The Ostrich (Struthio camelus) egg
... allowed to settle, and the supernatant, devoid of lytic activity, was discarded. The resin was washed successively with a 0.1 u and 0.4 M ammonium acetate buffer (pH 6.8). The lysozyme was eluted with 1 M ammonium acetate buffer (pH 6.8). After a short dialysis (1 h) against distilled water, the bio ...
... allowed to settle, and the supernatant, devoid of lytic activity, was discarded. The resin was washed successively with a 0.1 u and 0.4 M ammonium acetate buffer (pH 6.8). The lysozyme was eluted with 1 M ammonium acetate buffer (pH 6.8). After a short dialysis (1 h) against distilled water, the bio ...
Regeneration of Cofactors for Enzyme Biocatalysis
... synthesis has been very successful for treatment of cancer and viral diseases such as HIV (Gulick 2003). There are four enzymes commonly employed in the regeneration of ATP from ADP, including the use of phosphoenolpyruvate (PEP) in a coupled reaction catalyzed by pyruvate kinase (PK), acetylphospha ...
... synthesis has been very successful for treatment of cancer and viral diseases such as HIV (Gulick 2003). There are four enzymes commonly employed in the regeneration of ATP from ADP, including the use of phosphoenolpyruvate (PEP) in a coupled reaction catalyzed by pyruvate kinase (PK), acetylphospha ...
Bioretrosynthetic Construction of a Non
... I am appreciative for the positive influence many people have had on my life. I know that any measure of thanks stated here can’t begin to do justice to the amount of gratitude that needs to be expressed, however, I can at least duly recognize many who have helped me along my way. It has been a priv ...
... I am appreciative for the positive influence many people have had on my life. I know that any measure of thanks stated here can’t begin to do justice to the amount of gratitude that needs to be expressed, however, I can at least duly recognize many who have helped me along my way. It has been a priv ...
PDF File - Computational Biochemistry Group
... obtained for the purified protein. A PIR BLAST search produced several hits with Pfl-like proteins of unknown function indicating the decarboxylase was a member of the GRE family. As typical for GREs, an ORF coding the cognate AE (hpdA) was found downstream of the decarboxylase gene (hpdB), at a dis ...
... obtained for the purified protein. A PIR BLAST search produced several hits with Pfl-like proteins of unknown function indicating the decarboxylase was a member of the GRE family. As typical for GREs, an ORF coding the cognate AE (hpdA) was found downstream of the decarboxylase gene (hpdB), at a dis ...
11-Electrophoretic method for the separation of LDH
... reaction is not efficient and pyruvate is preferentially converted to acetyl CoA which enters the citric acid cycle. In order to understand the differences in efficiency of this reaction in skeletal and heart muscle, it is necessary to explore the structure of the LDH enzyme in different tissues of ...
... reaction is not efficient and pyruvate is preferentially converted to acetyl CoA which enters the citric acid cycle. In order to understand the differences in efficiency of this reaction in skeletal and heart muscle, it is necessary to explore the structure of the LDH enzyme in different tissues of ...
Comparative Estimation of Total Protein Content and Enzymatic
... materials contaminated with the egg of this parasite[2]. There are 4 known species of Echinococcus, namely: Echinococcus granulosus, Echinococcus multilocularis, Echinococcus vogeli and Echinococcus oligarthrus. [9]. Three of these species are of medical importance, Echinococcus granulosus, causing ...
... materials contaminated with the egg of this parasite[2]. There are 4 known species of Echinococcus, namely: Echinococcus granulosus, Echinococcus multilocularis, Echinococcus vogeli and Echinococcus oligarthrus. [9]. Three of these species are of medical importance, Echinococcus granulosus, causing ...
The Enolase Superfamily: A General Strategy for Enzyme
... Understanding the role of active site structure in determining both the mechanisms and rates of enzyme-catalyzed reactions is an important problem in enzymology. Until recently, the interdependence of structure, mechanism, and rates has been deduced primarily by examining the structural and catalyti ...
... Understanding the role of active site structure in determining both the mechanisms and rates of enzyme-catalyzed reactions is an important problem in enzymology. Until recently, the interdependence of structure, mechanism, and rates has been deduced primarily by examining the structural and catalyti ...
Modifying the stereochemistry of an enzyme
... Directed evolution can provide a solution to this problem, and molecular biologists have successfully improved the properties of biocatalysts by altering activity (2), substrate specificity (3–5), and stability (6–9). There are two general ways in which the stereoisomeric product of an enzyme-cataly ...
... Directed evolution can provide a solution to this problem, and molecular biologists have successfully improved the properties of biocatalysts by altering activity (2), substrate specificity (3–5), and stability (6–9). There are two general ways in which the stereoisomeric product of an enzyme-cataly ...
Planta
... three inhibitors of aconitase have been identified—fluorocitrate, oxalomalate and citramalate (Bogin and Wallace 1966; Guarrier and Buffa 1969; Adinolfi et al. 1971; Lauble et al. 1996). The inhibition by fluorocitrate and its derivative compounds is well characterized, and the crystal structure of ...
... three inhibitors of aconitase have been identified—fluorocitrate, oxalomalate and citramalate (Bogin and Wallace 1966; Guarrier and Buffa 1969; Adinolfi et al. 1971; Lauble et al. 1996). The inhibition by fluorocitrate and its derivative compounds is well characterized, and the crystal structure of ...
Sites of enzyme activity along the nephron
... respectively (Fig. 2). Thus, succinate dehydrogenase activities in the various portions of the nephron seem to correlate with the calculated number of mitochondna per cell [31]. As expected, the NADP-dependent isocitrate dehydrogenase (ICDI-I) reveals a constant proportion to succinate dehydrogenase ...
... respectively (Fig. 2). Thus, succinate dehydrogenase activities in the various portions of the nephron seem to correlate with the calculated number of mitochondna per cell [31]. As expected, the NADP-dependent isocitrate dehydrogenase (ICDI-I) reveals a constant proportion to succinate dehydrogenase ...
DISCOVERY OF ENZYMES RESPONSIBLE FOR AN ALTERNATE
... inhibited by hymeglusin, a specific inhibitor of bacterial and eukaryotic HMGCS, with experimentally determined Ki of 570 ± 120 nM and kinact of 17 ± 3 min-1. Hymeglusin also prevents the growth of H. volcanii cells in vivo suggesting the essentiality of the enzyme and the mevalonate pathway in the ...
... inhibited by hymeglusin, a specific inhibitor of bacterial and eukaryotic HMGCS, with experimentally determined Ki of 570 ± 120 nM and kinact of 17 ± 3 min-1. Hymeglusin also prevents the growth of H. volcanii cells in vivo suggesting the essentiality of the enzyme and the mevalonate pathway in the ...
glycolysis
... Thus [F-2,6-bisP] , PFK-1 less Phosphofructokinase-2 active, glycolysis is depressed ...
... Thus [F-2,6-bisP] , PFK-1 less Phosphofructokinase-2 active, glycolysis is depressed ...
Membrane Penetration of Cytosolic Phospholipase A2 Is Necessary
... crucial role in maintaining cellular arachidonic acid levels (14). cPLA2 is therefore an attractive target for developing specific inhibitors that can be used as a novel antiinflammatory drugs. cPLA2 binds to membranes in the presence of micromolar Ca2+ via its C2 domain which contains calcium and m ...
... crucial role in maintaining cellular arachidonic acid levels (14). cPLA2 is therefore an attractive target for developing specific inhibitors that can be used as a novel antiinflammatory drugs. cPLA2 binds to membranes in the presence of micromolar Ca2+ via its C2 domain which contains calcium and m ...
Structure, mechanism and function of prenyltransferases
... C120 polymer was found as the final product of an isoprenyl pyrophosphate synthase in plant Arabidopsis thaliana with unknown function [27]. As the cis-prenyltransferases commonly synthesize long-chain products, a unique short-chain cis,trans-FPP is made by Mycobacterium tuberculosis FPPS which utili ...
... C120 polymer was found as the final product of an isoprenyl pyrophosphate synthase in plant Arabidopsis thaliana with unknown function [27]. As the cis-prenyltransferases commonly synthesize long-chain products, a unique short-chain cis,trans-FPP is made by Mycobacterium tuberculosis FPPS which utili ...
Feodor Lynen - Nobel Lecture
... It was possible to assume with fair certainty from these results that the succinic acid produced by yeast from acetate is formed via citric acid7. Sonderhoff’s experiments with deuterated acetic acid led to another important discovery. In the analysis of the yeast cells themselves, it was found that ...
... It was possible to assume with fair certainty from these results that the succinic acid produced by yeast from acetate is formed via citric acid7. Sonderhoff’s experiments with deuterated acetic acid led to another important discovery. In the analysis of the yeast cells themselves, it was found that ...
Antioxidant Enzymes and Function
... same assay as GPx, measure NADPH Other substrates besides GSSG: only mixed disulfides between GSH & γ-glutamylcysteine or CoA ...
... same assay as GPx, measure NADPH Other substrates besides GSSG: only mixed disulfides between GSH & γ-glutamylcysteine or CoA ...
Carbamoyl phosphate synthetase - Department of Biochemistry
... T h e chemical properties of the adduct are consistent with a thioester intermediate. Additional mutations of residues His353 and His312 have implicated these residues in the activation of the thiolate anion and binding of glutamine, respectively [22]. T h e working model for the hydrolysis of gluta ...
... T h e chemical properties of the adduct are consistent with a thioester intermediate. Additional mutations of residues His353 and His312 have implicated these residues in the activation of the thiolate anion and binding of glutamine, respectively [22]. T h e working model for the hydrolysis of gluta ...
41 Purine and Pyrimidine Metabolism
... As has been seen in previous chapters of this text, nucleotides serve numerous functions in different reaction pathways. For example, nucleotides are the activated precursors of DNA and RNA. Nucleotides form the structural moieties of many coenzymes (examples include NADH, FAD, and coenzyme A). Nucl ...
... As has been seen in previous chapters of this text, nucleotides serve numerous functions in different reaction pathways. For example, nucleotides are the activated precursors of DNA and RNA. Nucleotides form the structural moieties of many coenzymes (examples include NADH, FAD, and coenzyme A). Nucl ...
Crystal structure of ATP sulfurylase from Saccharomyces cerevisiae
... (S16±S20), but with a 2-3-1-4-5 topology. This structural classi®cation reveals its close relationship to the superfamily of P-loop-containing nucleotide triphosphate hydrolases and the family of nucleotide kinases, indicating a common evolutionary origin with APS kinase. Typical members of this fam ...
... (S16±S20), but with a 2-3-1-4-5 topology. This structural classi®cation reveals its close relationship to the superfamily of P-loop-containing nucleotide triphosphate hydrolases and the family of nucleotide kinases, indicating a common evolutionary origin with APS kinase. Typical members of this fam ...
Increase of Melanogenesis in the Presence of Fatty Acids
... different slopes that intersects together in a fixed point. Figure 4 shows the doublereciprocal plots of the enzyme activated by fatty acids. ...
... different slopes that intersects together in a fixed point. Figure 4 shows the doublereciprocal plots of the enzyme activated by fatty acids. ...
4-Coumarate:Coenzyme A Ligase Has the Catalytic Capacity to
... ferulate, a very low but detectable amount of p4A was synthesized, accumulating at a 25-fold lower rate than in the presence of ferulate (Fig. 1; Table II). The rates of p4A and p5A synthesis were constant over a time period of at least 40 min when accumulation of radiolabeled products originating f ...
... ferulate, a very low but detectable amount of p4A was synthesized, accumulating at a 25-fold lower rate than in the presence of ferulate (Fig. 1; Table II). The rates of p4A and p5A synthesis were constant over a time period of at least 40 min when accumulation of radiolabeled products originating f ...
Fatty Acid Synthesis in Protozoan Parasites: Unusual Pathways and
... drug targets identified than can be developed with the available resources. The constraints inherent in developing drugs for populations who, at present, cannot pay for treatment raise the bar in terms of deciding which drug targets are worth developing. Not only must a structure or metabolic pathwa ...
... drug targets identified than can be developed with the available resources. The constraints inherent in developing drugs for populations who, at present, cannot pay for treatment raise the bar in terms of deciding which drug targets are worth developing. Not only must a structure or metabolic pathwa ...
ester formation in brewery fermentations
... been named alcohol acetyl transferase (AAT) by Yoshioka & Hashimoto38. However, there are many esters and each differ ...
... been named alcohol acetyl transferase (AAT) by Yoshioka & Hashimoto38. However, there are many esters and each differ ...
Document
... from healthy volunteers and from patients without regard to diet. The blood was anticoagulated with ACD 1; total and differential white blood cell counts, hemoglobin concentration, hematocrit value, and enumeration of erythrocytes, reticulocytes, and platelets were performed on all samples by standa ...
... from healthy volunteers and from patients without regard to diet. The blood was anticoagulated with ACD 1; total and differential white blood cell counts, hemoglobin concentration, hematocrit value, and enumeration of erythrocytes, reticulocytes, and platelets were performed on all samples by standa ...
Inhibitors of HIV-1 Reverse Transcriptase—Associated
... The viral enzyme reverse transcriptase (RT) is essential for replication of the human immunodeficiency virus (HIV), the causative agent of acquired immunodeficiency syndrome (AIDS). HIV RT is multifunctional, with both RNA-dependent and DNA-dependent DNA polymerase activity, as well as ribonuclease ...
... The viral enzyme reverse transcriptase (RT) is essential for replication of the human immunodeficiency virus (HIV), the causative agent of acquired immunodeficiency syndrome (AIDS). HIV RT is multifunctional, with both RNA-dependent and DNA-dependent DNA polymerase activity, as well as ribonuclease ...
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.