covalently bind to their target causing its inactivation. The hallmark of ...
... for the absolute quantification of proteins in complex samples based on polyclonal antibodies and stable isotope-labeled … ... Immunoproteomics using polyclonal antibodies and stable isotope-labeled affinity-purified recombinant proteins Mol Cell ... in complex samples based on polyclonal antibodies and stable isotope-labeled recombinant protein fragments to allow affinity ... The approach was further developed to also generate quantitative data via the addition of heavy isotope-labeled recombinant ...
Malvano, F., Albanese, D., Pilloton, R. et al. A New Label-Free Impedimetric Affinity Sensor Based on Cholinesterases for ... A New Label-Free Impedimetric Affinity Sensor Based on Cholinesterases for Detection of Organophosphorous and Carbamic ... Malvano, F., ese, D., Pilloton, R., & Di Matteo, M. (2016). A highly sensitive impedimetric label free immunosensor for ...
AB-N44) , affinity-purified (Cat. #AB-N44AP) , affinity-purified biotin-labeled (Cat. #AB-N44AP-BT) , affinity-purified ... Alexa488-labeled affinity-purified [AB-N44AP-FLA]. $445.00. vGAT Rabbit Polyclonal, Alexa488-labeled affinity-purified [AB- ... Be the first to review "vGAT Rabbit Polyclonal, Alexa488-labeled affinity-purified [AB-N44AP-FLA]". You must be logged in to ... Home / Products / Antibodies / vGAT Rabbit Polyclonal, Alexa488-labeled affinity-purified [AB-N44AP-FLA]. Antibodies. vGAT ...
Cy3-labeled affinity-purified [AB-N01AP-FL3]. Antibodies. NGFR (mu p75) Rabbit Polyclonal, Cy3-labeled affinity-purified [AB- ... AB-N01) , affinity-purified (Cat. #AB-N01AP) , biotin-labeled (Cat. #AB-N01AP-BT) , Cy3-labeled (Cat. #AB-N01AP-FL3) , Cy5- ... Be the first to review "NGFR (mu p75) Rabbit Polyclonal, Cy3-labeled affinity-purified [AB-N01AP-FL3]". You must be logged in ... AB-N01AP-FL5) , Alexa488-labeled (Cat. #AB-N01AP-FLA). NGFR (ME20.4, p75) Mouse Monoclonal (Cat. #AB-N07) , biotin-labeled (Cat ...
Comparison of fluorescence labelling techniques for the selection of affinity ligands from solid-phase combinatorial libraries. ... Comparison of fluorescence labelling techniques for the selection of affinity ligands from solid-phase combinatorial libraries ... Pina, AS, Lowe, CR & Roque, ACA 2010, Comparison of fluorescence labelling techniques for the selection of affinity ligands ... Comparison of fluorescence labelling techniques for the selection of affinity ligands from solid-phase combinatorial libraries ...
The antibody was affinity-purified against saporin attached to a CnBr-Sepharose support column. It has been conjugated to ... Product Size: 50 ug , Antibody Type: affinity-purified, Polyclonal , Host: Goat , Reactivity: All species , Conjugate: Biotin ...
HRP labeled Cygnus CHO HCP Ab C0016AF-HRP ... Antibody Affinity Extraction (AAE™). Mass Spectrometry & HCP ...
Affinity Creatives Sweet Wine Labels. Package Design USA (PDUSA) February 17, 2021 Ilana Greenberg ... Affinity Awakens the Spirit of Alaska. Package Design USA (PDUSA) October 6, 2020October 16, 2020 Ilana Greenberg ... Bringing Nobility To Wine Labels. Package Design USA (PDUSA), Top Stories November 30, 2020December 7, 2020 Ilana Greenberg ... Affinity, a creative agency for wine, spirits, and other luxury products, reimagines Anchorage Distillerys offering and re- ...
... ... Furthermore, the photo-affinity labeling technique described here can be readily applied to other drugs of unknown targets to ... Photo-affinity labelling and biochemical analyses identify the target of trypanocidal simplified natural product analogues , ... Bi-functional compound 3 was UV cross-linked to its target(s) in vivo and biotin affinity or Cy5.5 reporter tags were ...
Kuwahara, D., Hasumi, T., Kaneko, H., Unno, M., Takahashi, D., & Toshima, K. (2014). A solid-phase affinity labeling method for ... Kuwahara, D, Hasumi, T, Kaneko, H, Unno, M, Takahashi, D & Toshima, K 2014, A solid-phase affinity labeling method for target- ... A solid-phase affinity labeling method for target-selective isolation and modification of proteins. In: Chemical Communications ... A solid-phase affinity labeling method for target-selective isolation and modification of proteins. Chemical Communications. ...
... the proteome reactivity using chemical probescontaining thiol-reactive functional groups and discovered a unique labeling ... Photo-affinity labeling (PAL) in chemical proteomics: a handy tool to investigate protein-protein interactions (PPIs) *Dhiraj P ... Flu-IA was administered to livecells: either "light" isotope-labeled APC140 cells or"heavy" isotope-labeled Huh7.5 cells at a1 ... Then, cells that were not treatedwith Flu-IA were prepared as a control and the lysates were also labeled with excessBiotin-IA ...
Label Based Affinity. While Red Hat Virtualization already has the ability to set host based affinity/anti-affinity, the ... The label functionality enables the administrator to configure one virtual machines affinity, then create an affinity label ... Label based affinity is a way of streamlining administration and configuration time. There are many ways that label based ... The remaining virtual machines are easily configured by simply applying that same affinity label. This is much faster as ...
Technology enables covalent protein labeling and immobilization in vivo and in vitro. ... Covalently Attach Fluorescent Labels or Affinity Tags to Membrane or Intracellular Proteins. *Cell permeant TMR, Oregon Green ... Ligands with a variety of functionalities, including fluorescent labels, affinity tags and solid phase attachment abilities. ... Analyze Labeled Fusion Proteins Using SDS-PAGE, Mass Spectrometry, etc.: The bound ligand is stable under denaturing conditions ...
Affinity labeling of hepatitis C virus replicase with a nucleotide analogue: Identification of binding site. Read our blog ...
We transcribed and analyzed interviews according to thematic analysis and an affinity diagramming process. Results: Providers ... Affinity diagram labels.. PDF File (Adobe PDF File), 46KB. References. *Fox S, Duggan M. Pew Research Center. Washington, DC: ... In addition to our affinity analysis, we coded each transcript through a mix of deductive (based on our research questions and ... The full research team conducted an affinity diagram analysis [45] to identify key themes. We transformed the interview ...
Alkyne Labeled Affinity and Purification Reagents - Functionalized agarose - Alkyne Labeled - VectorLabs ... Affinity and Purification Reagents *Functionalized Magnetic beads. *Functionalized Agarose. *Streptavidin-Free Protein ...
Antibody labelling (7). * Target binding affinity (7). * IHC-P (6). * ICC/IF (5). ...
KPL Biotin-Labeled Affinity Purified Antibody to Human IgM (µ). Doc type ... Affinity purified polyclonal antibody to human IgM heavy chains (mu) made in goat and biotinylated. Product is in lyophilized ...
... a quantitative quality control method that evaluates binding affinity post-conjugation and efficiency of antibody labeling. ... Validated in Target binding affinity, Antibody labelling. ... Suitable for: Antibody labelling, Target binding affinitymore ...
"Irreversible Enzyme Inhibition by Affinity Labelling Agents". Enzyme Kinetics: Catalysis and Control: A Reference of Theory and ... Non-competitive inhibitors have identical affinities for E and ES (Ki = Ki). Non-competitive inhibition does not change Km (i. ... Mixed-type inhibitors bind to both E and ES, but their affinities for these two forms of the enzyme are different (Ki ≠ Ki). ... The Km relating to the affinity of the enzyme for the substrate should in most cases relate to potential changes in the binding ...
PDB Description: Pikromycin Thioesterase with covalent affinity label. PDB Compounds: (A:) Type I polyketide synthase PikAIV. ...
I have always had an affinity for crate labels.. What was once the ubiquitous wooden (fruit) crate is now the cardboard or ... Produce crate labels. Posted on. Wednesday, February 8, 2012. Wednesday, February 8, 2012. AuthorCharley Parker6 Comments ... Google fruit crate labels and most of the reputable US dealers will come up on top, its worth a browse of their sites just ... Product can labels are also great and can be very evocative of their periods. Dover has a couple of collections available in ...
Label-Free Microscale Thermophoresis Discriminates Sites and Affinity of Protein-Ligand Binding. Angew. Chem. Int. Edit. 2012, ... STV is known for its extremely high binding affinity to biotin, with the dissociation constant in the range of K. d. ≈. 4. ×. ... Either a fluorescent label is attached or the inherent fluorescence of the molecule of interest is detected [24]. While these ... It turns out that the hydrophilicity of the solute (or hydrophobicity, if the affinity is small) plays an important role in the ...
For advances in protein structure and enzyme mechanisms by use of affinity labeling and site-directed mutagenesis. ...
Journal Article] Traceless Affinity Labeling of Endogenous Proteins for Functional Analysis in Living Cells2012. *. Author(s). ... Presentation] Selective Chemical Labeling and Engineering of Endogenous Proteins in Test Tube, in Cell and in Vivo2010. *. ... Presentation] Selective Chemical Labeling and Imaging of Endogenous Protein in Live Cells2013. *. Author(s). Itaru Hamachi ... Journal Article] Site-Specific Covalent Labeling of His-tag Fused Proteins with a Reactive Ni(II)-NTA Probe2009. *. Author(s). ...
Isotope Coded Affinity Tags (ICAT): See under differential labeling. in situ hybridization ISH: Gene amplification & PCR. ... target labelling Related terms: assays, dyes, reagents, staining and labeling, target labelling, tracer; Ultrasensitivity label ... primed in situ labeling: A technique that labels specific sequences in whole chromosomes by in situ DNA chain elongation or PCR ... tag: See label, capture tag, Isotope Coded Affinity Tags ICAT, optical tagging. This is different from tagging for information ...
Label-Free Microscale Thermophoresis Discriminates Sites and Affinity of Protein-Ligand Binding. ... Look, no label! Microscale thermophoresis makes use of the intrinsic fluorescence of proteins to quantify the binding ... In vitro Percutaneous Absorption of 14C-Labeled β-Lactone Promises Topical Delivery of New Bacterial Virulence Inhibitors ... with a 100-fold higher binding affinity to the chemokine receptor CXCR4 in the ... ...

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