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Mikhaylova VV, Eronina TB. Effects of osmolytes under crowding conditions on the properties of muscle glycogen phosphorylase b. Biochimie 2024; 220:48-57. [PMID: 38128775 DOI: 10.1016/j.biochi.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/21/2023] [Accepted: 12/15/2023] [Indexed: 12/23/2023]
Abstract
The study of the relationship between the activity and stability of enzymes under crowding conditions in the presence of osmolytes is important for understanding the functioning of a living cell. The effect of osmolytes (trehalose and betaine) on the secondary and tertiary structure and activity of muscle glycogen phosphorylase b (Phb) under crowding conditions created by PEG 2000 and PEG 20000 was investigated using dynamic light scattering, differential scanning calorimetry, circular dichroism spectroscopy, fluorimetry and enzymatic activity assay. At 25 °C PEGs increased Phb activity, but PEG 20000 to a greater extent. Wherein, PEG 20000 significantly destabilized its tertiary and secondary structure, in contrast to PEG 2000. Trehalose removed the effects of PEGs on Phb, while betaine significantly reduced the activating effect of PEG 20000 without affecting the action of PEG 2000. Under heat stress at 48 °C, the protective effect of osmolytes under crowding conditions was more pronounced than at room temperature, and the Phb activity in the presence of osmolytes was higher in these conditions than in diluted solutions. These results provide important insights into the complex mechanism, by which osmolytes affect the structure and activity of Phb under crowding conditions.
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Affiliation(s)
- Valeriya V Mikhaylova
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, Leninsky pr. 33, Moscow, 119071, Russia.
| | - Tatiana B Eronina
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences, Leninsky pr. 33, Moscow, 119071, Russia
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Eronina TB, Mikhaylova VV, Chebotareva NA, Shubin VV, Kleymenov SY, Kurganov BI. Effect of arginine on stability and aggregation of muscle glycogen phosphorylase b. Int J Biol Macromol 2020; 165:365-374. [PMID: 32961195 DOI: 10.1016/j.ijbiomac.2020.09.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/14/2020] [Accepted: 09/14/2020] [Indexed: 11/26/2022]
Abstract
Arginine (Arg) is frequently used in biotechnology and pharmaceutics to stabilize protein preparations. When using charged ions like Arg, it is necessary to take into account their contribution to the increase in ionic strength, in addition to the effect of Arg on particular processes occurring under the conditions of constancy of ionic strength. Here, we examined contribution of ionic strength (0.15 and 0.5 M) to the effects of Arg on denaturation, thermal inactivation and aggregation of skeletal muscle glycogen phosphorylase b (Phb). Dynamic light scattering, analytical ultracentrifugation, differential scanning calorimetry, circular dichroism and enzymatic activity assay were used to assess the effects of Arg at constant ionic strength compared with the effects of ionic strength alone. We found that high ionic strength did not affect the secondary structure of Phb, but changed conformation of the protein. Such a destabilization of the enzyme causes an increase in the initial rate of aggregation and inactivation of Phb thereby affecting its denaturation. Binding of Arg causes additional changes in the protein conformation, weakening the bonds between monomers in the dimer. This causes the dimer to dissociate into monomers, which rapidly aggregate. Thus, Arg acts on these processes much stronger than just ionic strength.
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Affiliation(s)
- Tatiana B Eronina
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Valeriya V Mikhaylova
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Natalia A Chebotareva
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Vladimir V Shubin
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Sergey Y Kleymenov
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia; Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Vavilova 26, Moscow 119991, Russia
| | - Boris I Kurganov
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia.
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Mikhaylova VV, Eronina TB, Chebotareva NA, Kleymenov SY, Shubin VV, Kurganov BI. A thermal after-effect of UV irradiation of muscle glycogen phosphorylase b. PLoS One 2017; 12:e0189125. [PMID: 29216272 PMCID: PMC5720721 DOI: 10.1371/journal.pone.0189125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 11/20/2017] [Indexed: 01/21/2023] Open
Abstract
Different test systems are used to characterize the anti-aggregation efficiency of molecular chaperone proteins and of low-molecular-weight chemical chaperones. Test systems based on aggregation of UV-irradiated protein are of special interest because they allow studying the protective action of different agents at physiological temperatures. The kinetics of UV-irradiated glycogen phosphorylase b (UV-Phb) from rabbit skeletal muscle was studied at 37°C using dynamic light scattering in a wide range of protein concentrations. It has been shown that the order of aggregation with respect to the protein is equal to unity. A conclusion has been made that the rate-limiting stage of the overall process of aggregation is heat-induced structural reorganization of a UV-Phb molecule, which contains concealed damage.
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Affiliation(s)
- Valeriya V. Mikhaylova
- Department of Structural Biochemistry of Proteins, Bach Institute of Biochemistry, Federal State Institution “Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences”, Moscow, Russia
- * E-mail: (VVM); (BIK)
| | - Tatiana B. Eronina
- Department of Structural Biochemistry of Proteins, Bach Institute of Biochemistry, Federal State Institution “Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences”, Moscow, Russia
| | - Natalia A. Chebotareva
- Department of Structural Biochemistry of Proteins, Bach Institute of Biochemistry, Federal State Institution “Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences”, Moscow, Russia
| | - Sergey Yu. Kleymenov
- Department of Structural Biochemistry of Proteins, Bach Institute of Biochemistry, Federal State Institution “Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences”, Moscow, Russia
- Kol’tsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Vladimir V. Shubin
- Department of Structural Biochemistry of Proteins, Bach Institute of Biochemistry, Federal State Institution “Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences”, Moscow, Russia
| | - Boris I. Kurganov
- Department of Structural Biochemistry of Proteins, Bach Institute of Biochemistry, Federal State Institution “Federal Research Centre “Fundamentals of Biotechnology” of the Russian Academy of Sciences”, Moscow, Russia
- * E-mail: (VVM); (BIK)
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An In Vitro Enzyme System for the Production of myo-Inositol from Starch. Appl Environ Microbiol 2017; 83:AEM.00550-17. [PMID: 28600316 DOI: 10.1128/aem.00550-17] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 05/29/2017] [Indexed: 02/02/2023] Open
Abstract
We developed an in vitro enzyme system to produce myo-inositol from starch. Four enzymes were used, maltodextrin phosphorylase (MalP), phosphoglucomutase (PGM), myo-inositol-3-phosphate synthase (MIPS), and inositol monophosphatase (IMPase). The enzymes were thermostable: MalP and PGM from the hyperthermophilic archaeon Thermococcus kodakarensis, MIPS from the hyperthermophilic archaeon Archaeoglobus fulgidus, and IMPase from the hyperthermophilic bacterium Thermotoga maritima The enzymes were individually produced in Escherichia coli and partially purified by subjecting cell extracts to heat treatment and removing denatured proteins. The four enzyme samples were incubated at 90°C with amylose, phosphate, and NAD+, resulting in the production of myo-inositol with a yield of over 90% at 2 h. The effects of varying the concentrations of reaction components were examined. When the system volume was increased and NAD+ was added every 2 h, we observed the production of 2.9 g myo-inositol from 2.9 g amylose after 7 h, achieving gram-scale production with a molar conversion of approximately 96%. We further integrated the pullulanase from T. maritima into the system and observed myo-inositol production from soluble starch and raw potato with yields of 73% and 57 to 61%, respectively.IMPORTANCEmyo-Inositol is an important nutrient for human health and provides a wide variety of benefits as a dietary supplement. This study demonstrates an alternative method to produce myo-inositol from starch with an in vitro enzyme system using thermostable maltodextrin phosphorylase (MalP), phosphoglucomutase (PGM), myo-inositol-3-phosphate synthase, and myo-inositol monophosphatase. By utilizing MalP and PGM to generate glucose 6-phosphate, we can avoid the addition of phosphate donors such as ATP, the use of which would not be practical for scaled-up production of myo-inositol. myo-Inositol was produced from amylose on the gram scale with yields exceeding 90%. Conversion rates were also high, producing over 2 g of myo-inositol within 4 h in a 200-ml reaction mixture. By adding a thermostable pullulanase, we produced myo-inositol from raw potato with yields of 57 to 61% (wt/wt). The system developed here should provide an attractive alternative to conventional methods that rely on extraction or microbial production of myo-inositol.
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Eronina TB, Mikhaylova VV, Chebotareva NA, Makeeva VF, Kurganov BI. Checking for reversibility of aggregation of UV-irradiated glycogen phosphorylase b under crowding conditions. Int J Biol Macromol 2016; 86:829-39. [DOI: 10.1016/j.ijbiomac.2016.02.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 02/02/2016] [Accepted: 02/02/2016] [Indexed: 12/14/2022]
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Eronina TB, Chebotareva NA, Roman SG, Kleymenov SY, Makeeva VF, Poliansky NB, Muranov KO, Kurganov BI. Thermal denaturation and aggregation of apoform of glycogen phosphorylaseb. Effect of crowding agents and chaperones. Biopolymers 2014; 101:504-16. [DOI: 10.1002/bip.22410] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 09/13/2013] [Indexed: 12/16/2022]
Affiliation(s)
- Tatyana B. Eronina
- Department of Structural Biochemistry of Proteins; A.N. Bach Institute of Biochemistry; Russian Academy of Sciences, Leninsky Prospect 33 Moscow 119071 Russia
| | - Natalia A. Chebotareva
- Department of Structural Biochemistry of Proteins; A.N. Bach Institute of Biochemistry; Russian Academy of Sciences, Leninsky Prospect 33 Moscow 119071 Russia
| | - Svetlana G. Roman
- Department of Structural Biochemistry of Proteins; A.N. Bach Institute of Biochemistry; Russian Academy of Sciences, Leninsky Prospect 33 Moscow 119071 Russia
| | - Sergey Yu. Kleymenov
- Koltsov's Institute of Developmental Biology; Russian Academy of Sciences, Vavilov st 26 Moscow 119334 Russia
| | - Valentina F. Makeeva
- Department of Structural Biochemistry of Proteins; A.N. Bach Institute of Biochemistry; Russian Academy of Sciences, Leninsky Prospect 33 Moscow 119071 Russia
| | - Nikolay B. Poliansky
- Emanuel Institute of Biochemical Physics; Russian Academy of Sciences, Kosygin st. 4 Moscow 119991 Russia
| | - Konstantin O. Muranov
- Emanuel Institute of Biochemical Physics; Russian Academy of Sciences, Kosygin st. 4 Moscow 119991 Russia
| | - Boris I. Kurganov
- Department of Structural Biochemistry of Proteins; A.N. Bach Institute of Biochemistry; Russian Academy of Sciences, Leninsky Prospect 33 Moscow 119071 Russia
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Effect of crowding and chaperones on self-association, aggregation and reconstitution of apophosphorylase b. Int J Biol Macromol 2013; 60:69-76. [DOI: 10.1016/j.ijbiomac.2013.05.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2013] [Revised: 05/14/2013] [Accepted: 05/15/2013] [Indexed: 12/21/2022]
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Roman SG, Chebotareva NA, Eronina TB, Kleymenov SY, Makeeva VF, Poliansky NB, Muranov KO, Kurganov BI. Does the Crowded Cell-like Environment Reduce the Chaperone-like Activity of α-Crystallin? Biochemistry 2011; 50:10607-23. [DOI: 10.1021/bi201030y] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Svetlana G. Roman
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
- Department of Physics, Moscow State University, Leninskie Gory, Moscow 119992, Russia
| | - Natalia A. Chebotareva
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Tatyana B. Eronina
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Sergey Yu. Kleymenov
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
- Kol’tsov Institute of Developmental
Biology, Russian Academy of Sciences, Vavilova
st. 26, Moscow 119991, Russia
| | - Valentina F. Makeeva
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
| | - Nikolay B. Poliansky
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin st. 4, Moscow 119991, Russia
| | - Konstantin O. Muranov
- Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Kosygin st. 4, Moscow 119991, Russia
| | - Boris I. Kurganov
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, Moscow 119071, Russia
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Eronina TB, Chebotareva NA, Kleymenov SY, Roman SG, Makeeva VF, Kurganov BI. Effect of 2-hydroxypropyl-β-cyclodextrin on thermal stability and aggregation of glycogen phosphorylase b from rabbit skeletal muscle. Biopolymers 2010; 93:986-93. [PMID: 20540152 DOI: 10.1002/bip.21508] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The study of the kinetics of thermal aggregation of glycogen phosphorylase b (Phb) from rabbit skeletal muscles by dynamic light scattering at 48°C showed that 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) accelerated the aggregation process and induced the formation of the larger protein aggregates. The reason of the accelerating effect of HP-β-CD is destabilization of the protein molecule under action of HP-β-CD. This conclusion was supported by the data on differential scanning calorimetry and the kinetic data on thermal inactivation of Phb. It is assumed that destabilization of the Phb molecule is due to preferential binding of HP-β-CD to intermediates of protein unfolding in comparison with the original native state. The conclusion regarding the ability of the native Phb for binding of HP-β-CD was substantiated by the data on the enzyme inhibition by HP-β-CD. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 986-993, 2010.
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Affiliation(s)
- Tatyana B Eronina
- Department of Structural Biochemistry of Proteins, A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect 33, Moscow 119071, Russia.
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Eronina TB, Chebotareva NA, Bazhina SG, Kleymenov SY, Naletova IN, Muronetz VI, Kurganov BI. Effect of GroEL on Thermal Aggregation of Glycogen Phosphorylase b
from Rabbit Skeletal Muscle. Macromol Biosci 2010; 10:768-74. [DOI: 10.1002/mabi.200900396] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Eronina TB, Chebotareva NA, Bazhina SG, Makeeva VF, Kleymenov SY, Kurganov BI. Effect of proline on thermal inactivation, denaturation and aggregation of glycogen phosphorylase b from rabbit skeletal muscle. Biophys Chem 2009; 141:66-74. [DOI: 10.1016/j.bpc.2008.12.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 12/22/2008] [Accepted: 12/22/2008] [Indexed: 11/25/2022]
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Meremyanin AV, Eronina TB, Chebotareva NA, Kurganov BI. Kinetics of thermal aggregation of glycogen phosphorylase b from rabbit skeletal muscle: mechanism of protective action of alpha-crystallin. Biopolymers 2008; 89:124-34. [PMID: 17941008 DOI: 10.1002/bip.20872] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The kinetics of thermal aggregation of glycogen phosphorylase b (Phb) from rabbit skeletal muscle have been studied by dynamic light scattering (0.08M Hepes, pH 6.8, containing 0.1M NaCl; 48 degrees C). The hydrodynamic radius of the start aggregates determined from the initial linear parts of the dependences of the hydrodynamic radius (R(h)) on time was found to be 16.7 +/- 1.0 nm. At rather high values of time, the R(h) value for the protein aggregates becomes proportional to t(1/1.8) = t(0.56) suggesting that the aggregation process proceeds in the regime of diffusion-limited cluster-cluster aggregation. In the presence of alpha-crystallin, a protein possessing the chaperone-like activity, the process of protein aggregation switches to the regime of reaction-limited cluster-cluster aggregation as indicated by the exponential dependence of the R(h) value on time. It was shown that the addition of alpha-crystallin raises the rate of thermal inactivation of Phb. These data in combination with the results of the study of interaction of Phb with alpha-crystallin by analytical ultracentrifugation suggest that alpha-crystallin interacts with the intermediates of unfolding of the Phb molecule.
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Affiliation(s)
- Alexey V Meremyanin
- A.N. Bakh Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect 33, 119071 Moscow, Russia.
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Cherepkova OA, Lyutova EM, Eronina TB, Gurvits BY. Chaperone-like activity of macrophage migration inhibitory factor. Int J Biochem Cell Biol 2006; 38:43-55. [PMID: 16099194 DOI: 10.1016/j.biocel.2005.07.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2005] [Revised: 06/23/2005] [Accepted: 07/07/2005] [Indexed: 11/19/2022]
Abstract
Macrophage migration inhibitory factor is a ubiquitous multifunctional cytokine having diverse immunological and neuroendocrine properties. Although this protein is known to be released into the circulation from the secretory granules of anterior pituitary or directly from immune cells as a consequence of stress, its participation in heat stress-induced aggregation of proteins has not yet been reported. We provide here the first evidence that the macrophage migration inhibitory factor possesses chaperone-like properties. It was shown to exist in the form of a mixture of low and high molecular weight oligomers. At heat stress temperatures the large oligomers dissociate into monomers that bind and stabilize thermally denatured malate dehydrogenase and glycogen phosphorylase b and thus prevent aggregation of the model proteins. Similar chaperone-like effects were also observed in the presence of partially purified brain extract containing besides the macrophage migration inhibitory factor a number of ubiquitous hydrophobic low molecular weight proteins identified by N-terminal microsequence analysis. Being highly stable and hydrophobic, the macrophage migration inhibitory factor in combination with other proteins of similar properties may comprise a family of constitutively expressed "small chaperones" that counteract the early onset of stress, around physiological conditions, when heat shock proteins are not abundant.
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Affiliation(s)
- Oxana A Cherepkova
- A.N. Bakh Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect 33, 119071 Moscow, Russia
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Klinov SV, Kurganov BI. Combined kinetic mechanism describing activation and inhibition of muscle glycogen phosphorylase b by adenosine 5'-monophosphate. Biophys Chem 2001; 92:89-102. [PMID: 11527582 DOI: 10.1016/s0301-4622(01)00189-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The kinetic analysis of the glycogen chain growth reaction catalyzed by glycogen phosphorylase b from rabbit skeletal muscle has been carried out over a wide range of concentrations of AMP under the saturation of the enzyme by glycogen. The applicability of 23 different variants of the kinetic model involving the interaction of AMP and glucose 1-phosphate binding sites in the dimeric enzyme molecule is considered. A kinetic model has been proposed which assumes: (i) the independent binding of one molecule of glucose 1-phosphate in the catalytic site on the one hand, and AMP in both allosteric effector sites and both nucleoside inhibitor sites of the dimeric enzyme molecule bound by glycogen on the other hand; (ii) the binding of AMP in one of the allosteric effector sites results in an increase in the affinity of other allosteric effector site to AMP; (iii) the independent binding of AMP to the nucleoside inhibitor sites of the dimeric enzyme molecule; (iv) the exclusive binding of the second molecule of glucose 1-phosphate in the catalytic site of glycogen phosphorylase b containing two molecules of AMP occupying both allosteric effector sites; and (v) the catalytic act occurs exclusively in the complex of the enzyme with glycogen, two molecules of AMP occupying both allosteric effector sites, and two molecules of glucose 1-phosphate occupying both catalytic sites.
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Affiliation(s)
- S V Klinov
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky prospekt, 33, Moscow 117071, Russia.
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Yao Y, Wang MH, Zhao KY, Wang CC. Assay for enzyme activity by following the absorbance change of pH-indicators. JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS 1998; 36:119-30. [PMID: 9711498 DOI: 10.1016/s0165-022x(98)00005-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Based on the absorbance change of indicators with the concentration of hydrogen ion released from an enzyme-catalyzed reaction, a convenient colorimetric method was established for the assay of acidic phospholipase A2 and glycogen phosphorylase b. Brilliant yellow and bromothymol blue were chosen as indicators for assays of acidic phospholipase A2 and glycogen phosphorylase b by following the absorbance changes at 495 and 615 nm, respectively. The method is simple, sample-saving, sensitive and valid for a wide range of enzyme concentrations. It can be extended for assaying other enzymes catalyzing reactions with hydrogen ion concentration changes.
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Affiliation(s)
- Y Yao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, China
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Dombrádi V, Risnik V, Erdödi F, Bot G, Friedrich P. Regulation of phosphorylase kinase in Drosophila melanogaster. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/0020-1790(87)90057-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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