Therapeutic Enzymes
... to immune reactions. Finally large quantities of DNA are released from damaged microbes and neutrophils at the site of infection. High molecular mass DNA is itself extremely viscous and increases substantially the viscosity of the respiratory mucus ...
... to immune reactions. Finally large quantities of DNA are released from damaged microbes and neutrophils at the site of infection. High molecular mass DNA is itself extremely viscous and increases substantially the viscosity of the respiratory mucus ...
Effects of Molecular Crowding on Binding Affinity of Dihydrofolate to
... DHFR is not only found in mammals, but also in bacteria. One isoform is the R67 DHFR, which is carried by an R-plasmid or resistance plasmid. In comparison to the chromosomal DHFR, R67 has different characteristics. For instance, R67 DHFR has a lower affinity for DHF than the chromosomal form 1. Ad ...
... DHFR is not only found in mammals, but also in bacteria. One isoform is the R67 DHFR, which is carried by an R-plasmid or resistance plasmid. In comparison to the chromosomal DHFR, R67 has different characteristics. For instance, R67 DHFR has a lower affinity for DHF than the chromosomal form 1. Ad ...
AMP-forming acetyl-CoA synthetases in Archaea show
... 150 mM KCl and the column was developed at a flow rate of 0.5 mlmin –1. The subunit molecular mass of each enzyme was determined by SDS-PAGE and was in agreement with the predicted size based on the deduced amino acid sequence. Enzymatic assays for ACS activity Enzymatic activity was determined by m ...
... 150 mM KCl and the column was developed at a flow rate of 0.5 mlmin –1. The subunit molecular mass of each enzyme was determined by SDS-PAGE and was in agreement with the predicted size based on the deduced amino acid sequence. Enzymatic assays for ACS activity Enzymatic activity was determined by m ...
Two Arabidopsis Genes (IPMS1 and IPMS2
... (Leu) biosynthesis, an aldol-type condensation of acetyl-coenzyme A (CoA) and 2-oxoisovalerate yielding isopropylmalate. Most biochemical properties of IPMS1 and IPMS2 are similar: broad pH optimum around pH 8.5, Mg21 as cofactor, feedback inhibition by Leu, Km for 2-oxoisovalerate of approximately ...
... (Leu) biosynthesis, an aldol-type condensation of acetyl-coenzyme A (CoA) and 2-oxoisovalerate yielding isopropylmalate. Most biochemical properties of IPMS1 and IPMS2 are similar: broad pH optimum around pH 8.5, Mg21 as cofactor, feedback inhibition by Leu, Km for 2-oxoisovalerate of approximately ...
Reaction Mechanisms of Mononuclear Non
... not all hydroxylases operate via activation of dioxygen. Some such as lipoxygenases and intradiol dioxygenases activate the substrate toward attack by triplet oxygen. The relationship between the choice of metal ligands and mode of enzymatic activation (oxygen versus substrate) will be highlighted t ...
... not all hydroxylases operate via activation of dioxygen. Some such as lipoxygenases and intradiol dioxygenases activate the substrate toward attack by triplet oxygen. The relationship between the choice of metal ligands and mode of enzymatic activation (oxygen versus substrate) will be highlighted t ...
Enzyme Kinetics and Mechanisms
... 4. In the second reaction, the imidazole catalyst is actually part of the substrate that is being hydrolyzed. Therefore, the rate of hydrolysis is dependent only on the substrate, and therefore proceeds with a First Order Rate Constant of 839 min-1. 5. Rate constants of different order cannot be com ...
... 4. In the second reaction, the imidazole catalyst is actually part of the substrate that is being hydrolyzed. Therefore, the rate of hydrolysis is dependent only on the substrate, and therefore proceeds with a First Order Rate Constant of 839 min-1. 5. Rate constants of different order cannot be com ...
Stereochemical imperative in enzymic decarboxylations
... principles of protein structure and catalysis and their role in adaptation and evolution. An important theme in recent work of ours and others is to explore how the stereochemical details of enzymic reactions might reflect underlying catalytic and structural principles that explain in evolutionary t ...
... principles of protein structure and catalysis and their role in adaptation and evolution. An important theme in recent work of ours and others is to explore how the stereochemical details of enzymic reactions might reflect underlying catalytic and structural principles that explain in evolutionary t ...
Probing the active site of homoserine trans
... activation of homoserine via a succinylation reaction. The in vivo activity of this enzyme is subject to tight regulation by several mechanisms, including repression and activation of gene expression, feedback inhibition, temperature regulation and proteolysis. This complex regulation reflects the ke ...
... activation of homoserine via a succinylation reaction. The in vivo activity of this enzyme is subject to tight regulation by several mechanisms, including repression and activation of gene expression, feedback inhibition, temperature regulation and proteolysis. This complex regulation reflects the ke ...
Proteases - Home - KSU Faculty Member websites
... – Ubiquitin/proteasome pathway: First conjugated to multiple molecule of the polypeptide ubiquitin. This modification marks them for rapid hydrolysis by the proteasome in the presence of ATP. – Lysosome pathway: Proteins are transferred into lysosomes which contain proteases that completely digests ...
... – Ubiquitin/proteasome pathway: First conjugated to multiple molecule of the polypeptide ubiquitin. This modification marks them for rapid hydrolysis by the proteasome in the presence of ATP. – Lysosome pathway: Proteins are transferred into lysosomes which contain proteases that completely digests ...
Malate Dehydrogenases – Structure and Function
... MDHs, similar to LDHs, catalyze the conversion of 2-hydroxy acids to the corresponding 2-keto acids (Banaszak and Bradshaw 1975; Birktoft et al. 1982), but MDHs are specific for oxaloacetate and LDH for pyruvate substrate. It is known from kinetic studies that the malate to oxaloacetate reaction is ...
... MDHs, similar to LDHs, catalyze the conversion of 2-hydroxy acids to the corresponding 2-keto acids (Banaszak and Bradshaw 1975; Birktoft et al. 1982), but MDHs are specific for oxaloacetate and LDH for pyruvate substrate. It is known from kinetic studies that the malate to oxaloacetate reaction is ...
A Genetic Defect in Amino Acid Metabolism: Phenylketonuria (PKU)
... Melanin is a brown pigment that affect the colour of our skin, hair and eyes. A child with PKU, PAH is not working properly. This means that phenylalanine cannot be broken-down and its level in blood gets very high. On the other hand, Tyrosine levels tend to be low. It consequences melanin cannot b ...
... Melanin is a brown pigment that affect the colour of our skin, hair and eyes. A child with PKU, PAH is not working properly. This means that phenylalanine cannot be broken-down and its level in blood gets very high. On the other hand, Tyrosine levels tend to be low. It consequences melanin cannot b ...
Protein-Reactive Natural Products
... Nature engages protein targets with reactive small molecules in many ways, and the number of natural products that covalently modify proteins is likely very large. In coming to grips with this subject, we have chosen to address selected reactive natural products for which the protein targets are wel ...
... Nature engages protein targets with reactive small molecules in many ways, and the number of natural products that covalently modify proteins is likely very large. In coming to grips with this subject, we have chosen to address selected reactive natural products for which the protein targets are wel ...
Metabolic implications of methionine excess. Effects of
... Based on the stereospecificity (de Billy et at., 1975) and the quaternary structure (Deme et al., 1972) of the enzyme, it is easy to imagine how complicated its regulation by direct or allosteric substrates might be. We conclude that in adapted rats, the dietary factors used here (methionine and hig ...
... Based on the stereospecificity (de Billy et at., 1975) and the quaternary structure (Deme et al., 1972) of the enzyme, it is easy to imagine how complicated its regulation by direct or allosteric substrates might be. We conclude that in adapted rats, the dietary factors used here (methionine and hig ...
10.25-11.3.11 Glycolysis
... state conditions. We have much more ATP than would be dictated by equilibrium; the ratio of ATP to ADP+Pi in some cells is as high as 200/1 rather than 1/200,000. •This means that a cell can be far from equilibrium w.r. to this ratio, and now, through metabolism, we are going to make EVEN ...
... state conditions. We have much more ATP than would be dictated by equilibrium; the ratio of ATP to ADP+Pi in some cells is as high as 200/1 rather than 1/200,000. •This means that a cell can be far from equilibrium w.r. to this ratio, and now, through metabolism, we are going to make EVEN ...
1 Chapter 1 Chemistry On The Pyrimidine Ring
... The general mechanism for both of these enzymes first involves a sulfur transfer from a donor such as IscS for ThiI, and TusE for MnmA. This yields a protein persulfide intermediate. The enzymes then bind the tRNA and activates the uridine oxygen using ATP to form an adenylated intermediate. The su ...
... The general mechanism for both of these enzymes first involves a sulfur transfer from a donor such as IscS for ThiI, and TusE for MnmA. This yields a protein persulfide intermediate. The enzymes then bind the tRNA and activates the uridine oxygen using ATP to form an adenylated intermediate. The su ...
Vitamins and Coenzymes - Rose
... uptake and synthesis). Nicotinic acid (but not nicotinamide) reduces release of free fatty acids from adipose tissue, probably via binding to a receptor that also binds hydroxycarboxylic acids, and has been used to reduce plasma cholesterol. However, some individuals cannot tolerate the high levels ...
... uptake and synthesis). Nicotinic acid (but not nicotinamide) reduces release of free fatty acids from adipose tissue, probably via binding to a receptor that also binds hydroxycarboxylic acids, and has been used to reduce plasma cholesterol. However, some individuals cannot tolerate the high levels ...
Enzymatic Protein Deglycosylation Kit (EDEGLY)
... Hydrazinolysis of glycoproteins,2 although capable of removing both N-linked and O-linked sugars, results in the complete destruction of the protein component and is, therefore, not suitable if recovery of the protein is desirable. Milder chemical methods such as trifluoromethanesulfonic acid (TFMS) ...
... Hydrazinolysis of glycoproteins,2 although capable of removing both N-linked and O-linked sugars, results in the complete destruction of the protein component and is, therefore, not suitable if recovery of the protein is desirable. Milder chemical methods such as trifluoromethanesulfonic acid (TFMS) ...
Enzyme Mechanisms
... unrelated settings Subtilisin: externals very different from mammalian serine proteases; triad same ...
... unrelated settings Subtilisin: externals very different from mammalian serine proteases; triad same ...
2. Glucogenic amino acids
... Gluconeogenesis and glycolysis are reciprocally regulated so that one pathway is relatively inactive when the other is active. Pyruvate Carboxylase It is an allosteric enzyme. Acetyl CoA is an activator of Pyruvate carboxylase so that generation of oxaloacetate is favored when acetyl CoA level is ...
... Gluconeogenesis and glycolysis are reciprocally regulated so that one pathway is relatively inactive when the other is active. Pyruvate Carboxylase It is an allosteric enzyme. Acetyl CoA is an activator of Pyruvate carboxylase so that generation of oxaloacetate is favored when acetyl CoA level is ...
A 5000-Fold Increase in the Specificity of a Bacterial
... and are efficient enzymes with broad substrate ranges. The turnover rate of PTEAr for the common organophosphorous insecticide malathion is lower than expected based on its physical properties; principally the pka of its leaving group. In this study, we rationalise the turnover rate of PTEAr for mal ...
... and are efficient enzymes with broad substrate ranges. The turnover rate of PTEAr for the common organophosphorous insecticide malathion is lower than expected based on its physical properties; principally the pka of its leaving group. In this study, we rationalise the turnover rate of PTEAr for mal ...
UvA-DARE (Digital Academic Repository) Bacterial class A acid
... Phosphate prodrugs have been successfully utilized to overcome a variety of drug delivery problems that might otherwise have compromised the therapeutic utilities of the parent drug.[11] The ionic nature of the phosphate group in these prodrugs may significantly improve the solubility and dissolutio ...
... Phosphate prodrugs have been successfully utilized to overcome a variety of drug delivery problems that might otherwise have compromised the therapeutic utilities of the parent drug.[11] The ionic nature of the phosphate group in these prodrugs may significantly improve the solubility and dissolutio ...
Annotation guidelines - Systems Biology and Bioinformatics
... GP means gene and protein that reside within organism. This also includes: Gene: genetic sequences reside on DNA that code for mRNA or protein. Protein: A long chain amino acid. Enzyme: Subset of protein that has catalytic function. mRNA: Polypeptide of ribonucleotides. We only restrict to find mRNA ...
... GP means gene and protein that reside within organism. This also includes: Gene: genetic sequences reside on DNA that code for mRNA or protein. Protein: A long chain amino acid. Enzyme: Subset of protein that has catalytic function. mRNA: Polypeptide of ribonucleotides. We only restrict to find mRNA ...
Pyruvate Oxidation Overview of pyruvate metabolism - Rose
... possible for the pyruvate concentration inside the mitochondria to be higher than outside. The energy for the pump comes from a proton gradient, in which the proton concentration outside the mitochondria is higher than it is inside. Many other molecules are present only on one side of the membrane, ...
... possible for the pyruvate concentration inside the mitochondria to be higher than outside. The energy for the pump comes from a proton gradient, in which the proton concentration outside the mitochondria is higher than it is inside. Many other molecules are present only on one side of the membrane, ...
General base-general acid catalysis by terpenoid cyclases
... in all respects18 and ultimately led to the first crystal structure determination of a bacterial terpenoid cyclase.19 The enzyme active site was found to be predominantly nonpolar, consistent with the accommodation of the lipophilic substrate. Even so, a single polar residue was observed near the mou ...
... in all respects18 and ultimately led to the first crystal structure determination of a bacterial terpenoid cyclase.19 The enzyme active site was found to be predominantly nonpolar, consistent with the accommodation of the lipophilic substrate. Even so, a single polar residue was observed near the mou ...
The Tricarboxylic Acid Cycle in Thiobacillus
... Our results further substantiate the hypothesis that in most of the autotrophic organisms the tricarboxylic acid cycle is incomplete. In agreement with Taylor, Hoare & Hoare (I 969) we were unable to detect the a-ketoglutarate dehydrogenase in Thiobacillus denitrijicans. We also failed to demonstrat ...
... Our results further substantiate the hypothesis that in most of the autotrophic organisms the tricarboxylic acid cycle is incomplete. In agreement with Taylor, Hoare & Hoare (I 969) we were unable to detect the a-ketoglutarate dehydrogenase in Thiobacillus denitrijicans. We also failed to demonstrat ...
Enzyme inhibitor
An enzyme inhibitor is a molecule that binds to an enzyme and decreases its activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used in pesticides. Not all molecules that bind to enzymes are inhibitors; enzyme activators bind to enzymes and increase their enzymatic activity, while enzyme substrates bind and are converted to products in the normal catalytic cycle of the enzyme.The binding of an inhibitor can stop a substrate from entering the enzyme's active site and/or hinder the enzyme from catalyzing its reaction. Inhibitor binding is either reversible or irreversible. Irreversible inhibitors usually react with the enzyme and change it chemically (e.g. via covalent bond formation). These inhibitors modify key amino acid residues needed for enzymatic activity. In contrast, reversible inhibitors bind non-covalently and different types of inhibition are produced depending on whether these inhibitors bind to the enzyme, the enzyme-substrate complex, or both.Many drug molecules are enzyme inhibitors, so their discovery and improvement is an active area of research in biochemistry and pharmacology. A medicinal enzyme inhibitor is often judged by its specificity (its lack of binding to other proteins) and its potency (its dissociation constant, which indicates the concentration needed to inhibit the enzyme). A high specificity and potency ensure that a drug will have few side effects and thus low toxicity.Enzyme inhibitors also occur naturally and are involved in the regulation of metabolism. For example, enzymes in a metabolic pathway can be inhibited by downstream products. This type of negative feedback slows the production line when products begin to build up and is an important way to maintain homeostasis in a cell. Other cellular enzyme inhibitors are proteins that specifically bind to and inhibit an enzyme target. This can help control enzymes that may be damaging to a cell, like proteases or nucleases. A well-characterised example of this is the ribonuclease inhibitor, which binds to ribonucleases in one of the tightest known protein–protein interactions. Natural enzyme inhibitors can also be poisons and are used as defences against predators or as ways of killing prey.