Chapter 9 - Slothnet
... Negative and positive feedback A high concentration of a metabolic product inhibits action of an enzyme in the pathway. Excess product of one pathway can activate an enzyme in another ...
... Negative and positive feedback A high concentration of a metabolic product inhibits action of an enzyme in the pathway. Excess product of one pathway can activate an enzyme in another ...
Enzymes
... Some enzymes require coenzymes • Some enzymes require a coenzyme (another compound) to be bound to them before they can catalyze reactions. • Coenzymes are non-protein organic compounds. • Eg. of coenzymes: Vitamin B complex ...
... Some enzymes require coenzymes • Some enzymes require a coenzyme (another compound) to be bound to them before they can catalyze reactions. • Coenzymes are non-protein organic compounds. • Eg. of coenzymes: Vitamin B complex ...
39 TRANSAMINASE ENZYME ACTIVITIES The α
... d the length of the optical way in [cm] v volume of serum added to the test [ml] Linearity: If the ∆A/min values of samples are higher than 0.150 (340 nm), dilute samples fivefold or tenfold with a ...
... d the length of the optical way in [cm] v volume of serum added to the test [ml] Linearity: If the ∆A/min values of samples are higher than 0.150 (340 nm), dilute samples fivefold or tenfold with a ...
CHAPTER 20 - AMINO ACID METABOLISM Introduction Amino acid
... Amino acid degradation also occurs as a result of normal protein turnover (see Table 201 for half-lives of some enzymes). Proteins, for example, can be damaged and must be replace. Also, controlling the levels (as well as the activities) of enzymes constitutes an important regulatory mechanism. Acco ...
... Amino acid degradation also occurs as a result of normal protein turnover (see Table 201 for half-lives of some enzymes). Proteins, for example, can be damaged and must be replace. Also, controlling the levels (as well as the activities) of enzymes constitutes an important regulatory mechanism. Acco ...
Problem-Set Solutions
... 24.69 Oxaloacetate, an intermediate in the gluconeogenesis conversion of pyruvate to phosphoenolpyruvate, can also act as an intermediate in the first step of the citric acid cycle; oxaloacetate combines with acetyl CoA, which can go directly into the citric acid cycle. 24.70 GTP and ATP 24.71 Lacta ...
... 24.69 Oxaloacetate, an intermediate in the gluconeogenesis conversion of pyruvate to phosphoenolpyruvate, can also act as an intermediate in the first step of the citric acid cycle; oxaloacetate combines with acetyl CoA, which can go directly into the citric acid cycle. 24.70 GTP and ATP 24.71 Lacta ...
Enzymes - Ústav lékařské chemie a biochemie
... zymogenic cells of gastric mucosa located mainly in fundus. The proteolysis proceeds at pH lower than 5 as an intramolecular reaction (autoactivation), or due to active pepsin itself (autocatalysis). At pH higher than 2 the released peptides remain bound to pepsin and act as inhibitors of pepsin act ...
... zymogenic cells of gastric mucosa located mainly in fundus. The proteolysis proceeds at pH lower than 5 as an intramolecular reaction (autoactivation), or due to active pepsin itself (autocatalysis). At pH higher than 2 the released peptides remain bound to pepsin and act as inhibitors of pepsin act ...
Chemical Energy Production
... – loss of electron equivalent to loss of H atom – when molecule loses electrons it becomes OXIDIZED ...
... – loss of electron equivalent to loss of H atom – when molecule loses electrons it becomes OXIDIZED ...
The Synthesis and Degradation of Nucleotides
... Ribonucleotide Reductase has a unique control mechanism to assure that the deoxyribonucleotides are synthesized in adequate and balanced amounts. This enzyme contains an Activity Site, a Specificity Site, and the catalytic site. The Activity Site turns the enzyme “ON” or “OFF”; the Specificity Site ...
... Ribonucleotide Reductase has a unique control mechanism to assure that the deoxyribonucleotides are synthesized in adequate and balanced amounts. This enzyme contains an Activity Site, a Specificity Site, and the catalytic site. The Activity Site turns the enzyme “ON” or “OFF”; the Specificity Site ...
Enzymes - WordPress.com
... of most of their properties: 1. The Active Site • In an enzyme, folding brings together amino acids, most of which are not adjacent in the primary sequence, so that some amino acids form a three-dimensional structure that binds with the substrate to form the enzyme-substrate complex • This complex r ...
... of most of their properties: 1. The Active Site • In an enzyme, folding brings together amino acids, most of which are not adjacent in the primary sequence, so that some amino acids form a three-dimensional structure that binds with the substrate to form the enzyme-substrate complex • This complex r ...
VITAMINS-5
... Vitamin B5 : What’s the role • B5 is an important component of coenzyme A (CoA) • Role of CoA • Required for chemical reactions that generate energy from food (fat, carbohydrates, and proteins) • Synthesis of essential fats, cholesterol, steroid hormones , acetylcholine, melatonin and Heme • Metabo ...
... Vitamin B5 : What’s the role • B5 is an important component of coenzyme A (CoA) • Role of CoA • Required for chemical reactions that generate energy from food (fat, carbohydrates, and proteins) • Synthesis of essential fats, cholesterol, steroid hormones , acetylcholine, melatonin and Heme • Metabo ...
402_06_watersoluble2..
... Symptoms – hemorrhages, lassitude, weight loss, bone weakening, anemia, edema, tooth loss. Biological lesion -- impaired collagen and connective tissue synthesis due to lack of ...
... Symptoms – hemorrhages, lassitude, weight loss, bone weakening, anemia, edema, tooth loss. Biological lesion -- impaired collagen and connective tissue synthesis due to lack of ...
Metabolic regulation of Escherichia coli cultivated under anaerobic
... Reoxidation of the reducing equivalents such as NADH generated by the oxidation of the energy source occurs in the respiratory chain under aerobic or microaerobioc condition. In E. coli, NADH is oxidized in the respiratory chain via a coupled NADH dehydrogenage NDH-1 encoded by nuo or an uncoupled d ...
... Reoxidation of the reducing equivalents such as NADH generated by the oxidation of the energy source occurs in the respiratory chain under aerobic or microaerobioc condition. In E. coli, NADH is oxidized in the respiratory chain via a coupled NADH dehydrogenage NDH-1 encoded by nuo or an uncoupled d ...
MS PowerPoint - Catalysis Eprints database
... • Ionic interactions between an enzyme-bound metal and a substrate help orient the substrate for reaction or stabilize charged reaction transition states. • Metals also mediate oxidation-reduction reactions by reversible changes in the metal ion’s oxidation state. • For example – in hemoglobin Fe in ...
... • Ionic interactions between an enzyme-bound metal and a substrate help orient the substrate for reaction or stabilize charged reaction transition states. • Metals also mediate oxidation-reduction reactions by reversible changes in the metal ion’s oxidation state. • For example – in hemoglobin Fe in ...
PP - Columbia University
... Exception #1: • 1) Water: 55 M (pure water) is considered the “unit” concentration in this case instead of 1M The concentration of water rarely changes during the course of an aqueous reaction, since water is at such a high concentration. • So when calulating Go, instead of writing in “55” when wat ...
... Exception #1: • 1) Water: 55 M (pure water) is considered the “unit” concentration in this case instead of 1M The concentration of water rarely changes during the course of an aqueous reaction, since water is at such a high concentration. • So when calulating Go, instead of writing in “55” when wat ...
Lecture 12-14 (Parker) - Department of Chemistry ::: CALTECH
... Energy charge determines whether glycolysis of gluconeogenesis will be most active The most important regulatory site is the interconversion of fructose 6-phosphate and fructose 1,6-bisphosphate When energy is needed the concentration of AMP will be relatively high. AMP stimulates phosphofructokina ...
... Energy charge determines whether glycolysis of gluconeogenesis will be most active The most important regulatory site is the interconversion of fructose 6-phosphate and fructose 1,6-bisphosphate When energy is needed the concentration of AMP will be relatively high. AMP stimulates phosphofructokina ...
Chapter 14 Glycolysis, Gluconeogenesis, and the Pentose
... Answer Dietary niacin is used to synthesize NAD. Oxidations carried out by NAD are part of cyclic oxidation-reduction processes, with NAD/NADH as an electron carrier. Because of this cycling, one molecule of NAD can oxidize many thousands of molecules of glucose, and thus the dietary requirement ...
... Answer Dietary niacin is used to synthesize NAD. Oxidations carried out by NAD are part of cyclic oxidation-reduction processes, with NAD/NADH as an electron carrier. Because of this cycling, one molecule of NAD can oxidize many thousands of molecules of glucose, and thus the dietary requirement ...
Chapter 21 Lipid Biosynthesis
... The synthesis of fatty acids and their breakdown by oxidation occur by separate pathways. Compare the two paths by filling in the blanks below. (Some blanks may require more than one ...
... The synthesis of fatty acids and their breakdown by oxidation occur by separate pathways. Compare the two paths by filling in the blanks below. (Some blanks may require more than one ...
BIOCHEMISTRY Carbohydrate Metabolism
... • Step 3 – Phosphofructokinase (an allosteric enzyme) is inhibited by high levels of ATP & Citrate & is activated by high levels of ADP. • Step 10 – Pyruvate kinase (an allosteric enzyme) is inhibited by high levels of ATP & Acetyl CoA. ...
... • Step 3 – Phosphofructokinase (an allosteric enzyme) is inhibited by high levels of ATP & Citrate & is activated by high levels of ADP. • Step 10 – Pyruvate kinase (an allosteric enzyme) is inhibited by high levels of ATP & Acetyl CoA. ...
Enzyme - PharmaStreet
... • uncompetitive inhibitors are inhibitors that bind reversibly to an enzyme when the substrate is already bound to the active site. • In other words, the inhibitor binds to the enzyme–substrate complex. In this situation, increasing the substrate concentration will not overcome inhibition. Indeed, ...
... • uncompetitive inhibitors are inhibitors that bind reversibly to an enzyme when the substrate is already bound to the active site. • In other words, the inhibitor binds to the enzyme–substrate complex. In this situation, increasing the substrate concentration will not overcome inhibition. Indeed, ...
Chapter
... • Absolute specificity - the enzyme will catalyze only one reaction. • Group specificity - the enzyme will act only on molecules that have specific functional groups, such as amino, phosphate and methyl groups. • Linkage specificity - the enzyme will act on a particular type of chemical bond regardl ...
... • Absolute specificity - the enzyme will catalyze only one reaction. • Group specificity - the enzyme will act only on molecules that have specific functional groups, such as amino, phosphate and methyl groups. • Linkage specificity - the enzyme will act on a particular type of chemical bond regardl ...
Sample pages 2 PDF
... oxidative, while anabolic reactions are generally reductive. Catabolic enzymes like glucose 6-phosphate dehydrogenase from the Entner-Doudoroff pathway use NAD+ , while the enzyme catalyzing the same reaction in the pentose phosphate pathway uses NADP+ . This is, however, often not true. In E. coli ...
... oxidative, while anabolic reactions are generally reductive. Catabolic enzymes like glucose 6-phosphate dehydrogenase from the Entner-Doudoroff pathway use NAD+ , while the enzyme catalyzing the same reaction in the pentose phosphate pathway uses NADP+ . This is, however, often not true. In E. coli ...
Biosc_48_Chapter_5_lecture
... H+ from the mitochondrial matrix to the space between the inner and outer membranes. b. This sets up a huge concentration gradient of H+ between the membranes. c. H+ can only move through the inner membrane through structures called respiratory assemblies d. Movement of H+ across the membrane provid ...
... H+ from the mitochondrial matrix to the space between the inner and outer membranes. b. This sets up a huge concentration gradient of H+ between the membranes. c. H+ can only move through the inner membrane through structures called respiratory assemblies d. Movement of H+ across the membrane provid ...
(Vitis vinifera L.) berries - Oxford Academic
... 4B) PEPC can be seen in the vasculature, the parenchyma cells of the pericarp and within the developing seeds. Early in seed development PEPC was associated with the inner layer of the outer integument ( Fig. 4B). In an older berry (80 d after full bloom) PEPC was particularly associated with the va ...
... 4B) PEPC can be seen in the vasculature, the parenchyma cells of the pericarp and within the developing seeds. Early in seed development PEPC was associated with the inner layer of the outer integument ( Fig. 4B). In an older berry (80 d after full bloom) PEPC was particularly associated with the va ...
General theory of enzyme action, by Leonor Michaelis and Maud
... serine residues, only one, serine 195, was modified, resulting in a total loss of enzyme activity. This chemical modification reaction suggested that this unusually reactive serine residue plays a central role in the catalytic mechanism of chymotrypsin. ...
... serine residues, only one, serine 195, was modified, resulting in a total loss of enzyme activity. This chemical modification reaction suggested that this unusually reactive serine residue plays a central role in the catalytic mechanism of chymotrypsin. ...
Nicotinamide adenine dinucleotide
Nicotinamide adenine dinucleotide (NAD) is a coenzyme found in all living cells. The compound is a dinucleotide, because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine base and the other nicotinamide. Nicotinamide adenine dinucleotide exists in two forms, an oxidized and reduced form abbreviated as NAD+ and NADH respectively.In metabolism, nicotinamide adenine dinucleotide is involved in redox reactions, carrying electrons from one reaction to another. The coenzyme is, therefore, found in two forms in cells: NAD+ is an oxidizing agent – it accepts electrons from other molecules and becomes reduced. This reaction forms NADH, which can then be used as a reducing agent to donate electrons. These electron transfer reactions are the main function of NAD. However, it is also used in other cellular processes, the most notable one being a substrate of enzymes that add or remove chemical groups from proteins, in posttranslational modifications. Because of the importance of these functions, the enzymes involved in NAD metabolism are targets for drug discovery.In organisms, NAD can be synthesized from simple building-blocks (de novo) from the amino acids tryptophan or aspartic acid. In an alternative fashion, more complex components of the coenzymes are taken up from food as the vitamin called niacin. Similar compounds are released by reactions that break down the structure of NAD. These preformed components then pass through a salvage pathway that recycles them back into the active form. Some NAD is also converted into nicotinamide adenine dinucleotide phosphate (NADP); the chemistry of this related coenzyme is similar to that of NAD, but it has different roles in metabolism.Although NAD+ is written with a superscript plus sign because of the formal charge on a particular nitrogen atom, at physiological pH for the most part it is actually a singly charged anion (charge of minus 1), while NADH is a doubly charged anion.