Dissociation of lactate dehydrogenase in aqueous and reversed micellar solutions. A time-resolved polarized fluorescence study
| العنوان: | Dissociation of lactate dehydrogenase in aqueous and reversed micellar solutions. A time-resolved polarized fluorescence study |
|---|---|
| المؤلفون: | Cees Veeger, Yuri L. Khmelnitsky, Antonie J. W. G. Visser, A. van Hoek |
| المصدر: | European Journal of Biochemistry, 212, 63-67 European Journal of Biochemistry 212 (1993) |
| سنة النشر: | 1993 |
| مصطلحات موضوعية: | Aqueous solution, L-Lactate Dehydrogenase, Swine, Chemistry, Fluorescence spectrometry, Biophysics, Biochemie, Fluorescence Polarization, Photochemistry, Oligomer, Micelle, Biochemistry, Dissociation (chemistry), chemistry.chemical_compound, Biofysica, Solubility, Pulmonary surfactant, Lactate dehydrogenase, Micellar solutions, Life Science, Animals, Organic chemistry, Micelles |
| الوصف: | Dissociation behavior of lactate dehydrogenase from hog muscle, both in aqueous solution and reversed micelles of sodium bis(2-ethylhexyl sulfosuccinate) in octane was studied using timeresolved polarized fluorescence spectroscopy. It was found that, in aqueous solutions, t6e enzyme underwent partial dissociation with the formation of isolated subunits at enzyme concentrations below 8 nM. Dissociation of the enzyme also took place upon entrapment of lactate dehydrogenase into reversed micelles under conditions of low surfactant hydration, when micelles were not large enough to accomodate a whole protein molecule. Dissociation behavior of oligomeric enzymes in general and lactate dehydrogenase (LDH) in particular has received much attention because of the close interrelation existing between functional properties and the association state of these complex proteins [l]. Analysis of available experimental data shows that, despite considerable progress in this field, certain aspects of the dissociation phenomenon still have to be elucidated. For example, although it is generally recognized that the dilution of aqueous LDH solutions leads to the dissociation of the enzyme, different reports give quite contradictory estimates of the actual lower concentration limit of existence of the tetrameric form, ranging from 0.7 nM [2] to 1 pM [3] and 7 pM [4]. One of possible reasons for these discrepancies is that the investigations mentioned above were performed using ultracentrifugation or gel-permeation chromatography. An inherent feature of these experimental techniques is that they inevitably generate a gradient of the protein concentration, which, in turn, could affect the concentration-dependent association state of the enzyme. Another interesting aspect of the dissociation behavior of oligomeric enzymes has been recently revealed within the framework of micellar enzymology, which deals with enzymes entrapped in surfactant reversed micelles in organic solvents [5, 61. Several oligomeric enzymes, including LDH, have been reported to dissociate into monomers or dimers during the entrapment into reversed micelles [7, 81. The existence of reversed micelles containing monomers and dimers of oligomeric enzymes was derived from measurements of catalytic activity and ultracentrifugation studies, performed at varying surfactant hydrations [7, 81, and has not |
| وصف الملف: | application/octet-stream; text/html |
| اللغة: | English |
| تدمد: | 0014-2956 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cab5ca7dd55c98f72811f0d7ab097797Test https://doi.org/10.1111/j.1432-1033.1993.tb17633.xTest |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....cab5ca7dd55c98f72811f0d7ab097797 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 00142956 |
|---|