Inhibitors of SERINE ENDOPEPTIDASES and sulfhydryl group-containing enzymes. They act as alkylating agents and are known to interfere in the translation process.
An inhibitor of SERINE ENDOPEPTIDASES. Acts as an alkylating agent and is known to interfere with the translation process.
An inhibitor of Serine Endopeptidases. Acts as alkylating agent and is known to interfere with the translation process.
'Ketones' are organic compounds with a specific structure, characterized by a carbonyl group (a carbon double-bonded to an oxygen atom) and two carbon atoms, formed as byproducts when the body breaks down fats for energy due to lack of glucose, often seen in diabetes and starvation states.
A substance that is an irritant to the eyes and respiratory tract and may be carcinogenic.
Compounds which inhibit or antagonize biosynthesis or actions of proteases (ENDOPEPTIDASES).
Exogenous or endogenous compounds which inhibit SERINE ENDOPEPTIDASES.
The metabolic substances ACETONE; 3-HYDROXYBUTYRIC ACID; and acetoacetic acid (ACETOACETATES). They are produced in the liver and kidney during FATTY ACIDS oxidation and used as a source of energy by the heart, muscle and brain.
A di-isopropyl-fluorophosphate which is an irreversible cholinesterase inhibitor used to investigate the NERVOUS SYSTEM.
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.
Chemical compounds derived from acids by the elimination of a molecule of water.
Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.
A very strong halogenated derivative of acetic acid. It is used in acid catalyzed reactions, especially those where an ester is cleaved in peptide synthesis.
Compounds that contain a 1-dimethylaminonaphthalene-5-sulfonyl group.
Derivatives of acetic acid with one or more fluorines attached. They are almost odorless, difficult to detect chemically, and very stable. The acid itself, as well as the derivatives that are broken down in the body to the acid, are highly toxic substances, behaving as convulsant poisons with a delayed action. (From Miall's Dictionary of Chemistry, 5th ed)
Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.
The rate dynamics in chemical or physical systems.
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.
An enzyme that catalyzes the release of a N-terminal pyroglutamyl group from a polypeptide provided the next residue is not proline. It is inhibited by thiol-blocking reagents and occurs in mammalian tissues, microorganisms, and plants. (From Enzyme Nomenclature, 1992) EC 3.4.19.3.
A protease of broad specificity, obtained from dried pancreas. Molecular weight is approximately 25,000. The enzyme breaks down elastin, the specific protein of elastic fibers, and digests other proteins such as fibrin, hemoglobin, and albumin. EC 3.4.21.36.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.
An organic mercurial used as a sulfhydryl reagent.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The sum of the weight of all the atoms in a molecule.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A serine endopeptidase secreted by the pancreas as its zymogen, CHYMOTRYPSINOGEN and carried in the pancreatic juice to the duodenum where it is activated by TRYPSIN. It selectively cleaves aromatic amino acids on the carboxyl side.
Tosyl compounds are organic derivatives characterized by the introduction of a tosyl group, which is the sulfonate ester of p-toluenesulfonic acid (CH3C6H4SO3H), into an organic molecule through a substitution reaction.
Serine proteinase inhibitors which inhibit trypsin. They may be endogenous or exogenous compounds.
ENDOPEPTIDASES which have a cysteine involved in the catalytic process. This group of enzymes is inactivated by CYSTEINE PROTEINASE INHIBITORS such as CYSTATINS and SULFHYDRYL REAGENTS.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A genus of microorganisms of the order SPIROCHAETALES, many of which are pathogenic and parasitic for man and animals.
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)
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.
The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.
A group of acylated oligopeptides produced by Actinomycetes that function as protease inhibitors. They have been known to inhibit to varying degrees trypsin, plasmin, KALLIKREINS, papain and the cathepsins.
An enzyme inhibitor that inactivates IRC-50 arvin, subtilisin, and the fatty acid synthetase complex.
Physiologically inactive substances that can be converted to active enzymes.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
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 enzyme formed from PROTHROMBIN that converts FIBRINOGEN to FIBRIN.
A species of gram-negative, anaerobic, rod-shaped bacteria originally classified within the BACTEROIDES genus. This bacterium produces a cell-bound, oxygen-sensitive collagenase and is isolated from the human mouth.
The process of cleaving a chemical compound by the addition of a molecule of water.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
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.
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.
Established cell cultures that have the potential to propagate indefinitely.
Exogenous and endogenous compounds which inhibit CYSTEINE ENDOPEPTIDASES.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
Peptides composed of between two and twelve amino acids.
Antibiotic substance isolated from streptomycin-producing strains of Streptomyces griseus. It acts by inhibiting elongation during protein synthesis.
A genus of gram-negative, anaerobic, rod-shaped bacteria. Its organisms are normal inhabitants of the oral, respiratory, intestinal, and urogenital cavities of humans, animals, and insects. Some species may be pathogenic.
Ubiquitous, inducible, nuclear transcriptional activator that binds to enhancer elements in many different cell types and is activated by pathogenic stimuli. The NF-kappa B complex is a heterodimer composed of two DNA-binding subunits: NF-kappa B1 and relA.
Protein precursors, also known as proproteins or prohormones, are inactive forms of proteins that undergo post-translational modification, such as cleavage, to produce the active functional protein or peptide hormone.
Amino acids that are not synthesized by the human body in amounts sufficient to carry out physiological functions. They are obtained from dietary foodstuffs.
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.
An industrial solvent which causes nervous system degeneration. MBK is an acronym often used to refer to it.
Cellular proteins and protein complexes that transport amino acids across biological membranes.
Salts and derivatives of acetoacetic acid.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
BUTYRIC ACID substituted in the beta or 3 position. It is one of the ketone bodies produced in the liver.
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Commonly observed structural components of proteins formed by simple combinations of adjacent secondary structures. A commonly observed structure may be composed of a CONSERVED SEQUENCE which can be represented by a CONSENSUS SEQUENCE.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
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.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.

Activation of stress-activated protein kinase/c-Jun NH2-terminal kinase and p38 kinase in calphostin C-induced apoptosis requires caspase-3-like proteases but is dispensable for cell death. (1/1161)

Apoptosis was induced in human glioma cell lines by exposure to 100 nM calphostin C, a specific inhibitor of protein kinase C. Calphostin C-induced apoptosis was associated with synchronous down-regulation of Bcl-2 and Bcl-xL as well as activation of caspase-3 but not caspase-1. The exposure to calphostin C led to activation of stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK) and p38 kinase and concurrent inhibition of extracellular signal-regulated kinase (ERK). Upstream of ERK, Shc was shown to be activated, but its downstream Raf1 and ERK were inhibited. The pretreatment with acetyl-Tyr-Val-Ala-Asp-aldehyde, a relatively selective inhibitor of caspase-3, or benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD.fmk), a broad spectrum caspase inhibitor, similarly inhibited calphostin C-induced activation of SAPK/JNK and p38 kinase as well as apoptotic nuclear damages (chromatin condensation and DNA fragmentation) and cell shrinkage, suggesting that caspase-3 functions upstream of SAPK/JNK and p38 kinase, but did not block calphostin C-induced surface blebbing and cell death. On the other hand, the inhibition of SAPK/JNK by transfection of dominant negative SAPK/JNK and that of p38 kinase by SB203580 induced similar effects on the calphostin C-induced apoptotic phenotypes and cell death as did z-VAD.fmk and acetyl-Tyr-Val-Ala-Asp-aldehyde, but the calphostin C-induced PARP cleavage was not changed, suggesting that SAPK/JNK and p38 kinase are involved in the DNA fragmentation pathway downstream of caspase-3. The present findings suggest, therefore, that the activation of SAPK/JNK and p38 kinase is dispensable for calphostin C-mediated and z-VAD.fmk-resistant cell death.  (+info)

Role of hypoxia-induced Bax translocation and cytochrome c release in reoxygenation injury. (2/1161)

We investigated mechanisms of cell death during hypoxia/reoxygenation of cultured kidney cells. During glucose-free hypoxia, cell ATP levels declined steeply resulting in the translocation of Bax from cytosol to mitochondria. Concurrently, there was cytochrome c release and caspase activation. Cells that leaked cytochrome c underwent apoptosis after reoxygenation. ATP depletion induced by a mitochondrial uncoupler resulted in similar alterations even in the presence of oxygen. Moreover, inclusion of glucose during hypoxia prevented protein translocations and reoxygenation injury by maintaining intracellular ATP. Thus, ATP depletion, rather than hypoxia per se, was the cause of protein translocations. Overexpression of Bcl-2 prevented cytochrome c release and reoxygenation injury without ameliorating ATP depletion or Bax translocation. On the other hand, caspase inhibitors did not prevent protein translocations, but inhibited apoptosis during reoxygenation. Nevertheless, they could not confer long-term viability, since mitochondria had been damaged. Omission of glucose during reoxygenation resulted in continued failure of ATP production, and cell death with necrotic morphology. In contrast, cells expressing Bcl-2 had functional mitochondria and remained viable during reoxygenation even without glucose. Therefore, Bax translocation during hypoxia is a molecular trigger for cell death during reoxygenation. If ATP is available during reoxygenation, apoptosis develops; otherwise, death occurs by necrosis. By preserving mitochondrial integrity, BCL-2 prevents both forms of cell death and ensures cell viability.  (+info)

Anti-apoptotic role of telomerase in pheochromocytoma cells. (3/1161)

Telomerase is a protein-RNA enzyme complex that adds a six-base DNA sequence (TTAGGG) to the ends of chromosomes and thereby prevents their shortening. Reduced telomerase activity is associated with cell differentiation and accelerated cellular senescence, whereas increased telomerase activity is associated with cell transformation and immortalization. Because many types of cancer have been associated with reduced apoptosis, whereas cell differentiation and senescence have been associated with increased apoptosis, we tested the hypothesis that telomerase activity is mechanistically involved in the regulation of apoptosis. Levels of telomerase activity in cultured pheochromocytoma cells decreased prior to cell death in cells undergoing apoptosis. Treatment of cells with the oligodeoxynucleotide TTAGGG or with 3,3'-diethyloxadicarbocyanine, agents that inhibit telomerase activity in a concentration-dependent manner, significantly enhanced mitochondrial dysfunction and apoptosis induced by staurosporine, Fe2+ (an oxidative insult), and amyloid beta-peptide (a cytotoxic peptide linked to neuronal apoptosis in Alzheimer's disease). Overexpression of Bcl-2 and the caspase inhibitor zVAD-fmk protected cells against apoptosis in the presence of telomerase inhibitors, suggesting a site of action of telomerase prior to caspase activation and mitochondrial dysfunction. Telomerase activity decreased in cells during the process of nerve growth factor-induced differentiation, and such differentiated cells exhibited increased sensitivity to apoptosis. Our data establish a role for telomerase in suppressing apoptotic signaling cascades and suggest a mechanism whereby telomerase may suppress cellular senescence and promote tumor formation.  (+info)

Monocytic cell necrosis is mediated by potassium depletion and caspase-like proteases. (4/1161)

Apoptosis is a physiological cell death that culminates in mitochondrial permeability transition and the activation of caspases, a family of cysteine proteases. Necrosis, in contrast, is a pathological cell death characterized by swelling of the cytoplasm and mitochondria and rapid plasma membrane disruption. Necrotic cell death has long been opposed to apoptosis, but it now appears that both pathways involve mitochondrial permeability transition, raising the question of what mediates necrotic cell death. In this study, we investigated mechanisms that promote necrosis induced by various stimuli (Clostridium difficile toxins, Staphylococcus aureus alpha toxin, ouabain, nigericin) in THP-1 cells, a human monocytic cell line, and in monocytes. All stimuli induced typical features of necrosis and triggered protease-mediated release of interleukin-1beta (IL-1beta) and CD14 in both cell types. K+ depletion was actively implicated in necrosis because substituting K+ for Na+ in the extracellular medium prevented morphological features of necrosis and IL-1beta release. N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone, a broad-spectrum caspase inhibitor, prevented morphological features of necrosis, plasma membrane destruction, loss of mitochondrial membrane potential, IL-1beta release, and CD14 shedding induced by all stimuli. Thus, in monocytic cells, necrosis is a cell death pathway mediated by passive K+ efflux and activation of caspase-like proteases.  (+info)

Identification of megalin/gp330 as a receptor for lipoprotein(a) in vitro. (5/1161)

Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein of unknown physiological function. The mechanism of Lp(a) atherogenicity as well as its catabolic pathways are only incompletely understood at present. In this report, we show that the low density lipoprotein receptor (LDLR) gene family member megalin/glycoprotein (gp) 330 is capable of binding and mediating the cellular uptake and degradation of Lp(a) in vitro. A mouse embryonic yolk sac cell line with native expression of megalin/gp330 but genetically deficient in LDLR-related protein (LRP) and a control cell line carrying a double knockout for both LRP and megalin/gp330 were compared with regard to their ability to bind, internalize, and degrade dioctadecyltetramethylindocarbocyanine perchlorate (DiI)-fluorescence-labeled Lp(a) as well as equimolar amounts of 125I-labeled Lp(a) and LDL. Uptake and degradation of radiolabeled Lp(a) by the megalin/gp330-expressing cells were, on average, 2-fold higher than that of control cells. This difference could be completely abolished by addition of the receptor-associated protein, an inhibitor of ligand binding to megalin/gp330. Mutual suppression of the uptake of 125I-Lp(a) and of 125I-LDL by both unlabeled Lp(a) and LDL suggested that Lp(a) uptake is mediated at least partially by apolipoprotein B100. Binding and uptake of DiI-Lp(a) resulted in strong signals on megalin/gp330-expressing cells versus background only on control cells. In addition, we show that purified megalin/gp330, immobilized on a sensor chip, directly binds Lp(a) in a Ca2+-dependent manner with an affinity similar to that for LDL. We conclude that megalin/gp330 binds Lp(a) in vitro and is capable of mediating its cellular uptake and degradation.  (+info)

Caspase-dependent activation of calpain during drug-induced apoptosis. (6/1161)

We have previously demonstrated that calpain is responsible for the cleavage of Bax, a proapoptotic protein, during drug-induced apoptosis of HL-60 cells (Wood, D. E., Thomas, A., Devi, L. A., Berman, Y., Beavis, R. C., Reed, J. C., and Newcomb, E. W. (1998) Oncogene 17, 1069-1078). Here we show the sequential activation of caspases and calpain during drug-induced apoptosis of HL-60 cells. Time course experiments using the topoisomerase I inhibitor 9-amino-20(S)-camptothecin revealed that cleavage of caspase-3 substrates poly(ADP-ribose) polymerase (PARP) and the retinoblastoma protein as well as DNA fragmentation occurred several hours before calpain activation and Bax cleavage. Pretreatment with the calpain inhibitor calpeptin blocked calpain activation and Bax cleavage but did not inhibit PARP cleavage, DNA fragmentation, or 9-amino-20(S)-camptothecin-induced morphological changes and cell death. Pretreatment with the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-fmk) inhibited PARP cleavage, DNA fragmentation, calpain activation, and Bax cleavage and increased cell survival by 40%. Interestingly, Z-VAD-fmk-treated cells died in a caspase- and calpain-independent manner that appeared morphologically distinct from apoptosis. Our results suggest that excessive or uncontrolled calpain activity may play a role downstream of and distinct from caspases in the degradation phase of apoptosis.  (+info)

Essential role of caspase-3 in apoptosis of mouse beta-cells transfected with human Fas. (7/1161)

Several recent studies have indicated that the Fas-Fas ligand system may be critical for pancreatic beta-cell destruction in type 1 diabetes. Although the fundamental roles of caspases in the mammalian apoptotic machinery have been elucidated, it is not known which caspase or caspases play a major role in Fas-mediated apoptosis of beta-cells. In this study, we transfected human Fas cDNA into a mouse beta-cell line (betaTC1) and established a beta-cell clone expressing human Fas. This clone, designated hFas/betaTC1, underwent apoptosis when exposed to anti-Fas, showing hallmarks of apoptosis (chromatin condensation, nucleolar disintegration, internucleosomal DNA fragmentation, and annexin V staining), indicating that the mouse beta-cell line has the intact machinery of Fas-mediated apoptosis. The cross-linking of Fas by anti-Fas resulted in the elevation of caspase-3-like, but not caspase-1-like, protease activity 2-12 h after the addition of the anti-Fas. A caspase-3 inhibitor, Z-Asp-Glu-Val-Asp-fluoromethyl ketone, attenuated the Fas-mediated beta-cell apoptosis, while a caspase-1 inhibitor, acetyl-Tyr-Val-Ala-Asp-chloromethylketone, failed to suppress the apoptosis. Thus the Fas-induced death signal apparently bypassed caspase-1 in the cells. Furthermore, an antisense caspase-3 construct blocked caspase-3 activation and substantially suppressed Fas-triggered apoptosis of hFas/betaTC1 cells. These observations suggest the essential role of caspase-3 in Fas-mediated apoptosis of the beta-cell line.  (+info)

The release of cytochrome c from mitochondria during apoptosis of NGF-deprived sympathetic neurons is a reversible event. (8/1161)

During apoptosis induced by various stimuli, cytochrome c is released from mitochondria into the cytosol where it participates in caspase activation. This process has been proposed to be an irreversible consequence of mitochondrial permeability transition pore opening, which leads to mitochondrial swelling and rupture of the outer mitochondrial membrane. Here we present data demonstrating that NGF-deprived sympathetic neurons protected from apoptosis by caspase inhibitors possess mitochondria which, though depleted of cytochrome c and reduced in size, remained structurally intact as viewed by electron microscopy. After re-exposure of neurons to NGF, mitochondria recovered their normal size and their cytochrome c content, by a process requiring de novo protein synthesis. Altogether, these data suggest that depletion of cytochrome c from mitochondria is a controlled process compatible with function recovery. The ability of sympathetic neurons to recover fully from trophic factor deprivation provided irreversible caspase inhibitors have been present during the insult period, has therapeutical implications for a number of acute neuropathologies.  (+info)

Amino acid chloromethyl ketones (AACMKs) are a class of chemical compounds that are widely used in research and industry. They are derivatives of amino acids, which are the building blocks of proteins, with a chloromethyl ketone group (-CO-CH2Cl) attached to the side chain of the amino acid.

In the context of medical research, AACMKs are often used as irreversible inhibitors of enzymes, particularly those that contain active site serine or cysteine residues. The chloromethyl ketone group reacts with these residues to form a covalent bond, which permanently inactivates the enzyme. This makes AACMKs useful tools for studying the mechanisms of enzymes and for developing drugs that target specific enzymes.

However, it is important to note that AACMKs can also be highly reactive and toxic, and they must be handled with care in the laboratory. They have been shown to inhibit a wide range of enzymes, including some that are essential for normal cellular function, and prolonged exposure can lead to cell damage or death. Therefore, their use is typically restricted to controlled experimental settings.

Tosyllysine Chloromethyl Ketone (TLCK) is not a medical term, but a chemical compound used in biochemical research. It is often used as an irreversible inhibitor of serine proteases, a type of enzyme that cuts other proteins. TLCK modifies the active site of these enzymes, rendering them inactive. This property makes it useful in studying the role of specific proteases in various biological processes.

Tosylphenylalanyl Chloromethyl Ketone (TPCK) is not a medical term per se, but it is a chemical compound that has been used in medical research. Here's the definition of this compound:

Tosylphenylalanyl Chloromethyl Ketone is a synthetic chemical compound with the formula C14H12ClNO3S. It is a white crystalline powder that is soluble in organic solvents and has a molecular weight of 307.75 g/mol.

TPCK is an irreversible inhibitor of serine proteases, which are enzymes that cut other proteins at specific amino acid sequences. TPCK works by reacting with the active site of these enzymes and forming a covalent bond, thereby blocking their activity. It has been used in research to study the role of serine proteases in various biological processes, including inflammation, blood coagulation, and cancer.

It is important to note that TPCK is highly toxic and should be handled with appropriate safety precautions, including the use of personal protective equipment (PPE) such as gloves and lab coats, and proper disposal in accordance with local regulations.

Ketones are organic compounds that contain a carbon atom bound to two oxygen atoms and a central carbon atom bonded to two additional carbon groups through single bonds. In the context of human physiology, ketones are primarily produced as byproducts when the body breaks down fat for energy in a process called ketosis.

Specifically, under conditions of low carbohydrate availability or prolonged fasting, the liver converts fatty acids into ketone bodies, which can then be used as an alternative fuel source for the brain and other organs. The three main types of ketones produced in the human body are acetoacetate, beta-hydroxybutyrate, and acetone.

Elevated levels of ketones in the blood, known as ketonemia, can occur in various medical conditions such as diabetes, starvation, alcoholism, and high-fat/low-carbohydrate diets. While moderate levels of ketosis are generally considered safe, severe ketosis can lead to a life-threatening condition called diabetic ketoacidosis (DKA) in people with diabetes.

Protease inhibitors are a class of antiviral drugs that are used to treat infections caused by retroviruses, such as the human immunodeficiency virus (HIV), which is responsible for causing AIDS. These drugs work by blocking the activity of protease enzymes, which are necessary for the replication and multiplication of the virus within infected cells.

Protease enzymes play a crucial role in the life cycle of retroviruses by cleaving viral polyproteins into functional units that are required for the assembly of new viral particles. By inhibiting the activity of these enzymes, protease inhibitors prevent the virus from replicating and spreading to other cells, thereby slowing down the progression of the infection.

Protease inhibitors are often used in combination with other antiretroviral drugs as part of highly active antiretroviral therapy (HAART) for the treatment of HIV/AIDS. Common examples of protease inhibitors include saquinavir, ritonavir, indinavir, and atazanavir. While these drugs have been successful in improving the outcomes of people living with HIV/AIDS, they can also cause side effects such as nausea, diarrhea, headaches, and lipodystrophy (changes in body fat distribution).

Serine proteinase inhibitors, also known as serine protease inhibitors or serpins, are a group of proteins that inhibit serine proteases, which are enzymes that cut other proteins in a process called proteolysis. Serine proteinases are important in many biological processes such as blood coagulation, fibrinolysis, inflammation and cell death. The inhibition of these enzymes by serpin proteins is an essential regulatory mechanism to maintain the balance and prevent uncontrolled proteolytic activity that can lead to diseases.

Serpins work by forming a covalent complex with their target serine proteinases, irreversibly inactivating them. The active site of serpins contains a reactive center loop (RCL) that mimics the protease's target protein sequence and acts as a bait for the enzyme. When the protease cleaves the RCL, it gets trapped within the serpin structure, leading to its inactivation.

Serpin proteinase inhibitors play crucial roles in various physiological processes, including:

1. Blood coagulation and fibrinolysis regulation: Serpins such as antithrombin, heparin cofactor II, and protease nexin-2 control the activity of enzymes involved in blood clotting and dissolution to prevent excessive or insufficient clot formation.
2. Inflammation modulation: Serpins like α1-antitrypsin, α2-macroglobulin, and C1 inhibitor regulate the activity of proteases released during inflammation, protecting tissues from damage.
3. Cell death regulation: Some serpins, such as PI-9/SERPINB9, control apoptosis (programmed cell death) by inhibiting granzyme B, a protease involved in this process.
4. Embryonic development and tissue remodeling: Serpins like plasminogen activator inhibitor-1 (PAI-1) and PAI-2 regulate the activity of enzymes involved in extracellular matrix degradation during embryonic development and tissue remodeling.
5. Neuroprotection: Serpins such as neuroserpin protect neurons from damage by inhibiting proteases released during neuroinflammation or neurodegenerative diseases.

Dysregulation of serpins has been implicated in various pathological conditions, including thrombosis, emphysema, Alzheimer's disease, and cancer. Understanding the roles of serpins in these processes may provide insights into potential therapeutic strategies for treating these diseases.

Ketone bodies, also known as ketones or ketoacids, are organic compounds that are produced by the liver during the metabolism of fats when carbohydrate intake is low. They include acetoacetate (AcAc), beta-hydroxybutyrate (BHB), and acetone. These molecules serve as an alternative energy source for the body, particularly for the brain and heart, when glucose levels are insufficient to meet energy demands.

In a healthy individual, ketone bodies are present in low concentrations; however, during periods of fasting, starvation, or intense physical exertion, ketone production increases significantly. In some pathological conditions like uncontrolled diabetes mellitus, the body may produce excessive amounts of ketones, leading to a dangerous metabolic state called diabetic ketoacidosis (DKA).

Elevated levels of ketone bodies can be detected in blood or urine and are often used as an indicator of metabolic status. Monitoring ketone levels is essential for managing certain medical conditions, such as diabetes, where maintaining optimal ketone concentrations is crucial to prevent complications.

I'm sorry for any confusion, but "Isoflurophate" does not appear to be a recognized term in medical or scientific literature. It is possible that there may be a spelling error or typo in the term you are looking for. If you meant "Isoflurane," which is a commonly used anesthetic in medical and surgical procedures, I can provide a definition for that.

Isoflurane: A volatile halogenated ether liquid used as an inhalational general anesthetic agent. It has a rapid onset and offset of action, making it useful for both induction and maintenance of anesthesia. Isoflurane is also known to have bronchodilatory properties, which can be beneficial in patients with reactive airway disease or asthma.

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).

Anhydrides are chemical compounds that form when a single molecule of water is removed from an acid, resulting in the formation of a new compound. The term "anhydride" comes from the Greek words "an," meaning without, and "hydor," meaning water.

In organic chemistry, anhydrides are commonly formed by the removal of water from a carboxylic acid. For example, when acetic acid (CH3COOH) loses a molecule of water, it forms acetic anhydride (CH3CO)2O. Acetic anhydride is a reactive compound that can be used to introduce an acetyl group (-COCH3) into other organic compounds.

Inorganic anhydrides are also important in chemistry and include compounds such as sulfur trioxide (SO3), which is an anhydride of sulfuric acid (H2SO4). Sulfur trioxide can react with water to form sulfuric acid, making it a key intermediate in the production of this important industrial chemical.

It's worth noting that some anhydrides can be hazardous and may require special handling and safety precautions.

Peptide hydrolases, also known as proteases or peptidases, are a group of enzymes that catalyze the hydrolysis of peptide bonds in proteins and peptides. They play a crucial role in various biological processes such as protein degradation, digestion, cell signaling, and regulation of various physiological functions. Based on their catalytic mechanism and the specificity for the peptide bond, they are classified into several types, including serine proteases, cysteine proteases, aspartic proteases, and metalloproteases. These enzymes have important clinical applications in the diagnosis and treatment of various diseases, such as cancer, viral infections, and inflammatory disorders.

Trifluoroacetic acid (TFA) is not typically considered a medical term, but rather a chemical one. However, it does have relevance to the medical field in certain contexts, such as in laboratory settings or pharmaceutical manufacturing. Here's a definition of TFA:

Trifluoroacetic acid (C2HF3O2) is an inorganic compound that is a colorless liquid at room temperature. It has a strong, pungent odor and is highly corrosive. In the chemical industry, it is commonly used as a reagent or solvent due to its ability to dissolve a wide range of organic compounds.

In the medical field, TFA may be encountered in laboratory settings where it can be used for various purposes such as peptide synthesis, chromatography, and other chemical reactions. It is also sometimes used as an ingredient in certain pharmaceutical formulations, although its use is generally limited due to its potential toxicity.

It's worth noting that TFA is not a medication or drug, but rather a chemical compound with various industrial and laboratory applications.

Dansyl compounds are fluorescent compounds that contain a dansyl group, which is a chemical group made up of a sulfonated derivative of dimethylaminonaphthalene. These compounds are often used as tracers in biochemical and medical research because they emit bright fluorescence when excited by ultraviolet or visible light. This property makes them useful for detecting and quantifying various biological molecules, such as amino acids, peptides, and proteins, in a variety of assays and techniques, including high-performance liquid chromatography (HPLC), thin-layer chromatography (TLC), and fluorescence microscopy.

The dansyl group can be attached to biological molecules through chemical reactions that involve the formation of covalent bonds between the sulfonate group in the dansyl compound and amino, thiol, or hydroxyl groups in the target molecule. The resulting dansylated molecules can then be detected and analyzed using various techniques.

Dansyl compounds are known for their high sensitivity, stability, and versatility, making them valuable tools in a wide range of research applications. However, it is important to note that the use of dansyl compounds requires careful handling and appropriate safety precautions, as they can be hazardous if mishandled or ingested.

Fluoroacetates are organic compounds that contain a fluorine atom and an acetic acid group. The most well-known and notorious compound in this family is sodium fluoroacetate, also known as 1080 or compound 1080, which is a potent metabolic poison. It works by interfering with the citric acid cycle, a critical process that generates energy in cells. Specifically, fluoroacetates are converted into fluorocitrate, which inhibits an enzyme called aconitase, leading to disruption of cellular metabolism and ultimately cell death.

Fluoroacetates have been used as rodenticides and pesticides, but their use is highly regulated due to their high toxicity to non-target species, including humans. Exposure to fluoroacetates can cause a range of symptoms, including nausea, vomiting, seizures, and cardiac arrest, and can be fatal if not treated promptly.

Serine endopeptidases are a type of enzymes that cleave peptide bonds within proteins (endopeptidases) and utilize serine as the nucleophilic amino acid in their active site for catalysis. These enzymes play crucial roles in various biological processes, including digestion, blood coagulation, and programmed cell death (apoptosis). Examples of serine endopeptidases include trypsin, chymotrypsin, thrombin, and elastase.

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.

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.

Pyroglutamyl-Peptidase I, also known as glutaminyl cyclotransferase or QC, is an enzyme that plays a role in the post-translational modification of proteins. Specifically, it catalyzes the formation of pyroglutamate at the N-terminus of proteins and peptides that have a glutamine or glutamic acid residue in the second position. Pyroglutamate is a cyclic amide formed from the γ-carboxyl group of glutamate or the ε-amino group of glutamine, which can protect the N-terminus from degradation and affect the function, stability, and antigenicity of proteins. Pyroglutamyl-Peptidase I is widely distributed in various tissues and organisms, including humans, and has been implicated in several physiological and pathological processes, such as protein metabolism, neurodegeneration, and cancer.

Pancreatic elastase is a type of elastase that is specifically produced by the pancreas. It is an enzyme that helps in digesting proteins found in the food we eat. Pancreatic elastase breaks down elastin, a protein that provides elasticity to tissues and organs in the body.

In clinical practice, pancreatic elastase is often measured in stool samples as a diagnostic tool to assess exocrine pancreatic function. Low levels of pancreatic elastase in stool may indicate malabsorption or exocrine pancreatic insufficiency, which can be caused by various conditions such as chronic pancreatitis, cystic fibrosis, or pancreatic cancer.

Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.

Endopeptidases are a type of enzyme that breaks down proteins by cleaving peptide bonds inside the polypeptide chain. They are also known as proteinases or endoproteinases. These enzymes work within the interior of the protein molecule, cutting it at specific points along its length, as opposed to exopeptidases, which remove individual amino acids from the ends of the protein chain.

Endopeptidases play a crucial role in various biological processes, such as digestion, blood coagulation, and programmed cell death (apoptosis). They are classified based on their catalytic mechanism and the structure of their active site. Some examples of endopeptidase families include serine proteases, cysteine proteases, aspartic proteases, and metalloproteases.

It is important to note that while endopeptidases are essential for normal physiological functions, they can also contribute to disease processes when their activity is unregulated or misdirected. For instance, excessive endopeptidase activity has been implicated in the pathogenesis of neurodegenerative disorders, cancer, and inflammatory conditions.

P-Chloromercuribenzoic acid (CMB) is not primarily considered a medical compound, but rather an organic chemical one. However, it has been used in some medical research and diagnostic procedures due to its ability to bind to proteins and enzymes. Here's the chemical definition:

P-Chloromercuribenzoic acid (CMB) is an organomercury compound with the formula C6H4ClHgO2. It is a white crystalline powder, soluble in water, and has a melting point of 208-210 °C. It is used as a reagent to study protein structure and function, as it can react with sulfhydryl groups (-SH) in proteins, forming a covalent bond and inhibiting their activity. This property has been exploited in various research and diagnostic applications. However, due to its toxicity and environmental concerns related to mercury, its use is now limited and regulated.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

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.

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.

Chymotrypsin is a proteolytic enzyme, specifically a serine protease, that is produced in the pancreas and secreted into the small intestine as an inactive precursor called chymotrypsinogen. Once activated, chymotrypsin helps to digest proteins in food by breaking down specific peptide bonds in protein molecules. Its activity is based on the recognition of large hydrophobic side chains in amino acids like phenylalanine, tryptophan, and tyrosine. Chymotrypsin plays a crucial role in maintaining normal digestion and absorption processes in the human body.

Tosyl compounds are organic compounds that contain the tosyl group (p-toluenesulfonyl, -SO2C6H4CH3) as a substituent. The tosyl group is a protecting group or a good leaving group in organic reactions. Tosyl compounds are often prepared by reacting alcohols or amines with p-toluenesulfonyl chloride (TsCl) in the presence of a base.

The general formula for a tosyl compound can be represented as R-OTs, where R represents an organic group such as an alkyl, aryl, or heteroaryl group. Tosyl compounds are widely used in organic synthesis due to their versatility and reactivity.

Trypsin inhibitors are substances that inhibit the activity of trypsin, an enzyme that helps digest proteins in the small intestine. Trypsin inhibitors can be found in various foods such as soybeans, corn, and raw egg whites. In the case of soybeans, trypsin inhibitors are denatured and inactivated during cooking and processing.

In a medical context, trypsin inhibitors may be used therapeutically to regulate excessive trypsin activity in certain conditions such as pancreatitis, where there is inflammation of the pancreas leading to the release of activated digestive enzymes, including trypsin, into the pancreas and surrounding tissues. By inhibiting trypsin activity, these inhibitors can help reduce tissue damage and inflammation.

Cysteine endopeptidases are a type of enzymes that cleave peptide bonds within proteins. They are also known as cysteine proteases or cysteine proteinases. These enzymes contain a catalytic triad consisting of three amino acids: cysteine, histidine, and aspartate. The thiol group (-SH) of the cysteine residue acts as a nucleophile and attacks the carbonyl carbon of the peptide bond, leading to its cleavage.

Cysteine endopeptidases play important roles in various biological processes, including protein degradation, cell signaling, and inflammation. They are involved in many physiological and pathological conditions, such as apoptosis, immune response, and cancer. Some examples of cysteine endopeptidases include cathepsins, caspases, and calpains.

It is important to note that these enzymes require a reducing environment to maintain the reduced state of their active site cysteine residue. Therefore, they are sensitive to oxidizing agents and inhibitors that target the thiol group. Understanding the structure and function of cysteine endopeptidases is crucial for developing therapeutic strategies that target these enzymes in various diseases.

Electrophoresis, polyacrylamide gel (EPG) is a laboratory technique used to separate and analyze complex mixtures of proteins or nucleic acids (DNA or RNA) based on their size and electrical charge. This technique utilizes a matrix made of cross-linked polyacrylamide, a type of gel, which provides a stable and uniform environment for the separation of molecules.

In this process:

1. The polyacrylamide gel is prepared by mixing acrylamide monomers with a cross-linking agent (bis-acrylamide) and a catalyst (ammonium persulfate) in the presence of a buffer solution.
2. The gel is then poured into a mold and allowed to polymerize, forming a solid matrix with uniform pore sizes that depend on the concentration of acrylamide used. Higher concentrations result in smaller pores, providing better resolution for separating smaller molecules.
3. Once the gel has set, it is placed in an electrophoresis apparatus containing a buffer solution. Samples containing the mixture of proteins or nucleic acids are loaded into wells on the top of the gel.
4. An electric field is applied across the gel, causing the negatively charged molecules to migrate towards the positive electrode (anode) while positively charged molecules move toward the negative electrode (cathode). The rate of migration depends on the size, charge, and shape of the molecules.
5. Smaller molecules move faster through the gel matrix and will migrate farther from the origin compared to larger molecules, resulting in separation based on size. Proteins and nucleic acids can be selectively stained after electrophoresis to visualize the separated bands.

EPG is widely used in various research fields, including molecular biology, genetics, proteomics, and forensic science, for applications such as protein characterization, DNA fragment analysis, cloning, mutation detection, and quality control of nucleic acid or protein samples.

Treponema is a genus of spiral-shaped bacteria, also known as spirochetes. These bacteria are gram-negative and have unique motility provided by endoflagella, which are located in the periplasmic space, running lengthwise between the cell's outer membrane and inner membrane.

Treponema species are responsible for several important diseases in humans, including syphilis (Treponema pallidum), yaws (Treponema pertenue), pinta (Treponema carateum), and endemic syphilis or bejel (Treponema pallidum subspecies endemicum). These diseases are collectively known as treponematoses.

It is important to note that while these bacteria share some common characteristics, they differ in their clinical manifestations and geographical distributions. Proper diagnosis and treatment of treponemal infections require medical expertise and laboratory confirmation.

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.

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.

An amino acid substitution is a type of mutation in which one amino acid in a protein is replaced by another. This occurs when there is a change in the DNA sequence that codes for a particular amino acid in a protein. The genetic code is redundant, meaning that most amino acids are encoded by more than one codon (a sequence of three nucleotides). As a result, a single base pair change in the DNA sequence may not necessarily lead to an amino acid substitution. However, if a change does occur, it can have a variety of effects on the protein's structure and function, depending on the nature of the substituted amino acids. Some substitutions may be harmless, while others may alter the protein's activity or stability, leading to disease.

Leupeptins are a type of protease inhibitors, which are substances that can inhibit the activity of enzymes called proteases. Proteases play a crucial role in breaking down proteins into smaller peptides or individual amino acids. Leupeptins are naturally occurring compounds found in some types of bacteria and are often used in laboratory research to study various cellular processes that involve protease activity.

Leupeptins can inhibit several different types of proteases, including serine proteases, cysteine proteases, and some metalloproteinases. They work by binding to the active site of these enzymes and preventing them from cleaving their protein substrates. Leupeptins have been used in various research applications, such as studying protein degradation, signal transduction pathways, and cell death mechanisms.

It is important to note that leupeptins are not typically used as therapeutic agents in clinical medicine due to their potential toxicity and lack of specificity for individual proteases. Instead, they are primarily used as research tools in basic science investigations.

Phenylmethylsulfonyl Fluoride (PMSF) is not a medication or a treatment, but it is a chemical compound with the formula C8H9FO3S. It is commonly used in biochemistry and molecular biology research as a serine protease inhibitor.

Proteases are enzymes that break down other proteins by cleaving specific peptide bonds. Serine proteases are a class of proteases that use a serine residue in their active site to carry out the hydrolysis reaction. PMSF works by irreversibly modifying this serine residue, inhibiting the enzyme's activity.

PMSF is used in laboratory settings to prevent protein degradation during experiments such as protein purification or Western blotting. It is important to note that PMSF is highly toxic and must be handled with care, using appropriate personal protective equipment (PPE) and safety measures.

Enzyme precursors are typically referred to as zymogens or proenzymes. These are inactive forms of enzymes that can be activated under specific conditions. When the need for the enzyme's function arises, the proenzyme is converted into its active form through a process called proteolysis, where it is cleaved by another enzyme. This mechanism helps control and regulate the activation of certain enzymes in the body, preventing unwanted or premature reactions. A well-known example of an enzyme precursor is trypsinogen, which is converted into its active form, trypsin, in the digestive system.

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.

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.

Thrombin is a serine protease enzyme that plays a crucial role in the coagulation cascade, which is a complex series of biochemical reactions that leads to the formation of a blood clot (thrombus) to prevent excessive bleeding during an injury. Thrombin is formed from its precursor protein, prothrombin, through a process called activation, which involves cleavage by another enzyme called factor Xa.

Once activated, thrombin converts fibrinogen, a soluble plasma protein, into fibrin, an insoluble protein that forms the structural framework of a blood clot. Thrombin also activates other components of the coagulation cascade, such as factor XIII, which crosslinks and stabilizes the fibrin network, and platelets, which contribute to the formation and growth of the clot.

Thrombin has several regulatory mechanisms that control its activity, including feedback inhibition by antithrombin III, a plasma protein that inactivates thrombin and other serine proteases, and tissue factor pathway inhibitor (TFPI), which inhibits the activation of factor Xa, thereby preventing further thrombin formation.

Overall, thrombin is an essential enzyme in hemostasis, the process that maintains the balance between bleeding and clotting in the body. However, excessive or uncontrolled thrombin activity can lead to pathological conditions such as thrombosis, atherosclerosis, and disseminated intravascular coagulation (DIC).

"Porphyromonas gingivalis" is a gram-negative, anaerobic, rod-shaped bacterium that is commonly found in the oral cavity and is associated with periodontal disease. It is a major pathogen in chronic periodontitis, which is a severe form of gum disease that can lead to destruction of the tissues supporting the teeth, including the gums, periodontal ligament, and alveolar bone.

The bacterium produces several virulence factors, such as proteases and endotoxins, which contribute to its pathogenicity. It has been shown to evade the host's immune response and cause tissue destruction through various mechanisms, including inducing the production of pro-inflammatory cytokines and matrix metalloproteinases.

P. gingivalis has also been linked to several systemic diseases, such as atherosclerosis, rheumatoid arthritis, and Alzheimer's disease, although the exact mechanisms of these associations are not fully understood. Effective oral hygiene practices, including regular brushing, flossing, and professional dental cleanings, can help prevent the overgrowth of P. gingivalis and reduce the risk of periodontal disease.

Hydrolysis is a chemical process, not a medical one. However, it is relevant to medicine and biology.

Hydrolysis is the breakdown of a chemical compound due to its reaction with water, often resulting in the formation of two or more simpler compounds. In the context of physiology and medicine, hydrolysis is a crucial process in various biological reactions, such as the digestion of food molecules like proteins, carbohydrates, and fats. Enzymes called hydrolases catalyze these hydrolysis reactions to speed up the breakdown process in the body.

Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:

1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.

Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.

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.

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.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Cysteine proteinase inhibitors are a type of molecule that bind to and inhibit the activity of cysteine proteases, which are enzymes that cleave proteins at specific sites containing the amino acid cysteine. These inhibitors play important roles in regulating various biological processes, including inflammation, immune response, and programmed cell death (apoptosis). They can also have potential therapeutic applications in diseases where excessive protease activity contributes to pathology, such as cancer, arthritis, and neurodegenerative disorders. Examples of cysteine proteinase inhibitors include cystatins, kininogens, and serpins.

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.

Oligopeptides are defined in medicine and biochemistry as short chains of amino acids, typically containing fewer than 20 amino acid residues. These small peptides are important components in various biological processes, such as serving as signaling molecules, enzyme inhibitors, or structural elements in some proteins. They can be found naturally in foods and may also be synthesized for use in medical research and therapeutic applications.

Cycloheximide is an antibiotic that is primarily used in laboratory settings to inhibit protein synthesis in eukaryotic cells. It is derived from the actinobacteria species Streptomyces griseus. In medical terms, it is not used as a therapeutic drug in humans due to its significant side effects, including liver toxicity and potential neurotoxicity. However, it remains a valuable tool in research for studying protein function and cellular processes.

The antibiotic works by binding to the 60S subunit of the ribosome, thereby preventing the transfer RNA (tRNA) from delivering amino acids to the growing polypeptide chain during translation. This inhibition of protein synthesis can be lethal to cells, making cycloheximide a useful tool in studying cellular responses to protein depletion or misregulation.

In summary, while cycloheximide has significant research applications due to its ability to inhibit protein synthesis in eukaryotic cells, it is not used as a therapeutic drug in humans because of its toxic side effects.

Bacteroides are a genus of gram-negative, anaerobic, rod-shaped bacteria that are normally present in the human gastrointestinal tract. They are part of the normal gut microbiota and play an important role in breaking down complex carbohydrates and other substances in the gut. However, some species of Bacteroides can cause opportunistic infections, particularly in individuals with weakened immune systems or when they spread to other parts of the body. They are resistant to many commonly used antibiotics, making infections caused by these bacteria difficult to treat.

NF-κB (Nuclear Factor kappa-light-chain-enhancer of activated B cells) is a protein complex that plays a crucial role in regulating the immune response to infection and inflammation, as well as in cell survival, differentiation, and proliferation. It is composed of several subunits, including p50, p52, p65 (RelA), c-Rel, and RelB, which can form homodimers or heterodimers that bind to specific DNA sequences called κB sites in the promoter regions of target genes.

Under normal conditions, NF-κB is sequestered in the cytoplasm by inhibitory proteins known as IκBs (inhibitors of κB). However, upon stimulation by various signals such as cytokines, bacterial or viral products, and stress, IκBs are phosphorylated, ubiquitinated, and degraded, leading to the release and activation of NF-κB. Activated NF-κB then translocates to the nucleus, where it binds to κB sites and regulates the expression of target genes involved in inflammation, immunity, cell survival, and proliferation.

Dysregulation of NF-κB signaling has been implicated in various pathological conditions such as cancer, chronic inflammation, autoimmune diseases, and neurodegenerative disorders. Therefore, targeting NF-κB signaling has emerged as a potential therapeutic strategy for the treatment of these diseases.

Protein precursors, also known as proproteins or prohormones, are inactive forms of proteins that undergo post-translational modification to become active. These modifications typically include cleavage of the precursor protein by specific enzymes, resulting in the release of the active protein. This process allows for the regulation and control of protein activity within the body. Protein precursors can be found in various biological processes, including the endocrine system where they serve as inactive hormones that can be converted into their active forms when needed.

Essential amino acids are a group of 9 out of the 20 standard amino acids that cannot be synthesized by the human body and must be obtained through diet. They include: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. These amino acids are essential for various biological processes such as protein synthesis, growth, and repair of body tissues. A deficiency in any of these essential amino acids can lead to impaired physical development and compromised immune function. Foods that provide all nine essential amino acids are considered complete proteins and include animal-derived products like meat, poultry, fish, eggs, and dairy, as well as soy and quinoa.

"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.

Methyl n-Butyl Ketone, also known as Methyl Amyl Ketone or 2-Hexanone, is an organic compound with the molecular formula C6H12O. It is a colorless liquid with a pungent, fruity odor. It is used as a solvent in various industrial applications, including coatings, cleaning agents, and adhesives.

In a medical context, Methyl n-Butyl Ketone is primarily relevant as a potential occupational hazard. Exposure to this chemical can occur through inhalation, skin contact, or accidental ingestion during its use in industrial settings. Acute exposure to high levels of Methyl n-Butyl Ketone can lead to symptoms such as headache, dizziness, nausea, and respiratory irritation. Chronic exposure has been associated with neurological issues, including memory loss, confusion, and peripheral neuropathy.

It is essential for medical professionals to be aware of the potential health effects of Methyl n-Butyl Ketone, particularly in occupational settings, to ensure appropriate prevention measures are in place and to diagnose and manage potential exposures effectively.

Amino acid transport systems refer to the various membrane transport proteins that are responsible for the active or passive translocation of amino acids across cell membranes in the body. These transport systems play a crucial role in maintaining amino acid homeostasis within cells and regulating their availability for protein synthesis, neurotransmission, and other physiological processes.

There are several distinct amino acid transport systems, each with its own specificity for particular types of amino acids or related molecules. These systems can be classified based on their energy requirements, substrate specificity, and membrane localization. Some of the major amino acid transport systems include:

1. System A - This is a sodium-dependent transport system that primarily transports small, neutral amino acids such as alanine, serine, and proline. It has several subtypes (ASC, A, and AN) with different substrate affinities and kinetic properties.
2. System L - This is a sodium-independent transport system that transports large, neutral amino acids such as leucine, isoleucine, valine, phenylalanine, and tryptophan. It has several subtypes (L1, L2, and y+L) with different substrate specificities and transport mechanisms.
3. System B0 - This is a sodium-dependent transport system that transports both neutral and basic amino acids such as arginine, lysine, and ornithine. It has several subtypes (B0,+, B0-, and b0,+) with different substrate affinities and kinetic properties.
4. System y+ - This is a sodium-independent transport system that transports primarily basic amino acids such as arginine, lysine, and ornithine. It has several subtypes (y+L, y+, b0,+) with different substrate specificities and transport mechanisms.
5. System X-AG - This is a sodium-independent antiporter system that exchanges glutamate and aspartate for neutral amino acids such as cystine, serine, and threonine. It plays an essential role in maintaining redox homeostasis by regulating the intracellular levels of cysteine, a precursor of glutathione.

These transport systems are critical for maintaining cellular homeostasis and regulating various physiological processes such as protein synthesis, neurotransmission, and immune function. Dysregulation of these transport systems has been implicated in several diseases, including cancer, neurological disorders, and cardiovascular disease. Therefore, understanding the molecular mechanisms underlying these transport systems is essential for developing novel therapeutic strategies to treat these conditions.

Acetoacetates are compounds that are produced in the liver as a part of fatty acid metabolism, specifically during the breakdown of fatty acids for energy. Acetoacetates are formed from the condensation of two acetyl-CoA molecules and are intermediate products in the synthesis of ketone bodies, which can be used as an alternative energy source by tissues such as the brain during periods of low carbohydrate availability or intense exercise.

In clinical settings, high levels of acetoacetates in the blood may indicate a condition called diabetic ketoacidosis (DKA), which is a complication of diabetes mellitus characterized by high levels of ketone bodies in the blood due to insulin deficiency or resistance. DKA can lead to serious complications such as cerebral edema, cardiac arrhythmias, and even death if left untreated.

In genetics, sequence alignment is the process of arranging two or more DNA, RNA, or protein sequences to identify regions of similarity or homology between them. This is often done using computational methods to compare the nucleotide or amino acid sequences and identify matching patterns, which can provide insight into evolutionary relationships, functional domains, or potential genetic disorders. The alignment process typically involves adjusting gaps and mismatches in the sequences to maximize the similarity between them, resulting in an aligned sequence that can be visually represented and analyzed.

3-Hydroxybutyric acid, also known as β-hydroxybutyric acid, is a type of ketone body that is produced in the liver during the metabolism of fatty acids. It is a colorless, slightly water-soluble compound with a bitter taste and an unpleasant odor.

In the body, 3-hydroxybutyric acid is produced when there is not enough glucose available to meet the body's energy needs, such as during fasting, starvation, or prolonged intense exercise. It can also be produced in large amounts in people with uncontrolled diabetes, particularly during a condition called diabetic ketoacidosis.

3-Hydroxybutyric acid is an important source of energy for the brain and other organs during periods of low glucose availability. However, high levels of 3-hydroxybutyric acid in the blood can lead to a condition called ketosis, which can cause symptoms such as nausea, vomiting, abdominal pain, and confusion. If left untreated, ketosis can progress to diabetic ketoacidosis, a potentially life-threatening complication of diabetes.

Enzyme activation refers to the process by which an enzyme becomes biologically active and capable of carrying out its specific chemical or biological reaction. This is often achieved through various post-translational modifications, such as proteolytic cleavage, phosphorylation, or addition of cofactors or prosthetic groups to the enzyme molecule. These modifications can change the conformation or structure of the enzyme, exposing or creating a binding site for the substrate and allowing the enzymatic reaction to occur.

For example, in the case of proteolytic cleavage, an inactive precursor enzyme, known as a zymogen, is cleaved into its active form by a specific protease. This is seen in enzymes such as trypsin and chymotrypsin, which are initially produced in the pancreas as inactive precursors called trypsinogen and chymotrypsinogen, respectively. Once they reach the small intestine, they are activated by enteropeptidase, a protease that cleaves a specific peptide bond, releasing the active enzyme.

Phosphorylation is another common mechanism of enzyme activation, where a phosphate group is added to a specific serine, threonine, or tyrosine residue on the enzyme by a protein kinase. This modification can alter the conformation of the enzyme and create a binding site for the substrate, allowing the enzymatic reaction to occur.

Enzyme activation is a crucial process in many biological pathways, as it allows for precise control over when and where specific reactions take place. It also provides a mechanism for regulating enzyme activity in response to various signals and stimuli, such as hormones, neurotransmitters, or changes in the intracellular environment.

Fluorescent dyes are substances that emit light upon excitation by absorbing light of a shorter wavelength. In a medical context, these dyes are often used in various diagnostic tests and procedures to highlight or mark certain structures or substances within the body. For example, fluorescent dyes may be used in imaging techniques such as fluorescence microscopy or fluorescence angiography to help visualize cells, tissues, or blood vessels. These dyes can also be used in flow cytometry to identify and sort specific types of cells. The choice of fluorescent dye depends on the specific application and the desired properties, such as excitation and emission spectra, quantum yield, and photostability.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Amino acid motifs are recurring patterns or sequences of amino acids in a protein molecule. These motifs can be identified through various sequence analysis techniques and often have functional or structural significance. They can be as short as two amino acids in length, but typically contain at least three to five residues.

Some common examples of amino acid motifs include:

1. Active site motifs: These are specific sequences of amino acids that form the active site of an enzyme and participate in catalyzing chemical reactions. For example, the catalytic triad in serine proteases consists of three residues (serine, histidine, and aspartate) that work together to hydrolyze peptide bonds.
2. Signal peptide motifs: These are sequences of amino acids that target proteins for secretion or localization to specific organelles within the cell. For example, a typical signal peptide consists of a positively charged n-region, a hydrophobic h-region, and a polar c-region that directs the protein to the endoplasmic reticulum membrane for translocation.
3. Zinc finger motifs: These are structural domains that contain conserved sequences of amino acids that bind zinc ions and play important roles in DNA recognition and regulation of gene expression.
4. Transmembrane motifs: These are sequences of hydrophobic amino acids that span the lipid bilayer of cell membranes and anchor transmembrane proteins in place.
5. Phosphorylation sites: These are specific serine, threonine, or tyrosine residues that can be phosphorylated by protein kinases to regulate protein function.

Understanding amino acid motifs is important for predicting protein structure and function, as well as for identifying potential drug targets in disease-associated proteins.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.

Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.

Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.

'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.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

The phenylalanine moiety is bound to the enzyme because of specificity for aromatic amino acid residues at the active site (as ... Tosyl phenylalanyl chloromethyl ketone (TPCK) is a protease inhibitor. Its structural formula is 1-chloro-3-tosylamido-4-phenyl ... The chloromethyl group reacts with the active site cysteine to form a covalent bond with the loss of the chlorine. TPCK is ...
It is a popular method of producing β-amino acids from α-amino acids. Aside from the acid chloride substrate, three reagents ... Not taking diazomethane in excess results in HCl reacting with the diazoketone to form chloromethyl ketone and N2. Mild ... Acid anhydrides can be used in place of acid chloride. The reaction yields a 1:1 mixture of the homologated acid and the ... The preparation of the beta-amino acid from phenylalanine illustrates the Arndt-Eistert synthesis carried out with the Newman- ...
TAILS is also compatible with Stable isotope labeling by amino acids in cell culture (SILAC). COFRADIC was the earliest ... Zymogen/enzyme discrimination using peptide chloromethyl ketones J. Biol. Chem., 264 (13) 7536-7545 (1989). Kidd D., Liu Y., ... Standard peptides synthesized from amino acids labeled with stable isotope atoms serve as internal standards for serial ... enzymatic activity profiling in complex proteomes Amino Acids, 30 (4) 333-350 (2006). Greenbaum D.C., Baruch A., Grainger M., ...
... ester Phosphonothioic acid, methyl-, S-(2-(bis(1-methylethyl)amino)ethyl) O-ethyl ester Phosphonothioic acid, methyl-, O-(4- ... chloromethyl) ketone Bitoscanate Boron trichloride Boron trifluoride Boron trifluoride compound with dimethyl ether (1:1) ... Chlormequat chloride Chloroacetic acid 2-chloroethanol Chloroethyl chloroformate Chloroform Chloromethyl ether Chloromethyl ... 4-amino- Pyridine, 4-nitro-, 1-oxide Pyriminil Ricin Salcomine Sarin Selenious acid Semicarbazide hydrochloride Silane, (4- ...
... cuts peptide chains mainly at the carboxyl side of the amino acids lysine or arginine. It is used for numerous ... The activity of trypsin is not affected by the enzyme inhibitor tosyl phenylalanyl chloromethyl ketone, TPCK, which deactivates ... This means that trypsin predominantly cleaves proteins at the carboxyl side (or "C-terminal side") of the amino acids lysine ... The peptide products are then further hydrolyzed into amino acids via other proteases, rendering them available for absorption ...
... chloromethyl ketone formation (4) with hydrochloric acid, organic reduction of chlorine to methylketone (5), ketone ... Has been used to convert β-amino esters from α-amino esters through an ynolate intermediate. Seyferth-Gilbert homologation in ... pyruvic acid is removed from a linear aliphatic carboxylic acid yielding a new acid with 2 carbon atoms less. The original ... Arndt-Eistert reaction is a series of chemical reactions designed to convert a carboxylic acid to a higher carboxylic acid ...
The heavy chain originates from the amino-terminal end of the zymogen and contains 4 tandem repeats of 90 or 91 amino acids. ... "Synthesis of tripeptide chloromethyl ketones and examination of their inhibitory effects on plasmin and plasma kallikrein". ... Fujikawa K, Chung DW, Hendrickson LE, Davie EW (1986). "Amino acid sequence of human factor XI, a blood coagulation factor with ... and trypsin with amino acid and peptide thioesters: development of new sensitive substrates". Biochemistry. 20 (25): 7196-206. ...
... iodoacetic acid, EDTA or by other serine protease inhibitors like Nα-Tosyl-Lys Chloromethyl Ketone (TLCK) and Nα-Tosyl-Phe ... the enzyme digests proteins preferentially after hydrophobic amino acids (aliphatic, aromatic and other hydrophobic amino acids ... N-alpha-tosyl-L-lysyl-chloromethyl-ketone (TLCK), or N-alpha-Tosyl-l-phenylalanine Chloromethyl Ketone (TPCK), although ... Jany KD, Lederer G, Mayer B (1986). "Amino acid sequence of proteinase K from the mold Tritirachium album Limber". FEBS Lett. ...
The 5-methyl group can be variously oxidized to chloromethyl, aldehyde, or carboxylic acid functionality by the use of ... The method involves the reaction of an α-amino-ketone (1) and a compound containing an electron-withdrawing group (e.g. an ... and tertiary-butyl groups can be removed by treatment with trifluoroacetic acid, or boiling aqueous acetic acid. R1 and R3 (as ... The mechanism of the Knorr pyrrole synthesis begins with condensation of the amine and ketone to give an imine. The imine then ...
... tosylphenylalanyl chloromethyl ketone MeSH D12.125.067.500 - aspartic acid MeSH D12.125.067.500.150 - d-aspartic acid MeSH ... 2-amino-5-phosphonovalerate MeSH D12.125.072.050 - amino acids, aromatic MeSH D12.125.072.050.342 - dextrothyroxine MeSH ... 2-aminoadipic acid MeSH D12.125.119.170 - aspartic acid MeSH D12.125.119.170.150 - d-aspartic acid MeSH D12.125.119.170.275 - ... aspartic acid MeSH D12.125.427.300 - glutamic acid MeSH D12.125.481.100 - allylglycine MeSH D12.125.481.700 - n-substituted ...
The amino acid serine is a source of natural formaldehyde according to this reaction, which produces glycine: HOCH2CH(NH2)CO2H ... Transition metal complexes of aldehydes and ketones includes several complexes of formaldehyde. 1,3-Dioxetane DMDM hydantoin ... the product is the chloromethyl compound, as described in the Blanc chloromethylation. If the arene is electron-rich, as in ... Formaldehyde, formed in the metabolism of the amino acids serine and threonine, is found in the bloodstream of humans and other ...
In the next step the vinyl silane 11 reacts with peracetic acid in acetic acid in a radical substitution to the dilactone 12 ... The newly formed ketone group then forms another C-C bond by photochemical Norrish reaction to 19 whose alcohol group is ... Amino-dodecahedranes comparable to amantadine have been prepared, but were more toxic and with weaker antiviral effects. ... with the immediate reaction product trapped with chloromethyl phenyl ether, the other chlorine atom in 17 is simply reduced. ...
The same year they also described a «polysilicic acid ether» in the preparation of ethyl- and methyl-o-silicic acid. Extensive ... He also had coined the term "silicone" (resembling ketones, this is errorneous though): 286 in relation to these materials in ... More specialized derivatives that find commercial applications include dichloromethylphenylsilane, trichloro(chloromethyl) ... "Synthesis and Structure of a Base-Stabilized C-Phosphino-Si-Amino Silyne". Angewandte Chemie International Edition. 49 (37): ...
... tosyllysine chloromethyl ketone MeSH D02.455.426.559.389.832.710 - tosylphenylalanyl chloromethyl ketone MeSH D02.455.426.559. ... trinitrobenzenesulfonic acid MeSH D02.640.600.200 - 5-amino-3-((5-nitro-2-furyl)vinyl)-1,2,4-oxadiazole MeSH D02.640.600.290 - ... tosyllysine chloromethyl ketone MeSH D02.886.590.887.660 - tosylphenylalanyl chloromethyl ketone MeSH D02.886.640.150 - ... quinic acid MeSH D02.241.511.852 - shikimic acid MeSH D02.241.511.902 - sugar acids MeSH D02.241.511.902.107 - ascorbic acid ...
The phenylalanine moiety is bound to the enzyme because of specificity for aromatic amino acid residues at the active site (as ... Tosyl phenylalanyl chloromethyl ketone (TPCK) is a protease inhibitor. Its structural formula is 1-chloro-3-tosylamido-4-phenyl ... The chloromethyl group reacts with the active site cysteine to form a covalent bond with the loss of the chlorine. TPCK is ...
Amino Acid Chloromethyl Ketones (MeSH) * Amino Acid Sequence (MeSH) * Antithrombin III (MeSH) ...
The synthesis of the chloromethyl ketone group generally involves the reaction of a blocked amino acid with a chloroformate to ... The n termini of amino acid monomers is protected by either of these two groups and added onto a deprotected amino acid chain. ... If peptide fluoromethyl ketones are to become as readily available as the chloromethyl ketones, then new methods must be found ... Ketone enolates can be acylated with nonenolisable esters i. Chloromethylketones chloromethylketones inhibitors. The ...
The deduced amino-acid sequence shows extensive similarity to cysteine proteases of other parasitic protozoa, as well as papain ... Both peptidyl chloromethyl ketones and peptidyl phosphonate diphenyl esters inhibited trypsin-like peptidases of the parasites ... Instead, it had activity toward substrates of trypsin-like enzymes, particularly those that have basic amino acids in both P(1 ... The enzyme has trypsin-like specificity since it cleaved fluorogenic peptides that have basic amino acid residues (Arg or Lys) ...
a: aromatic amino acid. C: cysteine, involved in disulphide bond. x: any amino acid.. ... Crystal Structure of Glu-Gly-Arg-Chloromethyl Ketone-Factor VIIa/Soluble Tissue Factor Complex. ... A sequence of about forty amino-acid residues found in epidermal growth factor (EGF) has been shown [ (PUBMED:2288911) (PUBMED: ... 2017) Nucleic Acids Res doi: 10.1093/nar/gkx922. Letunic et al. (2020) Nucleic Acids Res doi: 10.1093/nar/gkaa937 ...
Amino Acid Chloromethyl Ketones. *Amino Acids, Acidic. *Amino Acids, Basic. *Amino Acids, Branched-Chain ... A non-essential amino acid that occurs in high levels in its free state in plasma. It is produced from pyruvate by ... Alanine Scanning of the Unstructured Region of Ara h 2 and of a Related Mimotope Reveals Critical Amino Acids for IgE Binding. ... It is involved in sugar and acid metabolism, increases IMMUNITY, and provides energy for muscle tissue, BRAIN, and the CENTRAL ...
Ketones, Monoterpene use Monoterpene Aldehydes and Ketones Ketones, Peptide Chloromethyl use Amino Acid Chloromethyl Ketones ... Ketone, Tosyllysine Chloromethyl use Tosyllysine Chloromethyl Ketone Ketone, Tosylphenylalanyl Chloromethyl use ... Ketol-Acid Reductoisomerase Ketol-Isomerase, 2-Amino-2-Deoxy-D-Glucose-6-Phosphate use Glutamine-Fructose-6-Phosphate ... Ketone, Methyl n-Butyl use Methyl n-Butyl Ketone ... Kainic Acid Receptor use Receptors, Kainic Acid Kainic Acid ...
Ketones, Methyl Propyl use Pentanones Ketones, Peptide Chloromethyl use Amino Acid Chloromethyl Ketones ... Ketone, Tosyllysine Chloromethyl use Tosyllysine Chloromethyl Ketone Ketone, Tosylphenylalanyl Chloromethyl use ... Ketol-Acid Reductoisomerase Ketol-Isomerase, 2-Amino-2-Deoxy-D-Glucose-6-Phosphate use Glutamine-Fructose-6-Phosphate ... Ketone, Methyl n-Butyl use Methyl n-Butyl Ketone ... Kainic Acid Receptor use Receptors, Kainic Acid Kainic Acid ...
LC-MS/MS detection method can provide high sensitivity for identification of specific proteins based on their amino acid ... L-1-tosylamido-2-phenylethyl chloromethyl ketone) treated trypsin was from AB SCIEX (Foster City, CA). Strong cation exchange ( ... Table 1 presents the precursor ions from SKBR3 lysate matching a number of peptides based on MMP1 amino acid sequences (MMP1_ ... The eluted fractions were dried again and reconstituted in 0.5 ml of 0.1% trifluoroacetic acid (TFA) in water before applying ...
Sirtuin 3Voltage-Dependent Anion Channel 2Enzyme InhibitorsIsocitratesTrityl CompoundsAmino Acid Chloromethyl Ketones ... Amino acid residues 1-28 of Bcl-xL fused to EGFP are sufficient to target mitochondria. Although positive charges and helical ... Plant cells can form all the amino acids. Many vacuoles occur, which are smaller in size. (d) the chloroplasts are generally ... The function of fatty acid biosynthesis in mitochondria has remained an enigma. In eukaryotic plants, synthesis of fatty acids ...
However, variations in the gene and amino acid sequences in different influenza virus subtypes due to rapid mutations of the ... cells with tosyl sulfonyl phenylalanyl chloromethyl ketone- (TPCK-) treated trypsin (2 µg/ml) (Sigma, St. Louis, MO) as ... Nucleic acid was recovered in 110 µl elution buffer. By using a parallel specimen (300 µl), nucleic acid extraction, PCR, and ... Nucleic Acid Extraction. Nucleic acid was detected using easyMAG extraction platform (bioMérieux, Marcy lÉtoile, France) and ...
Residue substitution R374I (B numbering) is only 3 amino acids long and does have a proven effect on NAI susceptibility. To ... 2 mL/well minimal essential medium supplemented with 2 mg/mL tosyl phenylalanyl chloromethyl ketone trypsin was added. Cells ... B/Morocco/CP10/2015 harboured amino acid substitution K371N (B numbering) located among the highly conserved catalytic NA ... and are associated with amino acid substitutions at the conserved NA residues or in surrounding locations (8). ...
... that a p15 BID polypeptide can comprise a modified amino acid or unusual amino acid at one or more positions in its amino acid ... p-tosyl-L-lysine chloromethyl ketone (TLCK). To remove the GST protein and incompletely cleaved fusion proteins, the ... For example, one grouping of amino acids includes those amino acids that have neutral and hydrophobic side chains (A, V, L, I, ... Preferably, amino acid positions which are not identical differ by conservative amino acid substitutions. ...
... most amino acid substitutions were nonpermissive for the in vivo biogenesis of CFTR (Du et al., 2005; Thibodeau et al., 2005 ... N-Tosyl-l-phenylalanine chloromethyl ketone-treated trypsin was purchased from Worthington Biochemicals (Freehold, NJ), and ... Depending on the amino acid packing density and hydrophobicity at the interface, this mechanism itself or in combination with ... Amino acid substitutions at the 508 position were permissive for the NBD1 folding, whereas deletion of F508 decreased the ...
First-order nociceptive synapses in rat dorsal horn are blocked by an amino acid antagonist. Schouenborg, J. & Sjölund, B. H., ... Tosyllysine Chloromethyl Ketone 100% * Axonal Transport 70% * Peptide Hydrolases 47% * Anura 17% ...
"1-Amino-2,4-dibromoanthraquinone" DTXSID4039235 NC1=C2C(=O)C3=C(C=CC=C3)C(=O)C2=C(Br)C=C1Br ZINRVIQBCHAZMM-UHFFFAOYSA-N NC1=C2C ... RAHC ROC Edition 14 90-94-8 Michlers ketone DTXSID2020894 CN(C)C1=CC=C(C=C1)C(=O)C1=CC=C(C=C1)N(C)C VVBLNCFGVYUYGU-UHFFFAOYSA- ... CCCO1 RAHC ROC Edition 14 115-28-6 Chlorendic acid DTXSID2020268 OC(=O)C1C(C(O)=O)C2(Cl)C(Cl)=C(Cl)C1(Cl)C2(Cl)Cl ... Chloromethyl) ether DTXSID8020173 ClCOCCl HRQGCQVOJVTVLU-UHFFFAOYSA-N ClCOCCl Known ROC Edition 14 54749-90-5 Chlorozotocin ...
Chen Y. Selective inhibition of Ras-transformed cell growth by a novel fatty acid-based chloromethyl ketone designed to target ... amino acids and then a widely variable amino acid. Nascent Ras proteins that display a CAAX sequence after release from ... These proteins terminate in a CAAX sequence where cysteine is the fourth to last amino acid and is followed by two, usually ... Next the AAX amino acids are removed by a farnesylcysteine-directed endoprotease known as Ras converting enzyme 1 (Rce1). ...
Methyl isobutyl ketone,Methyl isobutyl ketone (MIBK),Methyl isocyanate (MIC),Methyl isopropyl ketone Delisted April 4, 2014 [ ... 1-Amino-2-methylanthraquinone, 2-Amino-5-(5-nitro-2-furyl)-1,3,4-thiadiazole,4-Amino-2-nitrophenol,Aminopterin,Amiodarone ... 2-Chloropropionic acid,Chlorothalonil,p-Chloro-o-toluidine,p-Chloro-o-toluidine, strong acid salts of, p-Chloro-o-toluidine, ... chloromethyl)ether,Bis(2-chloro-1-methylethyl)ether, technical grade,Bisphenol A (BPA),Bitumens, extracts of steam-refined and ...
Methyl isobutyl ketone,Methyl isobutyl ketone (MIBK),Methyl isocyanate (MIC),Methyl isopropyl ketone Delisted April 4, 2014 [ ... 1-Amino-2-methylanthraquinone, 2-Amino-5-(5-nitro-2-furyl)-1,3,4-thiadiazole,4-Amino-2-nitrophenol,Aminopterin,Amiodarone ... 2-Chloropropionic acid,Chlorothalonil,p-Chloro-o-toluidine,p-Chloro-o-toluidine, strong acid salts of, p-Chloro-o-toluidine, ... chloromethyl)ether,Bis(2-chloro-1-methylethyl)ether, technical grade,Bisphenol A (BPA),Bitumens, extracts of steam-refined and ...
Chromic Acid on Anion Exchange Resin. Synthesis of Aldehydes and Ketones from Allylic and Benzylic Halides. Tetrahedron Lett. ... The nitrogen atom forms a secondary amino group, while the iminodiacetic acid anion may function as a tridentate ligand to form ... reaction of ethylenediamine with chloromethyl polystyrene polymer, and bonding of imine acetate group to the surface of ... The chemical formula of iminodiacetic acid (a dicarboxylic acid amine) is HN (CH2COOH)2, and is generally abbreviated as IDA. ...
Chloromethyl phenyl ketone. Ethanone, 2-chloro-1-phenyl. Phenyl chloromethyl ketone. Phenyl chloromethylketone. Tear gas. 2810 ... Phosphonothioic acid, methyl-, S-(2-(bis(1-methylethyl)amino)ethyl) O-ethyl ester. Phosphonothioic acid, methyl-, S-(2-( ... Anhydrous hydrofluoric acid. Antisal 2b. Deuteriumfluoride. Etching acid. Fluohydric acid. Fluorhydric acid. Fluoric acid. ... Methylphosphonothioic acid S- (2-(bis(1-methylethyl)amino)ethyl) O-ethyl ester. Methylphosphonothioic acid S- (2-(bis( ...
S)-2-Amino-5-guanidinopentanoic acid *cis-Butenedioic acid, Toxilic acid *1,2-Epoxypropane ... Chloromethyl)benzene , ?-Chlorotoluene *2,3,4,6,7,8,9,10-Octahydropyrimidol[1,2-a]azepine, DBU ... Isobutyl methyl ketone; Isopropylacetone; MIBK; Methyl isobutyl ketone *n-Heptane, Heptanes *Pentane ...
To a solution of ,strong,[150812-32-1]2-amino-4-bromo-5-chlorobenzoic acid,/strong, (500 mg,2mmol) in EtOH (20 mL) at RT, ... benzyl 2-(2-chloromethyl)allyl-3-hydroxypiperidine-1-carboxylate [ No CAS ]. *. * [ 17518-98-8 ] ... 7-Bromo-6-chloroquinazolin-4-ol To a solution of ,strong,[150812-32-1]2-amino-4-bromo-5-chlorobenzoic acid,/strong, (500 mg, ... 2S,3R)-2-amino-N-((E)-4-(7-bromo-6-chloro-4-oxoquinazolin-3(4H)-yl)but-2-en-1-yl)-3-hydroxybutanamide [ No CAS ] ...
2-AMINO-2-PHENYL BUTYRIC ACID CAS NO 5438-07-3. *BENZOPHENONE HYDRAZONE cas 5350-57-2 ... 1 Chloromethyl Naphthalene. *Glycerol Mono Oleate. *META CHLORO BENZO NITRILE CAS No: 766-84-7 ... 5-CHLORO SALICYLIC ACID. Price : 5 USD ($)/Kilograms. Minimum Order Quantity : 100. Send Inquiry ... 4 HYDROXY 2 METHYL 2H 12 BENZOTHIAZINE CARBOXYLIC ACID METHYL ESTER 1 1 DIOXIDE CAS No. : 35511-15-0 ...
1-AMINO-2-NAPHTHOL-4-SULPHONIC ACID. *1-AMINO-2-NAPHTHOL-4-SULPHONIC ACID AR ... 1-Decane Sulfonic Acid Sodium Salt Monohydrate (For HPLC). *Propane Sulfonic. * Ketones *Acetyl Acetone ... Chloromethyl thiocyanate. *Guanidinium thiocyanate. *Ethyl Thiocyanate. *4-fluorophenyl Isothiocyanate. *1-Ethyl-3- ...
6-Amino-m-toluic acid (COOH=1);6-AMINO-M-TOLUIC ACID 97+%;5-Methylanthranilic acid, 2-Carboxy-4-methylaniline, 6-Amino-m-toluic ... Chloromethyl)benzoic acid 1642-81-5 , CAS 1642-81-5 , Methyl 4-(chloromethyl)benzoate CAS 34040-64-7 , 1-ISOPROPENYL-2- ... 2-AMINO-5-NITROBENZONITRILE , ETHYL-P-TOLYLKETON;LABOTEST-BB LT00053050;P-TOLYL ETHYL KETONE;P-METHYLPROPIOPHENONE;4- ... 4-Amino-3-nitrobenzoic acid CAS 1588-83-6 , 2-Chloro-4-nitrobenzoic acid CAS 99-60-5 , 2-Amino-5-fluorobenzoic acid CAS 446-08- ...
  • The phenylalanine moiety is bound to the enzyme because of specificity for aromatic amino acid residues at the active site (as in chymotrypsin, in which it binds to the Histidine-57 residue in the active site). (wikipedia.org)
  • We present here a new, general, solid phase strategy for the synthesis of sequence independent peptidylfluoromethyl ketones using standard fmoc peptide. (web.app)
  • A sequence of about forty amino-acid residues found in epidermal growth factor (EGF) has been shown [ ( PUBMED:2288911 ) ( PUBMED:6334307 ) ( PUBMED:3534958 ) ( PUBMED:6607417 ) ( PUBMED:3282918 ) ] to be present in a large number of membrane-bound and extracellular, mostly animal, proteins. (embl.de)
  • These proteins terminate in a CAAX sequence where cysteine is the fourth to last amino acid and is followed by two, usually aliphatic, amino acids and then a widely variable amino acid. (cancer.gov)
  • Synthesis of peptides of arginine chloromethyl ketone. (web.app)
  • The chloromethyl group reacts with the active site cysteine to form a covalent bond with the loss of the chlorine. (wikipedia.org)
  • C': cysteine, involved in disulphide bond 'x': any amino acid. (embl.de)
  • Synthesis and properties of novel polyaryl ether ketones. (web.app)
  • For metabolized to reactive electro- icity in humans, but the classification bis(chloromethyl)ether (BCME), the philes. (who.int)
  • A metalfree oxidative coupling of methyl ketones and primary or secondary amines to. (web.app)
  • LC-MS/MS detection method can provide high sensitivity for identification of specific proteins based on their amino acid sequences and SRM-MS can provide absolute quantitation through a purified protein standard. (scirp.org)
  • However, variations in the gene and amino acid sequences in different influenza virus subtypes due to rapid mutations of the viral RNA polymerase may affect the results of these tests. (hindawi.com)
  • We are pursuing other carboncarbon bondforming reactions with the aim of developing a general method for the synthesis of optically active peptide fluoromethyl ketone derivatives. (web.app)
  • The synthesis of the chloromethyl ketone group generally involves the reaction of a blocked amino acid with a chloroformate to produce a mixed anhydride. (web.app)
  • If peptide fluoromethyl ketones are to become as readily available as the chloromethyl ketones, then new methods must be found for their synthesis. (web.app)
  • A non-essential amino acid that occurs in high levels in its free state in plasma. (ucdenver.edu)
  • The type of death was apoptotic by several criteria, including induction by Fas, inhibition by the caspase inhibitor zVAD-fmk (zVal-Ala-Asp-fluoro-methyl ketone), activation of DEVDase activity (Asp-Glu-Val-Asp protease), specific cleavage of caspase-3, DNA fragmentation, and increased Annexin-V labeling. (nih.gov)
  • Specific amino acids that have been subjected to mutational analysis are indicated by the single letter code corresponding to the residue present in the wild-type HPV-16 E7. (nih.gov)

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