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Tagirova MA, Eremeev NL, Balabushevich NG, Volodkin DV, Klyachko NL. Preparation of Catalase Cross-Linked Aggregates Based on Vaterite Matrix. APPL BIOCHEM MICRO+ 2022. [DOI: 10.1134/s0003683822080075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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2
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Timoshenko RV, Vaneev AN, Savin NA, Klyachko NL, Parkhomenko YN, Salikhov SV, Majouga AG, Gorelkin PV, Erofeev AS. Promising Approaches for Determination of Copper Ions in Biological Systems. ACTA ACUST UNITED AC 2020. [DOI: 10.1134/s1995078020020196] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Gazaryan IG, Shchedrina VA, Klyachko NL, Zakhariants AA, Kazakov SV, Brown AM. Zinc Switch in Pig Heart Lipoamide Dehydrogenase: Steady-State and Transient Kinetic Studies of the Diaphorase Reaction. Biochemistry (Mosc) 2020; 85:908-919. [PMID: 33045951 DOI: 10.1134/s0006297920080064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Elevation of intracellular Zn2+ following ischemia contributes to cell death by affecting mitochondrial function. Zn2+ is a differential regulator of the mitochondrial enzyme lipoamide dehydrogenase (LADH) at physiological concentrations (Ka = 0.1 µM free zinc), inhibiting lipoamide and accelerating NADH dehydrogenase activities. These differential effects have been attributed to coordination of Zn2+ by LADH active-site cysteines. A detailed kinetic mechanism has now been developed for the diaphorase (NADH-dehydrogenase) reaction catalyzed by pig heart LADH using 2,6-dichlorophenol-indophenol (DCPIP) as a model quinone electron acceptor. Anaerobic stopped-flow experiments show that two-electron reduced LADH is 15-25-fold less active towards DCPIP reduction than four-electron reduced enzyme, or Zn2+-modified reduced LADH (the corresponding values of the rate constants are (6.5 ± 1.5) × 103 M-1·s-1, (9 ± 2) × 104 M-1·s-1, and (1.6 ± 0.5) × 105 M-1·s-1, respectively). Steady-state kinetic studies with different diaphorase substrates show that Zn2+ accelerates reaction rates exclusively for two-electron acceptors (duroquinone, DCPIP), but not for one-electron acceptors (benzoquinone, ubiquinone, ferricyanide). This implies that the two-electron reduced form of LADH, prevalent at low NADH levels, is a poor two-electron donor compared to the four-electron reduced or Zn2+-modified reduced LADH forms. These data suggest that zinc binding to the active-site thiols switches the enzyme from one- to two-electron donor mode. This zinc-activated switch has the potential to alter the ratio of superoxide and H2O2 generated by the LADH oxidase activity.
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Affiliation(s)
- I G Gazaryan
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY 10605, USA.,Department of Chemistry and Physical Sciences, Dyson College of Arts and Sciences, Pace University, Pleasantville, NY 10570, USA.,Department of Chemical Enzymology, Lomonosov Moscow State University, Moscow, 119899, Russia.,Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Moscow, 119071, Russia
| | - V A Shchedrina
- Department of Chemical Enzymology, Lomonosov Moscow State University, Moscow, 119899, Russia
| | - N L Klyachko
- Department of Chemical Enzymology, Lomonosov Moscow State University, Moscow, 119899, Russia.,Derzhavin Tambov State University, Tambov, 392000, Russia
| | - A A Zakhariants
- Bach Institute of Biochemistry, Federal Research Centre "Fundamentals of Biotechnology", Russian Academy of Sciences, Moscow, 119071, Russia.,Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia
| | - S V Kazakov
- Department of Chemistry and Physical Sciences, Dyson College of Arts and Sciences, Pace University, Pleasantville, NY 10570, USA
| | - A M Brown
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY 10605, USA.
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Golovin YI, Zhigachev AO, Efremova MV, Majouga AG, Kabanov AV, Klyachko NL. Ways and Methods for Controlling Biomolecular Structures Using Magnetic Nanoparticles Activated by an Alternating Magnetic Field. ACTA ACUST UNITED AC 2018. [DOI: 10.1134/s1995078018030072] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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5
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Filatova LY, Klyachko NL, Kudryashova EV. Targeted delivery of anti-tuberculosis drugs to macrophages: targeting mannose receptors. Russ Chem Rev 2018. [DOI: 10.1070/rcr4740] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kudryashova EV, Deygen IM, Sukhoverkov KV, Filatova LY, Klyachko NL, Vorobei AM, Pokrovskiy OI, Ustinovich KB, Parenago OO, Antonov EN, Dunaev AG, Krotova LI, Popov VK, Egorov AM. Micronization of levofloxacin by supercritical antisolvent precipitation. Russ J Phys Chem B 2017. [DOI: 10.1134/s1990793116080054] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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7
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Chertkov OV, Armeev GA, Uporov IV, Legotsky SA, Sykilinda NN, Shaytan AK, Klyachko NL, Miroshnikov KA. Dual Active Site in the Endolytic Transglycosylase gp144 of Bacteriophage phiKZ. Acta Naturae 2017. [DOI: 10.32607/20758251-2017-9-1-81-87] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lytic transglycosylases are abundant peptidoglycan lysing enzymes that degrade the heteropolymers of bacterial cell walls in metabolic processes or in the course of a bacteriophage infection. The conventional catalytic mechanism of transglycosylases involves only the Glu or Asp residue. Endolysin gp144 of Pseudomonas aeruginosa bacteriophage phiKZ belongs to the family of Gram-negative transglycosylases with a modular composition and C-terminal location of the catalytic domain. Glu115 of gp144 performs the predicted role of a catalytic residue. However, replacement of this residue does not completely eliminate the activity of the mutant protein. Site-directed mutagenesis has revealed the participation of Tyr197 in the catalytic mechanism, as well as the presence of a second active site involving Glu178 and Tyr147. The existence of the dual active site was supported by computer modeling and monitoring of the molecular dynamics of the changes in the conformation and surface charge distribution as a consequence of point mutations.
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Rudakovskaya PG, Gerasimov VM, Metelkina ON, Beloglazkina EK, Zyk NV, Savchenko AG, Shchetinin IV, Salikhov SV, Abakumov MA, Klyachko NL, Golovin YI, Mazhuga AG. Synthesis and characterization of PEG-silane functionalized iron oxide(II, III) nanoparticles for biomedical application. ACTA ACUST UNITED AC 2015. [DOI: 10.1134/s1995078015060105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Rudakovskaya PG, Beloglazkina EK, Majouga AG, Klyachko NL, Kabanov AV, Zyk NV. Synthesis of magnetite-gold nanoparticles with core-shell structure. ACTA ACUST UNITED AC 2015. [DOI: 10.3103/s0027131415030104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Filatova LY, Donovan DM, Becker SC, Priyma AD, Kabanov AV, Klyachko NL. An investigation of the structure and function of antistaphylococcal endolysins using kinetic methods. ACTA ACUST UNITED AC 2014. [DOI: 10.3103/s0027131414030043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Golovin YI, Klyachko NL, Sokolsky-Papkov M, Kabanov AV. Single-domain magnetic nanoparticles as force generators for the nanomechanical control of biochemical reactions by low-frequency magnetic fields. ACTA ACUST UNITED AC 2013. [DOI: 10.3103/s1062873813110130] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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12
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Pechenkin MA, Balabushevich NG, Zorov IN, Izumrudov VA, Klyachko NL, Kabanov AV, Larionova NI. Use of Protease Inhibitors in Composite Polyelectrolyte Microparticles in Order to Increase the Bioavailability of Perorally Administered Encapsulated Proteins. Pharm Chem J 2013. [DOI: 10.1007/s11094-013-0898-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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13
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Levashov PA, Popov DV, Popova VM, Zhilenkov EL, Morozova OA, Belogurova NG, Sedov SA, Dyatlov IA, Klyachko NL, Levashov AV. Enzymes of SPZ7 phage: isolation and properties. Biochemistry (Mosc) 2010; 75:1160-4. [PMID: 21077836 DOI: 10.1134/s0006297910090105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Bacteriophage enzyme preparations exolysin and endolysin were studied. Exolysin (a phage-associated enzyme) was obtained from tail fraction and endolysin from phage-free cytoplasmic fraction of disintegrated Salmonella enteritidis cells. A new method for purification of these enzymes was developed, and their molecular masses were determined. The main catalytic properties of the studied enzymes (pH optimum and specificity to bacterial substrates) were found to be similar. Both enzymes lyse Escherichia coli cells like chicken egg lysozyme, but more efficiently lyse S. enteritidis cells and cannot lyse Micrococcus luteus, a good substrate for chicken egg lysozyme. Similar properties of exolysin and endolysin suggest that these enzymes are structurally similar or even identical.
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Affiliation(s)
- P A Levashov
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia.
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Filatova LY, Oxenoyt YS, Yakovleva KS, Ivanova NI, Klyachko NL. Investigation of the activity and stability of papain in different micellar systems. ACTA ACUST UNITED AC 2010. [DOI: 10.3103/s0027131410020057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Pshezhetsky AV, Klyachko NL, Levashov AV, Martinek K. Catalysis by Laccase (FromCoriolus uersicolor) in Microheterogeneous Media of the Water/Organic Solvent/Surfactant Type. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10242429008992090] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
| | - N. L. Klyachko
- Chemistry Department, Moscow State University, SU-117234, USSR
| | - A. V. Levashov
- Chemistry Department, Moscow State University, SU-117234, USSR
| | - Karel Martinek
- Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, CS-16610, Prague, Czechoslovakia
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Martinek K, Berezin IV, Khmelnitski YL, Klyachko NL, Levashov AV. Enzymes Entrapped Into Reversed Micelles Of Surfactants In Organic Solvents: Key Trends In Applied Enzymology (Biotechnology). ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10242428709040126] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Karel Martinek
- Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, CS-166 10, Prague, 6, Czechoslovakia
| | - I. V. Berezin
- Chemistry Department, Moscow State University, SU-117 234, Moscow, USSR
| | | | - N. L. Klyachko
- Chemistry Department, Moscow State University, SU-117 234, Moscow, USSR
| | - A. V. Levashov
- Chemistry Department, Moscow State University, SU-117 234, Moscow, USSR
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Klyachko NL, Dmitrieva NF, Eshchina AS, Ignatenko OV, Filatova LY, Rainina EI, Kazarov AK, Levashov AV. Bacteriophage enzymes for the prevention and treatment of bacterial infections: Stability and stabilization of the enzyme lysing Streptococcus pyogenes cells. Russ J Bioorg Chem 2008. [DOI: 10.1134/s1068162008030217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Tikhonova TV, Kurkin SA, Klyachko NL, Popov VO. Use of a reverse micelle system for study of oligomeric structure of NAD+-reducing hydrogenase from Ralstonia eutropha H16. Biochemistry (Mosc) 2005; 70:645-51. [PMID: 16038606 DOI: 10.1007/s10541-005-0164-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Inclusion of an oligomeric enzyme, NAD+-dependent hydrogenase from the hydrogen-oxidizing bacterium Ralstonia eutropha, into a system of reverse micelles of different sizes resulted in its dissociation into catalytically active heterodimers and subunits, which were characterized in reactions with various substrates. It was found that: 1) the native tetrameric form of this enzyme catalyzes all types of studied reactions; 2) hydrogenase dimer, HoxHY, is a minimal structural unit catalyzing hydrogenase reaction with an artificial electron donor, reduced methyl viologen; 3) all structural fragments containing FMN and NAD+/NADH-binding sites exhibit catalytic activity in diaphorase reactions with one- and two-electron acceptors; 4) small subunits, HoxY and HoxU also exhibit activity in diaphorase reactions with artificial acceptors. These results can be considered as indirect evidence that the second FMN molecule may be associated with one of the small subunits (HoxY or HoxU) of the hydrogenase from R. eutropha.
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Affiliation(s)
- T V Tikhonova
- Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky pr. 33, 119071 Moscow, Russia.
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Affiliation(s)
- N L Klyachko
- Timiryazev Institute of Plant Physiology, RAS, Botanicheskaya ul 35, Moscow 127276, Russia
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Smirnov SA, Koroleva OV, Gavrilova VP, Belova AB, Klyachko NL. Laccases from Basidiomycetes: physicochemical characteristics and substrate specificity towards methoxyphenolic compounds. Biochemistry (Mosc) 2001; 66:774-9. [PMID: 11563958 DOI: 10.1023/a:1010216829856] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Laccases from the Basidiomycetes Coriolus hirsutus, Coriolus zonatus, Cerrena maxima, and Coriolisimus fulvocinerea have been isolated and purified to homogeneity and partially characterized. The kinetics of oxidation of different methoxyphenolic compounds by the fungal laccases has been studied. As laccase substrates, such methoxyphenolic compounds as 4-hydroxy-3,5-dimethoxycinnamic acid (sinapinic acid), 4-hydroxy-3-methoxycinnamic acid (ferulic acid), and 2-methoxyphenol (guaiacol) were used. The stoichiometries of the enzymatic reactions were determined: guaiacol and sinapinic acid are one-electron donors and their oxidation apparently results in the formation of dimers. It was established that kcat/Km, which indicates the effectiveness of catalysis, increases in the series guaiacol, ferulic acid, and sinapinic acid. This fact might be connected with the influence of substituents of the phenolic ring of the substrates. This phenomenon was established for fungal laccases with different physicochemical properties, amino acid composition, and carbohydrate content. This suggests that all fungal laccases possess the same mechanism of interaction between organic substrate electron donors and the copper-containing active site of the enzyme and that this interaction determines the observed values of the kinetic parameters.
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Affiliation(s)
- S A Smirnov
- School of Chemistry, Lomonosov Moscow State University, Moscow, 119899, Russia.
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Abstract
We have used the enhanced green fluorescent protein (EGFP) to investigate the properties of surfactant-entrapped water pools in organic solvents (reversed micelles) with steady-state and time-resolved fluorescence methods. The surfactant used was sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and the organic solvents were isooctane and (the more viscous) dodecane, respectively. The water content of the water pools could be controlled through the parameter w0, which is the water-to-surfactant molar ratio. With steady-state fluorescence, it was observed that subtle fluorescence changes could be noted in reversed micelles of different water contents. EGFP can be used as a pH-indicator of the water droplets in reversed micelles. Time-resolved fluorescence methods also revealed subtle changes in fluorescence decay times when the results in bulk water were compared with those in reversed micelles. The average fluorescence lifetimes of EGFP scaled with the relative fluorescence intensities. Time-resolved fluorescence anisotropy of EGFP in aqueous solution and reversed micelles yielded single rotational correlation times. Geometrical considerations could assign the observed correlation times to dehydrated protein at low w0 and internal EGFP rotation within the droplet at the highest w0.
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Affiliation(s)
- M A Uskova
- MicroSpectroscopy Centre, Department of Biomolecular Sciences, Wageningen University, The Netherlands
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Grinshtein SV, Nikolskaya II, Klyachko NL, Levashov AV, Kost OA. Structural organization of membrane and soluble forms of somatic angiotensin-converting enzyme. Biochemistry (Mosc) 1999; 64:571-80. [PMID: 10381620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The catalytic activity and quaternary structure of soluble (s) and membrane (m) forms of angiotensin-converting enzyme (ACE) were studied in reversed micelles of ternary system Aerosol OT--water--octane. The profile of the dependence of the catalytic activity of the two enzyme forms on the degree of surfactant hydration (micellar size) had several optima corresponding to the function of various active oligomeric enzyme forms; the curves for the s- and m-forms of ACE were different. Data of sedimentation analysis prove that in reversed micelles, s-ACE can exist as monomers, dimers, or tetramers depending on the hydration degree, and the m-form is present as dimers and tetramers only. The values of the kinetic parameters for the hydrolysis of the substrate furylacryloyl-Phe-Gly-Gly by all the enzyme forms were determined, and the data indicate that the activity of the m-form is enhanced by oligomerization. The ACE activity strongly depends on the medium; it is higher when ACE is in contact with matrix or other enzyme molecules.
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Affiliation(s)
- S V Grinshtein
- School of Chemistry, Lomonosov Moscow State University, Moscow, 119899, Russia
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Abstract
Malic dehydrogenase (MDH) studied in water and reversed micelles upon pressure application revealed a difference in catalysis. Whereas MDH in water appeared to be not sensitive to the pressure increasing, the catalytic activity of MDH in reversed micelles showed bell-shaped dependencies both on pressure and surfactant hydration degree, w0. The catalytic activity of MDH was found to be maximal under moderate pressure equal to 300-500 bar and at w0 approximately 14 with the difference between lowest and highest levels of the catalytic activity amounted to about 10 times. The work presented demonstrates for the first time the co-operative effect of reversed micelles and pressure application to malic dehydrogenase leading to the enzyme regulation that cannot be realized in aqueous solution.
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Affiliation(s)
- N L Klyachko
- Department of Chemical Enzymology, Faculty of Chemistry, Moscow State University, Moscow, 119899, Russia
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Levashov PA, Muronetz VI, Klyachko NL, Nagradova NK. Catalytically active monomers of E. coli glyceraldehyde-3-phosphate dehydrogenase. J Protein Chem 1998; 17:229-35. [PMID: 9588946 DOI: 10.1023/a:1022580501200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Monomeric forms of E. coli glyceraldehyde-3-phosphate dehydrogenase have been prepared using two different experimental approaches: (1) covalent immobilization of a tetramer on a solid support via a single subunit with subsequent dissociation of non-covalently bound subunits in the presence of urea, and (2) entrapment of monomeric species into reversed micelles of Aerosol OT in octane. Isolated monomers were shown to be catalytically active, exhibiting KM values close to the parameters characteristic of the tetrameric forms. Like tetramers, isolated monomers did not use NADP7 as a coenzyme.
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Affiliation(s)
- P A Levashov
- Department of Chemistry, Moscow State University, Russia
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Abstract
Thermostability of alpha-chymotrypsin at normal pressure in reversed micelles depends on both an effective surfactant solvation degree and glycerol content in the system. The difference in alpha-chymotrypsin stability in reversed micelles at various glycerol concentrations [up to 60% (v/v)] was more pronounced at high surfactant degrees of solvation, R >/= 16. After a 1-h incubation at 40 degrees C in "aqueous" reversed micelles (in the absence of glycerol), alpha-chymotrypsin retained only 1% of initial catalytic activity and 10, 22, 59, and 48% residual activity in glycerol-solvated micelles with 20, 30, 50, and 60% (v/v) glycerol, respectively. The explanation of the observed effects is given in the frames of micellar matrix structural order increasing in the presence of glycerol as a water-miscible cosolvent that leads to the decreasing mobility of the alpha-chymotrypsin molecule and, thus the increase of its stability. It was found that glycerol or hydrostatic pressure could be used to stabilize alpha-chymotrypsin in reversed micelles; a lower pressure is necessary to reach a given level of enzyme stability in the presence of glycerol.
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Affiliation(s)
- R V Rariy
- Division of Chemical Enzymology, Department of Chemistry, Moscow State University, 119899 Moscow, Russia
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Klyachko NL, Vakula SV, Gladyshev VN, Tishkov VI, Levashov AV. Formate dehydrogenase in a reversed micelle system: regulation of catalytic activity and oligomeric composition of the enzyme. Biochemistry (Mosc) 1997; 62:1439-43. [PMID: 9481877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Formate dehydrogenases from the methylotrophic bacteria Pseudomonas sp. 101 and Mycobacterium vaccae N10 were studied in a system of Aerosol OT reversed micelles in octane. Three peaks of the catalytic activity were found on the plot of activity versus surfactant hydration degree (the size of the micellar inner cavity) which corresponded to functions of the enzyme in various oligomeric forms: monomeric, dimeric, and octameric. Kinetic data were confirmed by results of sedimentation analysis. The enzyme was chemically modified by a bifunctional reagent (dimethyl suberimidate) to obtain a catalytically active non-dissociating dimeric molecule of formate dehydrogenase. In the case of the covalently-linked non-dissociating dimeric enzyme, the peak which corresponded to the monomeric form of the enzyme was found to disappear from the catalytic activity curve.
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Affiliation(s)
- N L Klyachko
- Department of Chemical Enzymology, School of Chemistry, Lomonosov Moscow State University, Moscow, Russia
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Gazaryan IG, Klyachko NL, Dulkis YK, Ouporov IV, Levashov AV. Formation and properties of dimeric recombinant horseradish peroxidase in a system of reversed micelles. Biochem J 1997; 328 ( Pt 2):643-7. [PMID: 9371726 PMCID: PMC1218966 DOI: 10.1042/bj3280643] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Wild-type recombinant horseradish peroxidase purified and refolded from Escherichia coli inclusion bodies has been studied in the system of bis(2-ethylhexyl)sulphosuccinate sodium salt (Aerosol OT)-reversed micelles in octane. In contrast with native horseradish peroxidase the wild-type recombinant enzyme forms dimeric structures as judged by sedimentation analysis. Peroxidase substrates affect the equilibrium between monomeric and dimeric enzyme forms. The dependence of the catalytic activity of recombinant peroxidase on the degree of hydration of the surfactant exhibits two maxima with pyrogallol, o-phenylene- diamine, guaiacol and o-dianisidine, with different ratios of activities for the first and second maxima. The differences in activities of monomeric and dimeric forms of the recombinant horseradish peroxidase provide evidence for active-site screening in dimeric forms. This has been used to model a dimeric structure of recombinant horseradish peroxidase with the screened entrance to the active site. In the model structure obtained, three of eight glycosylation sites were screened. This might explain the absence of dimeric structures in native enzyme peroxidase. The system of reversed micelles provides, for the first time, evidence for the formation of dimeric structures by recombinant plant peroxidase with an altered substrate specificity compared with the native enzyme. Thus one can assume that haem-containing peroxidases in general are able to form dimeric structures.
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Affiliation(s)
- I G Gazaryan
- Department of Chemical Enzymology, Faculty of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119899 GSP, Russia
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Klyachko NL, Gazaryan IG, Ouporov IV, Levashov AV. Dimerization of recombinant horseradish peroxidase in a reversed micellar system. Biochemistry (Mosc) 1997; 62:1128-34. [PMID: 9461635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recombinant horseradish peroxidase reactivated from E. coli inclusion bodies was studied in a reversed micellar system of AOT in octane. The ability of the recombinant enzyme, in contrast to native horseradish peroxidase, to form a dimeric structure was found. The existence of the dimer was proved by results of sedimentation analysis. Dimer/monomer ratio in the enzyme-containing micelles and dimer catalytic activity were found to depend on the substrate used (pyrogallol, guaiacol, o-dianisidine, o-phenylenediamine). Computer modelling was used to describe possible structures of the dimeric recombinant horseradish peroxidase.
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Affiliation(s)
- N L Klyachko
- School of Chemistry, Lomonosov Moscow State University, Moscow, Russia
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Levashov AV, Ugolnikova AV, Ivanov MV, Klyachko NL. Formation of homo- and heterooligomeric supramolecular structures by D-glyceraldehyde-3-phosphate dehydrogenase and lactate dehydrogenase in reversed micelles of aerosol OT in octane. Biochem Mol Biol Int 1997; 42:527-34. [PMID: 9247710 DOI: 10.1080/15216549700202931] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The supramolecular structure of oligomeric enzymes can be specifically regulated by changing the size of an inner cavity of Aerosol OT reversed micelles in octane. Both D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and lactate dehydrogenase (LDH) reveal an ability to exist and function in monomeric, dimeric and tetrameric forms (homooligomers). Various heterooligomeric complexes, in particular, GAPDH monomer--LDH monomer, GAPDH dimer--LDH tetramer were detected in reversed micelles.
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Affiliation(s)
- A V Levashov
- Department of Chemistry, Moscow State University, Russia
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Klyachko NL, Sukhoruchenko TA, Levashov AV. Stability and stabilization of recombinant peroxidase in reversed micelles. Biochemistry (Mosc) 1997; 62:337-41. [PMID: 9275306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Stability of recombinant peroxidase lacking carbohydrate residues on the surface of the protein molecule has been characterized in reversed micelles of Aerosol OT in octane. The enzyme stability was found to depend on the surfactant hydration degree (w0 = [H2O]/[AOT]). Residual activity after 1 h incubation dropped to zero at w0 = 7 but was 54% at w0 = 25. However, the residual activity levels at all values of hydration degree were definitely low compared to that of glycosylated wild-type horseradish peroxidase. The stability of the enzyme apparently depends on the presence of carbohydrate residues. Stabilization of recombinant peroxidase in reversed micellar system involved sugar-containing co-surfactants such as Tweens and Spans is proposed. As an example, addition of 1 mM Span 80 (1% relative to AOT concentration) increased the recombinant peroxidase stability up to that of wild-type peroxidase.
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Affiliation(s)
- N L Klyachko
- Division of Chemical Enzymology, School of Chemistry, Lomonosov Moscow State University, Russia
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33
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Rariy RV, Bec N, Saldana JL, Nametkin SN, Mozhaev VV, Klyachko NL, Levashov AV, Balny C. High-pressure stabilization of alpha-chymotrypsin entrapped in reversed micelles of aerosol OT in octane against thermal inactivation. FEBS Lett 1995; 364:98-100. [PMID: 7538468 DOI: 10.1016/0014-5793(95)00344-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
alpha-Chymotrypsin (CT) solubilized in reversed micelles of sodium bis-(2-ethylhexyl)-sulfosuccinate (AOT) undergoes thermal inactivation and the enzyme stability decreases significantly when temperature increases (25-40 degrees C). The half-life of CT in micelles shows a bell-shaped dependence on the degree of hydration of AOT (wo) analogous to the previously obtained dependence on wo for the enzyme activity. The optima of catalytic activity and thermal stability have been observed under conditions where the diameter of the inner aqueous cavity of the micelle is close to the size of the enzyme molecule (wo = 10). Application of high hydrostatic pressure in the range of 1-1500 atm (bar) stabilizes CT against thermal inactivation at all hydration degrees (wo) from 7 to 20; the stabilization effect is most pronounced under the experimental conditions being far from the optimum for catalytic activity.
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Affiliation(s)
- R V Rariy
- Department of Chemistry, Moscow State University, Russian Federation
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Rariy RV, Klyachko NL, Borisova EA, Penagos CJ, Levashov AV. Lectin-like center in the molecule of alpha-chymotrypsin: formation of complexes with peroxidase and artificially glycosylated alpha-chymotrypsin. Biochem Mol Biol Int 1995; 36:31-7. [PMID: 7663420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Using the system of reversed micelles of Aerosol OT1 in octane as an instrument revealing the possibility of supramolecular structures formation, we have shown that the native alpha-chymotrypsin can form complexes with glycoproteins. Dimers of the native alpha-chymotrypsin with the artificially glycosylated one and with horseradish peroxidase (natural glycoprotein) were obtained. The position of the optimum on the dependence of the catalytic activity upon the hydration degree confirms the compact organization of the formed complexes. The ability of alpha-chymotrypsin to form such kind of complexes seems to play a key role in its absorption on glycocalix in vivo.
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Affiliation(s)
- R V Rariy
- Department of Chemistry, Moscow State University, Russian Federation
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Kabakov VE, Klyachko NL, Levashov AV. Revealing active site on the light subunit of penicillin acylase. Biochem Mol Biol Int 1995; 35:441-6. [PMID: 7663400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Serine-specific irreversible inhibitor phenylmethanesulfonyl fluoride (PMSF) inactivates penicillin acylase subunits, which were chromatographically separated under denaturing conditions and refolded by dialysis, in aqueous solution and Aerosol OT reversed micelles. The activities of both alpha and beta subunits decrease with increasing PMSF concentration but the dependence is no longer linear, in contrast with the native enzyme. The enzyme inactivated in aqueous solution, when solubilized in the micellar system at Wo = 12, exhibits an additional activity, which can be further inhibited by PMSF.
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Affiliation(s)
- V E Kabakov
- Department of Chemical Enzymology, Moscow State University, Russia
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Kabakov VE, Klyachko NL, Levashov AV. Catalytic activity of refolded penicillin acylase subunits in aqueous solution and aerosol ot reversed micelles in octane. Biochem Mol Biol Int 1994; 34:201-7. [PMID: 7531535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Refolded alpha and beta subunits of penicillin acylase were produced by gel-filtration under denaturing conditions followed by removal of urea through dialysis. Preparations of both renatured subunits hidrolysed specific substrate--phenylacetic acid p-nitroanilide in buffer and in the system of Aerosol OT reversed micelles, the alpha subunit being most catalytically active at Wo = 11.9, while the beta subunit--at Wo = 17.5. There was a good correlation between the position of the found maxima, the theoretically calculated optimal hydration degrees as well as the earlier reported profile of enzymatic activity for native enzyme in reversed micelles.
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Affiliation(s)
- V E Kabakov
- Department of Chemical Enzymology, Moscow State University, Russia
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37
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Levashov AV, Rariy RV, Martinek K, Klyachko NL. Artificially glycosylated alpha-chymotrypsin in reversed micelles of Aerosol OT in octane. A new approach to elucidation of the role of carbohydrate moieties in glycoproteins. FEBS Lett 1993; 336:385-8. [PMID: 8282098 DOI: 10.1016/0014-5793(93)80842-i] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A comparative study of native and artificially glycosylated alpha-chymotrypsin in reversed micelles of Aerosol OT in octane was carried out. D-Glucosamine and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide were used as modifying agents to yield glycosylated enzyme. Unlike the native alpha-chymotrypsin, the modified protein tended to form reversible oligomeric structures, revealed by the appearance of an additional maximum (characteristic of dimeric forms of protein functioning) as a result of the enzyme catalytic activity being dependent on the AOT hydration degree. Dependence of the enzyme catalytic activity on the surfactant concentration in the case of the modified enzyme was similar to that of glycoproteins, and suggests its membrane affinity. The role of carbohydrate moieties in the functioning of glycoproteins is discussed.
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Affiliation(s)
- A V Levashov
- Department of Chemistry, Moscow State University, Russian Federation
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Kabakov VE, Merker S, Klyachko NL, Martinek K, Levashov AV. Regulation of the supramolecular structure and the catalytic activity of penicillin acylase from Escherichia coli in the system of reversed micelles of Aerosol OT in octane. FEBS Lett 1992; 311:209-12. [PMID: 1383038 DOI: 10.1016/0014-5793(92)81104-t] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The properties of penicillin acylase from E. coli solubilized by hydrated reversed micelles (RM) of Aerosol OT in octane were studied. The dependence of catalytic activity on the hydration degree, a parameter which determines the size of the micelle inner cavity, has a curve with three optima, each one corresponding to the enzyme functioning either in a dimer form (wo = 23) or in a form of separate subunits, a heavy one, beta, and a light one, alpha (wo = 20 and 14, respectively). The reversible dissociation of the enzyme was confirmed by ultracentrifugation followed by electrophoresis.
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Affiliation(s)
- V E Kabakov
- Department of Chemical Enzymology, Moscow State University, Russia
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Kabanov AV, Nametkin SN, Chernov NN, Klyachko NL, Levashov AV. Subunit separation in reversed micelle system reveals the existence of active centers both on light and heavy gamma-glutamyltransferase subunits. FEBS Lett 1991; 295:73-6. [PMID: 1684940 DOI: 10.1016/0014-5793(91)81388-o] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Regulation of supra-macromolecular composition and catalytic activity of a heterodimeric enzyme, gamma-glutamyltransferase, in the system of Aerosol OT (sodium bis(2-ethylhexyl) sulfosuccinate) reversed micelles in octane were studied. Variation of the surfactant hydration degree (parameter, determining dimensions of the polar inner cavity of the micelle) causes a reversible dissociation of the enzyme to light and heavy subunits. Both enzyme subunits possess catalytic activity. The light and heavy subunits of the enzyme were separated on a preparative scale in a reversed micelle system using ultracentrifugation. The active centers of gamma-glutamyltransferase were studied using its irreversible inhibitor--AT-125 (L-(alpha S, 5S)-alpha-amino-3-chloro-4,5-dihydro-5-isoxazoleacetic acid). Separation of the gamma-glutamyltransferase subunits results in the 'opening' of a new active center located at the heavy subunit. In the dimer form of the enzyme this center is masked and it is not accessible to both substrate and inhibitor molecules.
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Affiliation(s)
- A V Kabanov
- Department of Chemistry, Moscow State University, Russia
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Kabanov AV, Klyachko NL, Nametkin SN, Merker S, Zaroza AV, Bunik VI, Ivanov MV, Levashov AV. Engineering of functional supramacromolecular complexes of proteins (enzymes) using reversed micelles as matrix microreactors. Protein Eng 1991; 4:1009-17. [PMID: 1726270 DOI: 10.1093/protein/4.8.1009] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The size of the inner water cavity of reversed micelles formed in a triple system 'water-surfactant-organic solvent' can be widely varied by changing the degree of surfactant hydration. This gives grounds to use reversed micelles as matrix microreactors for the design of supramolecular complexes of proteins. Using ultracentrifugation analysis, it has been demonstrated that the oligomeric composition of various enzymes (ketoglutarate dehydrogenase, alkaline phosphatase, lactic dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase) solubilized in reversed micelles of Aerosol OT [sodium bis(2-ethylehexyl)sulfosuccinate] in octane changes upon variation of the degree of hydration. An oligomeric complex forms under conditions when the radius of the micelle inner cavity is big enough to incorporate this complex as a whole. At lower degrees of hydration the micelles 'uncouple' such complexes to their components. The catalytic properties of various oligomeric complexes have been studied. Possibilities of using reversed micelles for the separation of subunits of oligomeric enzymes under non-denaturating conditions have been demonstrated. In particular, the isolated subunits of alkaline phosphatase, lactic dehydrogenase and glyceraldehyde-3-phosphate have been found to be active in Aerosol OT reversed micelles. The dependences of the catalytic activity of oligomeric enzymes represent saw-like curves. The maxima of the catalytic activity observed at these curves relate to the functioning of various oligomeric forms of an enzyme. The radii of the micelle inner cavity under conditions when these maxima are observed correlate with the linear dimensions of the enzyme oligomeric forms. Correlation of the position of a maximum with the shape of an oligomeric complex is discussed.
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Affiliation(s)
- A V Kabanov
- Department of Chemical Enzymology, Faculty of Chemistry, M.V. Lomonosov Moscow State University, USSR
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Kabanov AA, Nametkin SN, Klyachko NL, Levashov AV. Regulation of the catalytic activity and oligomeric composition of enzymes in reversed micelles of surfactants in organic solvents. FEBS Lett 1991; 278:143-6. [PMID: 1991503 DOI: 10.1016/0014-5793(91)80103-a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The phenomenon of regulation of the catalytic activity of enzymes via changing their oligomeric composition in the system of reversed micelles of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) in octane was studied using alpha-chymotrypsin (CT) from bovine brain and alkaline phosphatase (AP) from calf intestinal mucosa. The dependences of the enzyme catalytic activity on the AOT hydration degree (Wo = [H2O]/[AOT]), the parameter determining the radius (rc) of the inner cavity of micelles, usually represent the bell-shaped curves. The maximal catalytic activity is observed at such Wo when rc is equal to the size of the enzyme molecule. The position of this maximum strictly correlates with the enzyme oligomeric composition. Thus, in the case of CT this is observed at Wo = 12 when rc is equal to the radius (rp) of the CT globule. In the case of artificially produced conjugate containing six cross-linked CT molecules, this is observed at Wo = 43 when rc is equal to the radius of the sphere surrounding the absolute octahedron composed of six CT globules. The dependence of the catalytic activity of AP on Wo represents a curve with two maxima that are observed when rc is equal to rp of either AP monomer (Wo = 17) or AP dimer (Wo = 25). Ultracentrifugation experiments revealed that variation of Wo causes a change in the oligomeric composition of AP - its transition from monomeric (Wo less than 20) to dimeric form (Wo greater than 20). Hence, the observed maxima correspond to functioning of different oligomeric forms of AP.
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Affiliation(s)
- A A Kabanov
- Department of Chemical Enzymology, Moscow State University, USSR
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Abstract
Using reversed micelles of surfactants solvated by water-organic cosolvent mixtures as a matrix for enzyme entrapping, it is possible to fix the highly reactive alpha-chymotrypsin form. The reactivity of alpha-chymotrypsin towards nonspecific substrates increases to the extent comparable with that observed in reactions involving specific substrates.
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Affiliation(s)
- A V Levashov
- Department of Chemistry, M.V. Lomonosov Moscow State University, USSR
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Mozhaev VV, Khmelnitsky YL, Sergeeva MV, Belova AB, Klyachko NL, Levashov AV, Martinek K. Catalytic activity and denaturation of enzymes in water/organic cosolvent mixtures. Alpha-chymotrypsin and laccase in mixed water/alcohol, water/glycol and water/formamide solvents. Eur J Biochem 1989; 184:597-602. [PMID: 2806243 DOI: 10.1111/j.1432-1033.1989.tb15055.x] [Citation(s) in RCA: 169] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The dependence of the catalytic activities of alpha-chymotrypsin and laccase on the concentration of organic cosolvents (alcohols, glycols and formamides) in mixed aqueous media has a pronounced threshold character: it does not change up to a critical concentration of the non-aqueous cosolvents added, yet further increase of the latter (by only a small percentage, by vol.) leads to an abrupt decrease in enzyme activity. Fluorescence studies indicate that the inactivation results from reversible conformational changes (denaturation) of the enzymes. There is a linear correlation between the critical concentration of residual water (at which the enzyme inactivation occurs in a threshold manner) and the hydrophobicity of the organic cosolvents added. A quantitative criterion is suggested for the selection of organic cosolvents to be used for enzymatic reactions in homogeneous water/organic solvent media.
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Affiliation(s)
- V V Mozhaev
- Chemistry Department, Moscow State University, USSR
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Kabanov AV, Khrutskaya MM, Eremin SA, Klyachko NL, Levashov AV. A new way in homogeneous immunoassay: reversed micellar systems as a medium for analysis. Anal Biochem 1989; 181:145-8. [PMID: 2479291 DOI: 10.1016/0003-2697(89)90408-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Possibilities of a new principle for the homogeneous enzyme immunoassay utilizing the systems of surfactant reversed micelles in organic solvents have been demonstrated taking thyroxine determination as an example. The catalytic activity of an enzyme, solubilized in such systems, is determined by the ratio of geometric dimensions of the micellar matrice and the enzyme molecule. The addition of antibodies against thyroxine to the peroxidase-thyroxine conjugate, solubilized in the system of reversed micelles of aerosol OT in octane, leads to the formation of the immune complex whose size differs substantially from that of the initial enzyme-antigen conjugate. This induces changes in the peroxidase catalytic activity. The addition of free thyroxine to the system stimulates the conjugate release from the immune complex and, consequently, the reduction of the peroxidase activity to the initial level. Sensitivity of the analysis in reversed micellar systems can be regulated by changing the surfactant hydration degree. Substances of different nature (both hydrophobic and hydrophylic) can be solubilized in reverse micellar systems under standard conditions, which allows determination of water insoluble antigens.
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Affiliation(s)
- A V Kabanov
- Division for Chemical Enzymology, M. V. Lomonosov Moscow State University, USSR
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Kabanov AV, Nametkin SN, Evtushenko GN, Chernov NN, Klyachko NL, Levashov AV, Martinek K. A new strategy for the study of oligomeric enzymes: gamma-glutamyltransferase in reversed micelles of surfactants in organic solvents. Biochim Biophys Acta 1989; 996:147-52. [PMID: 2473781 DOI: 10.1016/0167-4838(89)90240-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A heterodimeric enzyme (gamma-glutamyltransferase) was studied in the reversed micellar medium of Aerosol OT (AOT) in octane. As was shown earlier, the size (radius) of inner cavity of the AOT-reversed micelles is determined by their hydration degree, i.e., [H2O]/[AOT] molar ratio, in the system. Owing to this, the dependence of hydrolytic, transpeptidation and autotranspeptidation activities of the enzyme on the hydration degree was investigated using L- and D-isomers of gamma-glutamyl(3-carboxy-4-nitro)anilide and glycylglycine as substrates. For all of the reaction types, the observed dependences are curves with three optima. The optima are found at the hydration degrees, [H2O]/[AOT] = 11, 17 and 26 when the inner cavity radii of reversed micelles are equal to the size of light (Mr 21,000) and heavy (Mr 54,000) subunits of gamma-glutamyltransferase, and to their dimer (Mr 75,000), respectively. Ultracentrifugation experiments showed that a change of the hydration degree resulted in a reversible dissociation of the enzyme to light and heavy subunits. The separation of light and heavy subunits of gamma-glutamyltransferase formed in reversed micelles was carried out and their catalytic properties were studied. The two subunits catalyze hydrolysis and transpeptidation reactions; autotranspeptidation reaction is detected only in the case of the heavy subunit. These findings imply that the reversed micelles of surfactants in organic solvents function as the matrices with adjustable size permitting to regulate the supramolecular structure and the catalytic activity of oligomeric enzymes.
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Affiliation(s)
- A V Kabanov
- Department of Chemistry, Moscow State University, U.S.S.R
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Martinek K, Klyachko NL, Kabanov AV, Khmelnitsky YuL, Levashov AV. The second E.C. Slater lecture. Micellar enzymology: its relation to membranology. Biochim Biophys Acta 1989; 981:161-72. [PMID: 2659086 DOI: 10.1016/0005-2736(89)90024-2] [Citation(s) in RCA: 241] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Micellar enzymology, a new trend in molecular biology, studies catalysis by enzymes entrapped in hydrated reversed micelles composed of surfactants (phospholipids, detergents) in organic solvents. The key research problems of micellar enzymology and its relation to enzyme membranology are discussed.
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Affiliation(s)
- K Martinek
- Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, Prague
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Klyachko NL, Levashov AV, Gavrilova EM, Egorov AM, Martinek K, Berezin IV. Bioluminescent analysis in a biomembrane-like medium consisting of surfactant, hydrocarbon solvent, and water: ATP determination using firefly luciferase. Ann N Y Acad Sci 1987; 501:267-70. [PMID: 3475018 DOI: 10.1111/j.1749-6632.1987.tb45720.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Klyachko NL, Levashov AV, Pshezhetsky AV, Bogdanova NG, Berezin IV, Martinek K. Catalysis by enzymes entrapped into hydrated surfactant aggregates having lamellar or cylindrical (hexagonal) or ball-shaped (cubic) structure in organic solvents. Eur J Biochem 1986; 161:149-54. [PMID: 3780732 DOI: 10.1111/j.1432-1033.1986.tb10135.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Instead of aqueous solutions, universally recognized in enzymology, ternary systems of the water/organic solvent/surfactant type are suggested as liquid-crystalline media for enzymatic reactions. Two systems, water/octane/Aerosol OT and water/cyclohexane/Brij 96, have been used to solubilize acid and alkaline phosphatases and peroxidase. The enzymes under study do function in liquid-crystalline mesophases having lamellar, cylindrical (reversed hexagonal) and ball-shaped (reversed cubic) packing of the surfactant molecules. A significant result is that the phase transition from one liquid-crystalline structure to another entails, as a rule, a reversible change in the catalytic activity of the solubilized enzyme.
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Lerbs S, Lerbs W, Klyachko NL, Romanko EG, Kulaeva ON, Wollgiehn R, Parthier B. Gene expression in cytokinin-and light-mediated plastogenesis of Cucurbita cotyledons: ribulose-1,5-bisphosphate carboxylase/oxygenase. Planta 1984; 162:289-298. [PMID: 24253161 DOI: 10.1007/bf00396739] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/1983] [Accepted: 03/13/1984] [Indexed: 06/02/2023]
Abstract
The effects of a cytokinin (N(6)-benzyladenine, BA) and light on plastogenesis have been studied in detached Cucurbita cotyledons using the key enzyme of photosynthetic CO2 fixation, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCase), as an example of a coordinated program of plastid and nucleo-cytoplasmic gene expression. Treatment of etiolated cotyledons with either BA in darkness or in light or light alone results in a marked and correlated stimulation of enzyme activity, quantity and biosynthesis (in-vivo [(14)C]leucine incorporation into immunoprecipitated enzyme protein), indicating an increase of de-novo synthesis under the influence of the two effectors. Cell-free translation of non-polyadenylated (poly(A)(-))RNA in an Escherichia coli system and total RNA in a wheat-germ system likewise demonstrate a light and hormone-dependent increase in the amounts of translatable mRNAs for the large (LS) and small subunits (SS) of RuBPCase (among other polypeptides). Hybridisation of poly(A)(-)RNA with a nick-translated LS gene of spinach RuBPCase reveals also two-to three-fold BA-or light-induced enhancement of LS mRNA content. Indications for stimulation of SS mRNA transcription are derived from inhibitor experiments with cordycepin. We conclude that the observed stimulation of de-novo RuBPCase synthesis by cytokinin and by light can be referred to the level of mRNA transcription, but it remains open whether this is a primary action. Furthermore, our results indicate that the coaction of the two exogenous factors is additive at different steps of RuBPCase formation, indicating independent actions in the causal chain between effector-signal transduction and RuBPCase gene expression.
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Affiliation(s)
- S Lerbs
- Institut für Biochemie der Pflanzen, Akademie der Wissenschaften der DDR, Weinberg, DDR-4010, Halle/Saale
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Martinek K, Levashov AV, Khmelnitsky YL, Klyachko NL, Berezin IV. Colloidal solution of water in organic solvents: a microheterogeneous medium for enzymatic reactions. Science 1982; 218:889-91. [PMID: 6753152 DOI: 10.1126/science.6753152] [Citation(s) in RCA: 174] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
To simulate in vitro the conditions under which enzymes act in vivo, enzyme molecules have been entrapped in hydrated reverse micelles of a surfactant in organic solvents. In this system the catalytic activity of one of the enzymes studied (peroxidase) became much higher than in water, and the specificity of the other enzyme (alcohol dehydrogenase) was dramatically altered.
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