endoplasmic reticulum stress and lipid metabolism
... vesicles and transported from the ER to the Golgi where SCAP is cleaved by site-‐1 and site-‐2 proteases to release the active SREBP transcription factor into the cytosol for subsequent translocat ...
... vesicles and transported from the ER to the Golgi where SCAP is cleaved by site-‐1 and site-‐2 proteases to release the active SREBP transcription factor into the cytosol for subsequent translocat ...
Enzyme Specificity and Selectivity
... Enzyme active sites are complementary to the transition state of the reaction While the lock and key analogy is useful for understanding enzyme–substrate interactions, it is important to remember that an enzyme active site is not simply complementary to the substrate. Such an enzyme would merely sta ...
... Enzyme active sites are complementary to the transition state of the reaction While the lock and key analogy is useful for understanding enzyme–substrate interactions, it is important to remember that an enzyme active site is not simply complementary to the substrate. Such an enzyme would merely sta ...
BCHEM 253 – METABOLISM IN HEALTH AND DISEASES
... The isozyme glucokinase catalyzes the same reaction but has a very high Km for glucose of 10.0 mM. This enzyme is not allosterically regulated by high glucose -6phosphate concentrations. The high Km, means that glucokinase only becomes metabolically important when glucose levels are high. This enzym ...
... The isozyme glucokinase catalyzes the same reaction but has a very high Km for glucose of 10.0 mM. This enzyme is not allosterically regulated by high glucose -6phosphate concentrations. The high Km, means that glucokinase only becomes metabolically important when glucose levels are high. This enzym ...
Enzymes lII: Clinical Applications
... measuring the rate of the enzyme-catalyzed chemical reaction. The initial rate of an enzymatic reaction is directly proportional to the amount of enzyme present when the substrate concentrations are maintained at saturating levels (i.e., zero-order kinetics with respect to substrate concentration) a ...
... measuring the rate of the enzyme-catalyzed chemical reaction. The initial rate of an enzymatic reaction is directly proportional to the amount of enzyme present when the substrate concentrations are maintained at saturating levels (i.e., zero-order kinetics with respect to substrate concentration) a ...
as a PDF
... eight major phosphopeptides. Phosphoamino acid analysis together with sequential manual Edman degradation and protein sequence analysis further revealed that, in addition to Ser 235 and Ser 404 , heparin generated Thr 2' 2 , Thr 231 , Ser 262 , Ser 324 , and Ser 35s , the five extra phosphorylation ...
... eight major phosphopeptides. Phosphoamino acid analysis together with sequential manual Edman degradation and protein sequence analysis further revealed that, in addition to Ser 235 and Ser 404 , heparin generated Thr 2' 2 , Thr 231 , Ser 262 , Ser 324 , and Ser 35s , the five extra phosphorylation ...
Increasing the thermostability of sucrose
... (Goedl et al., 2010). For example, an exceptionally efficient process for the regioselective glucosylation of glycerol has recently been developed (Goedl et al., 2008a). The product is a moisturising agent for cosmetics and is commercially available under the trade name Glycoin. For industrial appli ...
... (Goedl et al., 2010). For example, an exceptionally efficient process for the regioselective glucosylation of glycerol has recently been developed (Goedl et al., 2008a). The product is a moisturising agent for cosmetics and is commercially available under the trade name Glycoin. For industrial appli ...
Glyceraldehyde-3-Phosphate Dehydrogenase Is a GABAA Receptor
... (Invitrogen, San Diego, CA), between the polylinker EcoR1 and XhoI sites. Mutagenesis of I2␣1 (T337A and S416G double mutant) was performed by PCR on the I2␣1 recombinant plasmid with the primers 5⬘CGGAATTCAACTATTTCGCCAAGAGAGG-3⬘ and 5⬘-CGCTCGAGTCATCGGTCGATTTTGCCGACGCTG-3⬘, then reinserted in the sa ...
... (Invitrogen, San Diego, CA), between the polylinker EcoR1 and XhoI sites. Mutagenesis of I2␣1 (T337A and S416G double mutant) was performed by PCR on the I2␣1 recombinant plasmid with the primers 5⬘CGGAATTCAACTATTTCGCCAAGAGAGG-3⬘ and 5⬘-CGCTCGAGTCATCGGTCGATTTTGCCGACGCTG-3⬘, then reinserted in the sa ...
Lecture 2 - cholesterol _CVS block
... • Two proteases cleave SREBP to a soluble fragment that enters the nucleus and binds SRE • HMG CoA gene transcription is activated ...
... • Two proteases cleave SREBP to a soluble fragment that enters the nucleus and binds SRE • HMG CoA gene transcription is activated ...
Proteases of Senescing Oat Leaves
... Kinetics. In the particular case of proteolytic enzymes, Lineweaver-Burk plots and determinations of Km values can be complicated, since if some protein substrate is introduced as an impurity, then even in the absence of hemoglobin or other added substrate some proteolysis occurs. This is a more ser ...
... Kinetics. In the particular case of proteolytic enzymes, Lineweaver-Burk plots and determinations of Km values can be complicated, since if some protein substrate is introduced as an impurity, then even in the absence of hemoglobin or other added substrate some proteolysis occurs. This is a more ser ...
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 ...
Enzymes
... • This is the temperature at which the enzyme catalyzes the largest number of reactions per second. • The optimum temperature of enzymes varies in different organisms, and is often but not always close to the temperature at which the enzyme usually functions. • Some enzymes may have very high or ver ...
... • This is the temperature at which the enzyme catalyzes the largest number of reactions per second. • The optimum temperature of enzymes varies in different organisms, and is often but not always close to the temperature at which the enzyme usually functions. • Some enzymes may have very high or ver ...
Carbohydrate metabolism
... 1. Glc enters into hepatic tissue and it is phosphorylated by enzyme glucokinase Glc-6-P. 2. Glc-6-P is converted to Glc-1-P by phosphoglucomutase (isomeration). 3. Glc-1-P is activated with UTP to form UDP-glucose by glucose-1-phosphate uridylyltransferase. This reaction generates UDP-glucose = " ...
... 1. Glc enters into hepatic tissue and it is phosphorylated by enzyme glucokinase Glc-6-P. 2. Glc-6-P is converted to Glc-1-P by phosphoglucomutase (isomeration). 3. Glc-1-P is activated with UTP to form UDP-glucose by glucose-1-phosphate uridylyltransferase. This reaction generates UDP-glucose = " ...
Structure and function of the chloroplast signal recognition particle
... formation with cpSRP. By analogy, with the co-translational targeting system where binding of cytosolic SRP54 to a substrate protein is mediated via its hydrophobic signal sequence, it was shown that a hydrophobic domain within LHCP is required for the post-translational binding to cpSRP (DeLille et ...
... formation with cpSRP. By analogy, with the co-translational targeting system where binding of cytosolic SRP54 to a substrate protein is mediated via its hydrophobic signal sequence, it was shown that a hydrophobic domain within LHCP is required for the post-translational binding to cpSRP (DeLille et ...
Enzymes - Coleg y Cymoedd Moodle
... Easy to measure rate if one of the products if it is a gas. Not always easy though. E.g. looking rate at which amylase breaks down the substrate starch to the product maltose. Both are colourless. Could measure rate starch is used up. Take samples at known times and test with iodine. Could use a co ...
... Easy to measure rate if one of the products if it is a gas. Not always easy though. E.g. looking rate at which amylase breaks down the substrate starch to the product maltose. Both are colourless. Could measure rate starch is used up. Take samples at known times and test with iodine. Could use a co ...
A decrease in cellular energy status stimulates PERK
... kinase; IRE1, inositol requiring enzyme 1; KRB, Krebs–Ringer bicarbonate buffer; tRNAi Met , methionyl initiator tRNA; mGCN2, mammalian orthologue of the yeast GCN2 (general control non-derepressible 2) protein kinase; MIN6, mouse insulinoma cell line 6; PKR, protein kinase RNA activated; PERK, PKR- ...
... kinase; IRE1, inositol requiring enzyme 1; KRB, Krebs–Ringer bicarbonate buffer; tRNAi Met , methionyl initiator tRNA; mGCN2, mammalian orthologue of the yeast GCN2 (general control non-derepressible 2) protein kinase; MIN6, mouse insulinoma cell line 6; PKR, protein kinase RNA activated; PERK, PKR- ...
Enzymes | Principles of Biology from Nature Education
... movement) of the substrate molecules, increasing the number of collisions between substrates and enzymes. Also, increased vibrations in the bonds of the substrates reduce their stability, making them more likely to break. Thus, raising temperature generally increases the reaction rate. However, if t ...
... movement) of the substrate molecules, increasing the number of collisions between substrates and enzymes. Also, increased vibrations in the bonds of the substrates reduce their stability, making them more likely to break. Thus, raising temperature generally increases the reaction rate. However, if t ...
Nutritional Control of Growth and Development in Yeast
... simply by activating this pathway. Similarly, blocking signaling through the pathway concurrent with glucose addition eliminates most, albeit not all, of the responses. Thus, the PKA pathway is both necessary and sufficient for a majority of the transcriptional responses of the cell to glucose (Zama ...
... simply by activating this pathway. Similarly, blocking signaling through the pathway concurrent with glucose addition eliminates most, albeit not all, of the responses. Thus, the PKA pathway is both necessary and sufficient for a majority of the transcriptional responses of the cell to glucose (Zama ...
MICROBIAL PHYSIOLOGY AND BIOCHEMISTRY
... significant only when multiple substrate atoms come in very close vicinity to multiple enzyme atoms. 2. Usually binding sites on enzymes are in form of “gaps” or “clefts” or “crevices”, i.e. some kind of three dimensional structures which have vacancies for a particular shape to fit into them. These ...
... significant only when multiple substrate atoms come in very close vicinity to multiple enzyme atoms. 2. Usually binding sites on enzymes are in form of “gaps” or “clefts” or “crevices”, i.e. some kind of three dimensional structures which have vacancies for a particular shape to fit into them. These ...
Kinetic Rate Reaction
... This reaction allows the body to store the high energy phosphate in the form of creatine phosphate. Because the enzyme reaction is reversible the energy can quickly be made available to muscles. CK is present in high concentration in skeletal muscle, cardiac muscle, thyroid, prostate, and brain; it ...
... This reaction allows the body to store the high energy phosphate in the form of creatine phosphate. Because the enzyme reaction is reversible the energy can quickly be made available to muscles. CK is present in high concentration in skeletal muscle, cardiac muscle, thyroid, prostate, and brain; it ...
Glycolysis and the Catabolism of Hexoses
... • The study of glucose degradation has a rich history in biochemistry (especially for enzymology). • Glucose is first converted into two three-carbon pyruvates via the ten-step glycolysis pathway without directly consuming O2 and with a net production of two ATP molecules by substrate-level phosphor ...
... • The study of glucose degradation has a rich history in biochemistry (especially for enzymology). • Glucose is first converted into two three-carbon pyruvates via the ten-step glycolysis pathway without directly consuming O2 and with a net production of two ATP molecules by substrate-level phosphor ...
Roles of phosphatidate phosphatase enzymes in lipid metabolism
... (Figure 2), including OPI3 [52]. The reduction in PtdOH concentration can be attributed in part to an increase in PtdIns synthesis [52], which draws on the pool of PtdOH through CDP-DAG [12] (Figure 2). The PAH1-encoded PAP1 enzyme also controls the cellular quantities of PtdOH [10], and PAP1 activi ...
... (Figure 2), including OPI3 [52]. The reduction in PtdOH concentration can be attributed in part to an increase in PtdIns synthesis [52], which draws on the pool of PtdOH through CDP-DAG [12] (Figure 2). The PAH1-encoded PAP1 enzyme also controls the cellular quantities of PtdOH [10], and PAP1 activi ...
PROTEIN PHOSPHORYLATION AND CELLULAR REGULATION, I by
... explain them. Eventually, after Neil Madsen found that protamine could physically bind to phosphorylase, which was at least a step in the direction of how it might affect the activity of the enzyme, Cori let me send in my paper. Although, as I have pointed out, knowledge with respect to the properti ...
... explain them. Eventually, after Neil Madsen found that protamine could physically bind to phosphorylase, which was at least a step in the direction of how it might affect the activity of the enzyme, Cori let me send in my paper. Although, as I have pointed out, knowledge with respect to the properti ...
updated ppt slides - UCLA Chemistry and Biochemistry
... a. What assumption must be made about this reaction in order for Km to approach the Kd of the enzyme-substrate complex. b. Briefly define ‘first-order’ as it applies to rate constants (15 words or less). c. Of the rate-constants above, which are first-order? d. Write two different expressions for th ...
... a. What assumption must be made about this reaction in order for Km to approach the Kd of the enzyme-substrate complex. b. Briefly define ‘first-order’ as it applies to rate constants (15 words or less). c. Of the rate-constants above, which are first-order? d. Write two different expressions for th ...
The Calcium-Binding Activity of a Vacuole
... A vacuole membrane-associated calcium-binding protein with an apparent mass of 45 kD was purified from celery (Apium graveolens). This protein, VCaB45, is enriched in highly vacuolate tissues and is located within the lumen of vacuoles. Antigenically related proteins are present in many dicotyledono ...
... A vacuole membrane-associated calcium-binding protein with an apparent mass of 45 kD was purified from celery (Apium graveolens). This protein, VCaB45, is enriched in highly vacuolate tissues and is located within the lumen of vacuoles. Antigenically related proteins are present in many dicotyledono ...
Sequence, expression, and characterization of the first archaeal ATP
... 2.7.1.11) catalyzes the phosphorylation of fructose 6-phosphate (F-6-P) to fructose 1,6-bisphosphate (F-1,6-BP) with ATP as phosphoryl donor. In bacteria and eukarya, ATP-PFKs represent key regulatory enzymes of sugar degradation via the classical Embden-Meyerhof pathway. ATP-PFKs have been characte ...
... 2.7.1.11) catalyzes the phosphorylation of fructose 6-phosphate (F-6-P) to fructose 1,6-bisphosphate (F-1,6-BP) with ATP as phosphoryl donor. In bacteria and eukarya, ATP-PFKs represent key regulatory enzymes of sugar degradation via the classical Embden-Meyerhof pathway. ATP-PFKs have been characte ...
Ultrasensitivity
In molecular biology, ultrasensitivity describes an output response that is more sensitive to stimulus change than the hyperbolic Michaelis-Menten response. Ultrasensitivity is one of the biochemical switches in the cell cycle and has been implicated in a number of important cellular events, including exiting G2 cell cycle arrests in Xenopus laevis oocytes, a stage to which the cell or organism would not want to return.Ultrasensitivity is a cellular system which triggers entry into a different cellular state. Ultrasensitivity gives a small response to first input signal, but an increase in the input signal produces higher and higher levels of output. This acts to filter out noise, as small stimuli and threshold concentrations of the stimulus (input signal) is necessary for the trigger which allows the system to get activated quickly. Ultrasensitive responses are represented by sigmoidal graphs, which resemble cooperativity. Quantification of ultrasensitivity is often approximated by the Hill equation (biochemistry):Response= Stimulus^n/(EC50^n+Stimulus^n)Where Hill's coefficient (n) may represent quantitative measure of ultrasensitive response.