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Abstract
1. Loading the isolated perfused liver from well-fed rats with xylitol (20mm) caused a depletion of adenine nucleotides and P(i) and an accumulation of alpha-glycerophosphate. The ATP content fell to 66% of the control value after 10min and to 32% after 80min. The ADP and AMP contents also fell. After 80min 63% of the total adenine nucleotides and 59% of the P(i) had been lost. 2. The alpha-glycerophosphate content rose from 0.13 to 4.74mumol/g at 10min and reached 8.02mumol/g at 40min. 3. Xylitol was rapidly metabolized, the main products being glucose, lactate and pyruvate. 4. The [lactate]/[pyruvate] ratio in the presence of xylitol rose to 30-40. 5. On perfusion of livers from starved animals the main product of xylitol metabolism was glucose and the mean ratio xylitol removed/glucose formed was 1.29 (corrected for endogenous glucose and lactate production). This is close to the predicted value of 1.2. 6. Evidence is presented indicating that the loss of adenine nucleotides caused by xylitol is not due to the increased ATP consumption but to the accumulation of alpha-glycerophosphate and depletion of P(i). 7. The loss of adenine nucleotides accounts for the hyperuricaemia which can occur after xylitol infusion in man. 8. The relevance of the findings to the clinical use of xylitol as an energy source is discussed.
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Affiliation(s)
- H F Woods
- Metabolic Research Laboratory, Nuffield Department of Clinical Medicine, and Department of the Regius Professor of Medicine, Radcliffe Infirmary, Oxford OX2 6HE, U.K
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2
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Off-line FIA monitoring of d-sorbitol consumption during l-sorbose production using a sorbitol biosensor. Anal Chim Acta 2009; 644:68-71. [DOI: 10.1016/j.aca.2009.04.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 03/19/2009] [Accepted: 04/08/2009] [Indexed: 11/20/2022]
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3
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Jeffery J, Jörnvall H. Sorbitol dehydrogenase. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 61:47-106. [PMID: 3281420 DOI: 10.1002/9780470123072.ch2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- J Jeffery
- Department of Biochemistry, University of Aberdeen, Scotland, UK
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4
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Hwang YC, Bakr S, Ellery CA, Oates PJ, Ramasamy R. Sorbitol dehydrogenase: a novel target for adjunctive protection of ischemic myocardium. FASEB J 2003; 17:2331-3. [PMID: 14525943 DOI: 10.1096/fj.03-0128fje] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Sorbitol dehydrogenase (SDH) is a polyol pathway enzyme that catalyzes conversion of sorbitol to fructose. Recent studies have demonstrated that activation of aldose reductase, the first enzyme of the polyol pathway, is a key response to ischemia and that inhibition of aldose reductase reduces myocardial ischemic injury. In our efforts to understand the role of pathway in affecting metabolism under normoxic and ischemic conditions, as well as in ischemic injury in myocardium, we investigated the importance of SDH by use of a specific inhibitor (SDI), CP-470,711. SDH inhibition increased glucose oxidation, whereas palmitate oxidation remained unaffected. Global ischemia increased myocardial SDH activity by approximately 1.5 fold. The tissue lactate/pyruvate ratio, a measure of cytosolic NADH/NAD+, was reduced by SDH inhibition under both normoxic and ischemic conditions. ATP was higher in SDI hearts during ischemia and reperfusion. Creatine kinase release during reperfusion, a marker of myocardial ischemic injury, was markedly attenuated in SDH-inhibited hearts. These data indicate that myocardial SDH activation is a component of ischemic response and that interventions that inhibit SDH protect ischemic myocardium. Furthermore, these data identify SDH as a novel target for adjunctive cardioprotective interventions.
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Affiliation(s)
- Yuying C Hwang
- Division of Surgical Science, Department of Surgery, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA
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5
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Abstract
This chapter critically examines the concept of the polyol pathway and how it relates to the pathogenesis of diabetic peripheral neuropathy. The two enzymes of the polyol pathway, aldose reductase and sorbitol dehydrogenase, are reviewed. The structure, biochemistry, physiological role, tissue distribution, and localization in peripheral nerve of each enzyme are summarized, along with current informaiton about the location and structure of their genes, their alleles, and the possible links of each enzyme and its alleles to diabetic neuropathy. Inhibitors of pathway enzyme and results obtained to date with pathway inhibitors in experimental models and human neuropathy trials are updated and discussed. Experimental and clinical data are analyzed in the context of a newly developed metabolic odel of the in vivo relationship between nerve sorbitol concentration and metabolic flux through aldose reuctase. Overall, the data will be interpreted as supporting the hypothesis that metabolic flux through the polyol pathway, rather than nerve concentration of sorbitol, is the predominant polyol pathway-linked pathogeneic factor in diabetic preipheral nerve. Finally, key questions and future directions for bsic and clinical research in this area are considered. It is concluded that robust inhibition of metabolic flux through the polyol pathway in peripheral nerve will likely result in substantial clinical benefit in treating and preventing the currently intractable condition of diabetic peripheral neuropathy. To accomplish this, it is imperative to develop and test a new generation of "super-potent" polyol pathway inhibitors.
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Affiliation(s)
- Peter J Oates
- Department of Cardiovascular and Metabolic Diseases, Pfizer Global Research and Development, Groton, Connecticut 06340, USA
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6
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Purification and Properties of NAD(+)-dependent Sorbitol Dehydrogenase from Bacillus fructosus. Biosci Biotechnol Biochem 1999; 63:573-4. [PMID: 27393263 DOI: 10.1271/bbb.63.573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Sorbitol dehydrogenase (EC 1.1.1.14), which catalyzes the NAD(+)-linked interconversion of D-sorbitol and D-fructose, was purified and crystallized from cell-free extracts of Bacillus fructosus grown on D-sorbitol as a sole carbon source. The crystalline enzyme was homogeneous on disc electrophoresis and ultracentrifugation. The molecular weight was 102,000 by the sedimentation equilibrium method. The enzyme acted specifically on D-sorbitol, and showed an optimum pH at 9.0. The K m values for D-sorbitol and NAD(+) were 1.1×10(-2) M and 2.2×10(-4) M, respectively. The enzyme activity was inhibited by p-chloromercuribenzoate, Ag(+), Hg(2+), and Cu(2+).
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7
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Shinohara R, Mano T, Nagasaka A, Sawai Y, Uchimura K, Hayashi R, Hayakawa N, Nagata M, Makino M, Kakizawa H, Itoh Y, Nakai A, Itoh M. Effects of thyroid hormone on the sorbitol pathway in streptozotocin-induced diabetic rats. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1425:577-86. [PMID: 9838221 DOI: 10.1016/s0304-4165(98)00111-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sorbitol accumulation plays an important role in diabetic complications involving the kidney, nerves, retina, lens and cardiac muscle. To investigate the influence of thyroid hormone on the sorbitol pathway, we studied the effects of thyroid hormone on polyol metabolism in normal and diabetic rats. Rats were divided into three groups: controls, streptozotocin (STZ)-induced diabetic euthyroid rats (DM) and STZ-induced diabetic hyperthyroid (thyroxine-injected) rats (DM+HT). The sorbitol (Sor) concentrations in the kidney, liver and sciatic nerve (2.53+/-0.74, 0.97+/-0.16 and 24.0+/-5.1 nmol/mg protein, respectively) of the DM rats were significantly higher than those (1.48+/-0.31, 0.58+/-0.13 and 3. 1+/-0.6 nmol/mg protein) of the control rats. The Sor concentrations in the kidney and sciatic nerve of the DM+HT rats (1.26+/-0.29 and 9. 40+/-1.2 nmol/mg protein) were significantly lower than those in the DM rats. These values were reduced in the liver, unchanged in the kidney, and increased in the sciatic nerve from the hyperthyroid rats without diabetes. Thyroid hormone reduced the aldose reductase (AR) activities in the kidney, liver and sciatic nerve of the DM rats, and similarly reduced AR in the kidney and liver, but not in the sciatic nerve, of the non-diabetic rats. The sorbitol dehydrogenase (SDH) activities were decreased by thyroid hormone in the kidney and liver but not the sciatic nerve of DM rats. In the non-diabetic rats, this enzyme activity was decreased in liver, but not in kidney or sciatic nerve. A positive correlation between the Sor concentration and AR activity was observed in the kidney and liver but not in the sciatic nerve from control, DM and DM+HT rats. A negative correlation was observed between the Sor concentration and SDH activities in the same organs. These data suggest that thyroid hormone affects the sorbitol pathway, but the detailed mechanism whereby this hormone reduces the sorbitol content (especially in diabetic rats) remains to be clarified.
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Affiliation(s)
- R Shinohara
- Department of Biochemistry, Fujita Health University School of Hygiene, Toyoake, Aichi 470-1192, Japan
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8
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9
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Hendrix DL, Salvucci ME. Polyol metabolism in homopterans at high temperatures: accumulation of mannitol in aphids (Aphididae: Homoptera) and sorbitol in whiteflies (Aleyrodidae: Homoptera). Comp Biochem Physiol A Mol Integr Physiol 1998. [DOI: 10.1016/s1095-6433(98)10058-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Lindstad RI, Köll P, McKinley-McKee JS. Substrate specificity of sheep liver sorbitol dehydrogenase. Biochem J 1998; 330 ( Pt 1):479-87. [PMID: 9461546 PMCID: PMC1219163 DOI: 10.1042/bj3300479] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The substrate specificity of sheep liver sorbitol dehydrogenase has been studied by steady-state kinetics over the range pH 7-10. Sorbitol dehydrogenase stereo-selectively catalyses the reversible NAD-linked oxidation of various polyols and other secondary alcohols into their corresponding ketones. The kinetic constants are given for various novel polyol substrates, including L-glucitol, L-mannitol, L-altritol, D-altritol, D-iditol and eight heptitols, as well as for many aliphatic and aromatic alcohols. The maximum velocities (kcat) and the substrate specificity-constants (kcat/Km) are positively correlated with increasing pH. The enzyme-catalysed reactions occur by a compulsory ordered kinetic mechanism with the coenzyme as the first, or leading, substrate. With many substrates, the rate-limiting step for the overall reaction is the enzyme-NADH product dissociation. However, with several substrates there is a transition to a mechanism with partial rate-limitation at the ternary complex level, especially at low pH. The kinetic data enable the elucidation of new empirical rules for the substrate specificity of sorbitol dehydrogenase. The specificity-constants for polyol oxidation vary as a function of substrate configuration with D-xylo> D-ribo > L-xylo > D-lyxo approximately L-arabino > D-arabino > L-lyxo. Catalytic activity with a polyol or an aromatic substrate and various 1-deoxy derivatives thereof varies with -CH2OH > -CH2NH2 > -CH2OCH3 approximately -CH3. The presence of a hydroxyl group at each of the remaining chiral centres of a polyol, apart from the reactive C2, is also nonessential for productive ternary complex formation and catalysis. A predominantly nonpolar enzymic epitope appears to constitute an important structural determinant for the substrate specificity of sorbitol dehydrogenase. The existence of two distinct substrate binding regions in the enzyme active site, along with that of the catalytic zinc, is suggested to account for the lack of stereospecificity at C2 in some polyols.
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Affiliation(s)
- R I Lindstad
- Institute of Biochemistry, University of Oslo, Oslo, Norway
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11
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Marini I, Bucchioni L, Borella P, Del Corso A, Mura U. Sorbitol dehydrogenase from bovine lens: purification and properties. Arch Biochem Biophys 1997; 340:383-91. [PMID: 9143345 DOI: 10.1006/abbi.1997.9882] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Bovine lens sorbitol dehydrogenase (L-iditol:NAD+ 2-oxidoreductase, EC 1.1.1.14) (SDH) was purified to electrophoretic homogeneity (51 U/mg of protein) and characterized for both kinetic and some structural properties. The enzyme proves to be a homotetramer of 156 kDa containing one equivalent of zinc ion per subunit. Metal chelators such as EDTA and 1,10-phenanthroline determine a loss of enzyme activity which can be specifically recovered by addition of either zinc or manganese ions. Inactivation induced not only by metal chelators but also by thiol reagents is effectively prevented by the pyridine cofactor. Bovine lens SDH is active on polyalcohols and keto-sugars with more than three carbon atoms, and also requires special steric constraints for substrate recognition. Of the polyols, xylitol is the most effective substrate (kcat/KM of 8.1 s-1 mM-1), followed by sorbitol (kcat/KM of 1.59 s-1 mM-1); fructose, the most effective carbonyl substrate, displays a kcat/KM of only 0.9 s-1 mM-1. Analysis at the steady state of initial velocities as a function of the concentration of different substrates and cofactors and studies of product inhibition indicate for both fructose reduction and sorbitol oxidation a Theorell and Chance-type kinetic mechanism of action.
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Affiliation(s)
- I Marini
- Dipartimento di Fisiologia e Biochimica, Università di Pisa, Italy
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12
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Properties of sorbitol dehydrogenase from Pseudomonas sp. KS-E1806 and comparison with other sorbitol dehydrogenases. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0922-338x(97)82064-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Maret W. Human sorbitol dehydrogenase--a secondary alcohol dehydrogenase with distinct pathophysiological roles. pH-dependent kinetic studies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1997; 414:383-93. [PMID: 9059643 DOI: 10.1007/978-1-4615-5871-2_44] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- W Maret
- Center for Biochemical and Biophysical Sciences and Medicine, Harvard Medical School, Boston, Massachusetts 02115, USA
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14
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Lindstad RI, McKinley-McKee JS. Reversible inhibition of sheep liver sorbitol dehydrogenase by thiol compounds. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 241:142-8. [PMID: 8898899 DOI: 10.1111/j.1432-1033.1996.0142t.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Reversible inhibition of sheep liver sorbitol dehydrogenase by various thiol compounds has been studied. Most species inhibit the enzyme-catalyzed reaction competitively with respect to sorbitol, due to the formation of ternary enzyme-NAD-thiol complexes. The primary interaction of thiol inhibitors with the enzyme active site involves the catalytic zinc atom, and a bidentate mode of binding to the active site metal is indicated for some bifunctional thiols in their ternary complexes. Enzyme-bound thiolate facilitates NAD binding to the enzyme and vice versa, mainly due to mutual electrostatic stabilization. The aromatic thiols 1-thio-1-phenylmethane and 1-thio-2-phenylethane are especially potent inhibitors with an inhibition constant of 0.30 microM at pH 9.9. The inhibitory effect of aliphatic thiols, which is positively correlated with alkyl chain length, parallels that observed previously with the related enzyme horse liver alcohol dehydrogenase and indicates that interaction with an enzymic hydrophobic site is important for inhibitor binding. Several reversible inhibitors afford competitive protection against affinity labelling of the enzyme by 2-bromo-3-(5-imidazolyl) propionic acid due to the formation of binary enzyme-thiol complexes. The present study establishes thionucleosides as a novel class of potent sorbitol dehydrogenase inhibitors. The thionucleosides 6-thioguanosine and 6-thioinosine gave mixed inhibition with respect to sorbitol, due to the formation of enzyme-NAD-inhibitor and enzyme-NADH-inhibitor complexes. In order to enable a correlation of the substrate and inhibitor specificities of the enzyme, the kinetic constants for several sorbitol dehydrogenase substrates were determined. L-threitol and DL-1-phenyl-1,2-ethanediol are good substrates with, at high pH, kinetic constants similar to those of sorbitol. The potent inhibition by dithiothreitol and the aromatic thiols thus parallels the substrate specificity of the enzyme. The sorbitol competitive inhibitor 1-thiosorbitol is also a substrate with, at pH 7.4, a maximum velocity of 0.17 s-1 and a Michaelis constant of 8.6 mM. Dithiothreitol forms a tight ternary complex with the enzyme-NAD complex with a molar absorbance of 16.4 x 10(3) M-1 . cm-1 at 311 nm. A spectrophotometric titration of the enzyme with NAD in the presence of dithiothreitol is described, which enables an accurate determination of the concentration of sorbitol dehydrogenase active sites and confirms the activity assay of the enzyme.
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Affiliation(s)
- R I Lindstad
- Institute of Biochemistry, University of Oslo, Norway
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15
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Lindstad RI, Hermansen LF, McKinley-McKee JS. Inhibition and activation studies on sheep liver sorbitol dehydrogenase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 221:847-54. [PMID: 8174565 DOI: 10.1111/j.1432-1033.1994.tb18799.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Reversible inhibition and activation, as well as protection against affinity labelling with DL-2-bromo-3-(5-imidazolyl)propionic acid, of sheep liver sorbitol dehydrogenase have been studied. The results presented are discussed in terms of enzyme active-site properties and may have potential applications for drug design. Kinetics with mainly sorbitol competitive inhibitors reveals that aliphatic thiols are generally the most potent inhibitors of enzyme activity. Inhibition and inactivation by heterocyclics parallel that seen previously with sorbitol dehydrogenase from other sources as well as with alcohol dehydrogenase from yeast. However, there are significant differences in relation to the structurally similar horse liver alcohol dehydrogenase, as the catalytic zinc of sorbitol dehydrogenase is more easily removed by chelating molecules. Several aldose reductase inhibitors are shown to also inhibit sorbitol dehydrogenase, but at concentrations unlikely to be reached clinically. Enzyme activation has been observed with various compounds, in particular halo-alcohols and detergents. Several inhibitors provide competitive protection against enzyme inactivation by DL-2-bromo-3-(5-imidazolyl)propionic acid. This enables the dissociation constants for binary enzyme-inhibitor complexes to be determined. NADH protects noncompetitively against inactivation. The presence of some binary and ternary enzyme-NADH complexes is indicated from fluorescence emission spectra, as a shift in the fluorescence maximum and intensity is observed due to their formation.
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Affiliation(s)
- R I Lindstad
- Institute of Biochemistry, University of Oslo, Blindern, Norway
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16
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Lindstad RI, McKinley-McKee JS. Methylglyoxal and the polyol pathway. Three-carbon compounds are substrates for sheep liver sorbitol dehydrogenase. FEBS Lett 1993; 330:31-5. [PMID: 8370454 DOI: 10.1016/0014-5793(93)80913-f] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Methylglyoxal, 1,2-propanediol and glycerol are shown to be substrates for sheep liver sorbitol dehydrogenase. With 1,2-propanediol the enzyme-catalyzed reaction occurs specifically with the R(-)-enantiomer. The maximum velocities and the specificity constants obtained for the three-carbon substrates are considerably lower than those reported previously for sorbitol, and suggest that rate-determination is imposed by catalytic steps other than the enzyme-coenzyme product dissociation. The present findings are discussed in terms of substrate specificity and stereospecificity, and may indicate novel aspects of sorbitol dehydrogenase function in relation to glucose metabolism and diabetic pathogenesis.
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Affiliation(s)
- R I Lindstad
- Biochemical Institute, University of Oslo, Norway
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17
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Niimi T, Yamashita O, Yaginuma T. A cold-inducible Bombyx gene encoding a protein similar to mammalian sorbitol dehydrogenase. Yolk nuclei-dependent gene expression in diapause eggs. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 213:1125-31. [PMID: 8504807 DOI: 10.1111/j.1432-1033.1993.tb17862.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
To facilitate the study of the induction of sorbitol dehydrogenase by acclimation to 5 degrees C in diapause eggs of the silkworm, Bombyx mori, two cDNA libraries from eggs and larval fat bodies were screened with anti-(sorbitol dehydrogenase) serum, and a positive cDNA was cloned from the fat-body cDNA library. 1039 nucleotides determined from the cDNA corresponded to a protein-coding region consisting of 346 amino acids. The missing regions (containing two amino acids at the 5' end and a stop codon at the 3' end) were supplemented with the genome sequence. The deduced amino-acid sequence had 45-47% identity with mammalian sorbitol dehydrogenases. The results led us to conclude that the cDNA for a Bombyx homolog of mammalian sorbitol dehydrogenase was isolated, which was designated as BmSDH. Analyses of Northern hybridization and reverse transcription/polymerase chain reaction showed that the transcript of BmSDH occurred after chilling for 40-50 days when the diapause eggs were exposed to 5 degrees C from two days after oviposition to break the diapause. The changing pattern in the amount of BmSDH transcript was well correlated with those in the activity of sorbitol dehydrogenase and the amount of the enzyme protein in diapause eggs. Further, the transcript of BmSDH was localized in yolk cells. The results indicate that the yolk nuclei-dependent gene expression of BmSDH is induced by acclimation to 5 degrees C in diapause eggs.
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Affiliation(s)
- T Niimi
- Laboratory of Sericultural Science, Faculty of Agriculture, Nagoya University, Japan
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18
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Reiersen H, Sletten K, McKinley-McKee JS. Affinity labelling of sorbitol dehydrogenase from sheep liver with alpha-bromo-beta-(5-imidazolyl)propionic acid. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 211:861-9. [PMID: 8436142 DOI: 10.1111/j.1432-1033.1993.tb17619.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The metal-directed alkylating agent DL-alpha-bromo-beta-(5- imidazolyl)propionic acid (BrImPpOH) is shown to be an affinity-labelling reagent for sheep liver sorbitol dehydrogenase (SDH). As previously found for horse liver alcohol dehydrogenase (ADH), it modifies a cysteine ligand to the active-site zinc. In this case it is selectively incorporated (over 90%) at Cys43 in each of the four polypeptide chains/protomers of sheep liver SDH. Incorporated reagent and residual activity correlated. The first order inactivation constant, K2, and KEI, the dissociation constant for SDH and BrImPpOH, have been determined at different pH. The reactivity of BrImPpOH for SDH is higher than that for horse liver and yeast ADH. The protection of SDH against BrImPpOH inactivation by buffers and other molecules shows some similarities to that with horse liver ADH. However, sheep liver SDH bound BrImPpOH, imidazole and phosphate ions much weaker than liver ADH. The pKa values from the plot of log (k2/KEI) against pH are approximately 7.0 and 8.8-8.9. The former pKa value probably represents ionization of an imidazole group and the latter the zinc/water ionization in SDH. These pKa values are similar to those found for horse liver ADH. They are apparently not noticeably influenced by a second cysteine ligand in liver ADH being replaced by a proposed glutamic acid residue as a ligand to the catalytic zinc in SDH. The plot of logk2 against pH shows pKa values around 7.0 and 9.2 for the SDH-BrImPpOH-complex. The pKa of 7.0 is the same as for log(k2/KEI), and indicates no significant perturbation due to the binding of BrImPpOH to SDH. The pKa around 9.2 indicates perturbation of the zinc/water ionization or the ionization of Cys43.
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Affiliation(s)
- H Reiersen
- Biochemical Institute, University of Oslo, Blindern, Norway
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19
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Lindstad RI, Hermansen LF, McKinley-McKee JS. The kinetic mechanism of sheep liver sorbitol dehydrogenase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1992; 210:641-7. [PMID: 1459146 DOI: 10.1111/j.1432-1033.1992.tb17465.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The relations between the kinetic parameters for both sorbitol oxidation and fructose reduction by sheep liver sorbitol dehydrogenase show that a Theorell-Chance compulsory order mechanism operates from pH 7.4 to 9.9. This is supported by many parallels with the kinetics of horse liver alcohol dehydrogenase, which operates by this classical mechanism. An isotope-exchange study using D-(2H8)sorbitol confirmed the existence of ternary complexes and that, under maximum velocity conditions, their interconversion is not rate-determining. Substrate inhibition at high concentrations of D-sorbitol or D-fructose confirmed rate-determining enzyme--coenzyme product dissociation, slowed by the existence of more stable abortive ternary enzyme-coenzyme product complexes with substrate. The effect of the inhibitor/activator 2,2,2-tribromoethanol showed the existence of enzyme-NAD-CBr3CH2OH complexes inhibiting the first phase of reaction and enzyme-NADH-CBr3CH2OH complexes dissociating more rapidly than the usual rate-determining enzyme-NADH coenzyme product dissociation in the final phase. Inhibition studies with dithiothreitol also confirmed an ordered binding of coenzymes and second substrates to sorbitol dehydrogenase. Neither D-sorbitol nor D-fructose had any effect on enzyme inactivation by the affinity labelling reagent DL-2-bromo-3-(5-imidazolyl)propionic acid, thus giving no evidence for their existence as binary enzyme-substrate complexes. Several alternative polyol substrates for sorbitol dehydrogenase gave the same maximum velocity as sorbitol. This indicated a common rate-limiting binary enzyme-NADH product dissociation and a similarity of mechanism. An enzyme assay for pH 7.0 and 9.9 is given which enables the concentration of sorbitol dehydrogenase to be determined from initial rate measurements of enzyme activity.
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Affiliation(s)
- R I Lindstad
- Institute of Biochemistry, University of Oslo, Blindern, Norway
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20
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Maret W. Novel substrates and inhibitors of human liver sorbitol dehydrogenase. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1990; 284:327-36. [PMID: 2053488 DOI: 10.1007/978-1-4684-5901-2_35] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- W Maret
- Center for Biochemical and Biophysical Sciences, Harvard Medical School, Brigham and Women's Hospital, Boston, MA 02115
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21
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Beier KH, Anderson CD, Anderson BM. Nonpolar interactions in the modification of an essential sulfhydryl of sorbitol dehydrogenase by N-alkylmaleimides. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 997:236-41. [PMID: 2765561 DOI: 10.1016/0167-4838(89)90193-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A series of N-alkylmaleimides varying in chainlength from N-methyl- to N-octylmaleimide inclusive was shown to effectively inactivate sheep liver sorbitol dehydrogenase at pH 7.5 and 25 degrees C. The apparent second-order rate constants for inactivation increased with increasing chainlength of the N-alkylmaleimide used. Positive chainlength effects were also indicated by the Kd values for the N-ethyl and N-heptyl derivatives obtained from studies of the saturation kinetics observed for inactivation of the enzyme at high concentrations of these maleimides. The complete inactivation of sorbitol dehydrogenase was demonstrated to occur through the selective covalent modification of one cysteine residue per subunit of enzyme. The stoichiometry of enzyme inactivation was supported on the one hand by fluorescence titration with fluorescein mercuric acetate of the native and the inactivated enzyme, and, on the other hand, by the simultaneous inactivation of the enzyme with selective modification of one sulfhydryl per subunit by N-[p-(2-benzoxazolyl)phenyl]maleimide. Protection of the enzyme from N-alkylmaleimide inactivation was observed with the binding of NADH, whereas both NAD and sorbitol were ineffective as protecting ligands. Diazotized 3-aminopyridine adenine dinucleotide, in contrast to previous studies of this reagent with yeast alcohol dehydrogenase and rabbit muscle glycerophosphate dehydrogenase, did not function as a site-labeling reagent for sorbitol dehydrogenase.
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Affiliation(s)
- K H Beier
- Department of Biochemistry and Nutrition, Virginia Polytechnic Institute and State University, Blacksburg 24061
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22
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Stephens L, Hawkins PT, Carter N, Chahwala SB, Morris AJ, Whetton AD, Downes PC. L-myo-inositol 1,4,5,6-tetrakisphosphate is present in both mammalian and avian cells. Biochem J 1988; 249:271-82. [PMID: 3342011 PMCID: PMC1148694 DOI: 10.1042/bj2490271] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
When myo-[3H]inositol-prelabelled primary-cultured murine bone-marrow-derived macrophages were challenged with platelet-activating factor (PAF; 200 ng/ml), there was a rapid (2.5-fold at 10 s) rise in the intracellular concentration of D-myo-[3H]inositol 1,4,5-trisphosphate, followed by a rise in myo-[3H]inositol tetrakisphosphate. myo-[3H]Inositol tetrakisphosphate fractions were isolated by high-performance anion-exchange chromatography from myo-[3H]inositol-prelabelled chick erythrocytes and primary-cultured macrophages. In both cases [3H]iditol and [3H]inositol were the only significant products (greater than 90% of recovered radioactivity) after oxidation to completion with periodic acid, reduction with NaBH4 and dephosphorylation with alkaline phosphatase. The presence of [3H]inositol after this procedure is consistent with the occurrence of [3H]inositol 1,3,4,5-tetrakisphosphate in the cell extracts, whereas [3H]iditol could only be derived from D- or L-inositol 1,4,5,6-tetrakisphosphate. When [3H]inositol tetrakisphosphate fractions obtained from (A) unstimulated macrophages, (B) macrophages that had been stimulated with PAF for 40s or (C) chick erythrocytes were subjected to the above procedure, radioactivity was recovered in these polyols in the following proportions: A, 60-90% in iditol, with 10-40% in inositol; B, total radioactivity increased by a factor of 9.8, 94% being recovered in inositol and 8% in iditol; C, 70-80% in iditol and 20-30% in inositol. [3H]Iditol derived from myo-[3H]inositol tetrakisphosphate fractions from macrophages and chick erythrocytes was oxidized to sorbose by L-iditol dehydrogenase (L-iditol:NAD+2-oxidoreductase, 1.1.1.14) at the same rate as authentic L-iditol. D-[14C]Iditol, derived from D-myo-inositol 1,4,5-trisphosphate, was not oxidized by L-iditol dehydrogenase. This result indicates that the [3H]iditol was derived from L-myo-inositol inositol 1,4,5,6-tetrakisphosphate. The data are consistent with rapid PAF-sensitive synthesis of D-myo-[3H]inositol 1,3,4,5-tetrakisphosphate in macrophages, and demonstrate that L-myo-inositol 1,4,5,6-tetrakisphosphate is synthesized in both mammalian and avian cells. The levels of L-myo-[3H]inositol 1,4,5,6-tetrakisphosphate in primary-cultured macrophages are not acutely sensitive to PAF.
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Affiliation(s)
- L Stephens
- Smith Kline & French Research Ltd., Welwyn, Herts., U.K
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23
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Doehlert DC. Ketose reductase activity in developing maize endosperm. PLANT PHYSIOLOGY 1987; 84:830-4. [PMID: 16665530 PMCID: PMC1056678 DOI: 10.1104/pp.84.3.830] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Ketose reductase (NAD-dependent polyol dehydrogenase EC 1.1.1.14) activity, which catalyzes the NADH-dependent reduction of fructose to sorbitol (d-glucitol), was detected in developing maize (Zea mays L.) endosperm, purified 104-fold from this tissue, and partially characterized. Product analysis by high performance liquid chromatography confirmed that the enzyme-catalyzed reaction was freely reversible. In maize endosperm, 15 days after pollination, ketose reductase activity was of the same order of magnitude as sucrose synthase activity, which produces fructose during sucrose degradation. Other enzymes of hexose metabolism detected in maize endosperm were present in activities of only 1 to 3% of the sucrose synthase activity. CaCl(2), MgCl(2), and MnCl(2) stimulated ketose reductase activity 7-, 6-, and 2-fold, respectively, but had little effect on NAD-dependent polyol dehydrogenation (the reverse reaction). The pH optimums for ketose reductase and polyol dehydrogenase reactions were 6.0 and 9.0, respectively. K(m) values were 136 millimolar fructose and 8.4 millimolar sorbitol. The molecular mass of ketose reductase was estimated to be 78 kilodaltons by gel filtration. It is postulated that ketose reductase may function to metabolize some of the fructose produced during sucrose degradation in maize endosperm, but the metabolic fate of sorbitol produced by this reaction is not known.
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Affiliation(s)
- D C Doehlert
- Agricultural Research Service, United States Department of Agriculture, Northern Regional Research Center, 1815 North University Street, Peoria, Illinois 61604
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24
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Porter GF, McGuinness ET. Polyol dehydrogenase: purification. Evidence for multiple forms and some properties of the dominant variant of the horse liver enzyme. PREPARATIVE BIOCHEMISTRY 1987; 17:143-55. [PMID: 3601884 DOI: 10.1080/00327488708062485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Purification of horse-liver polyol dehydrogenase (PDH) on DE52 anion-exchange cellulose reveals the presence of three fractions with enzyme activity. These appear in the breakthrough volume (PDH-3) and the salt gradient (PDH-1, -2) respectively. The major band of activity (greater than approximately 90%) is found in the PDH-2 fraction. A reexamination of sheep-liver polyol dehydrogenase also reveals the presence of three bands of activity, with the dominant fraction (PDH-3) corresponding to the preparation described by Smith (Biochem. J., 83, 135-144, (1962)). The interaction between horse-liver (and sheep-liver) PDH and Blue Sepharose CL-6B is found to be endothermic. This property is utilized in the final purification step. Horse-liver PDH-2 has a molecular/subunit weight of approximately 85,000/approximately 28,000, a Stokes' radius of 3.8 nm, and an isoelectric point of 7.4.
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25
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Chang K, Tomlinson M, Jeffrey JR, Tilton RG, Sherman WR, Ackermann KE, Berger RA, Cicero TJ, Kilo C, Williamson JR. Galactose ingestion increases vascular permeability and collagen solubility in normal male rats. J Clin Invest 1987; 79:367-73. [PMID: 3100575 PMCID: PMC424075 DOI: 10.1172/jci112821] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
In view of the similarity of cataracts and neuropathy in galactose-fed and diabetic rats, the present experiments were undertaken to determine whether consumption of galactose-enriched diets (10, 25, or 50% by weight) also increases collagen crosslinking and permeation of vessels by 125I-albumin analogous to that observed in diabetic rats. The observations in these experiments: demonstrate that consumption of galactose-enriched diets for 3 wk selectively increases 125I-albumin permeation of the same vascular beds affected in diabetic rats and by diabetic vascular disease in humans (i.e., the aorta and vessels in the eye, kidney, sciatic nerve, and new tissue formed in the diabetic milieu); demonstrate that the susceptibility of the vasculature to aldose reductase-linked injury (increased permeability) varies greatly in different tissues; indicate that collagen solubility (crosslinking) changes in galactose-fed rats differ sharply from those in diabetic rats; and provide new evidence that consumption of galactose-enriched diets induces a hypogonadal state in male rats.
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26
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The role of the sorbitol pathway of glucose metabolism in the mechanisms of the therapeutic action of pantethine in experimental diabetes. Pharm Chem J 1986. [DOI: 10.1007/bf00757629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Ditzelmüller G, Kubicek C, Wöhrer W, Röhr M. Xylitol dehydrogenase fromPachysolen tannophilus. FEMS Microbiol Lett 1984. [DOI: 10.1111/j.1574-6968.1984.tb01455.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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28
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O'Brien MM, Schofield PJ, Edwards MR. Polyol-pathway enzymes of human brain. Partial purification and properties of sorbitol dehydrogenase. Biochem J 1983; 211:81-90. [PMID: 6870831 PMCID: PMC1154331 DOI: 10.1042/bj2110081] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Sorbitol dehydrogenase was isolated from human brain and purified 690-fold, giving a final specific activity of 11.1 units/mg of protein. The enzyme preparation was nearly homogeneous, but was unstable at most temperatures. It exhibited a broad pH optimum of 7.5-9.0 in the forward reaction (i.e. sorbitol leads to fructose), and of 7.0 in the reverse reaction (i.e. fructose leads to sorbitol). Substrate-specificity studies demonstrated that the enzyme had the capability to oxidize a wide range of polyols and that the enzyme had a higher affinity for substrates in the forward reaction than in the reverse reaction, e.g. Km for sorbitol was 0.45 mM, and that for fructose was 480 mM. However, the Vmax. was 10 times greater in the reverse reaction. At high concentrations of fructose (500 mM) the enzyme exhibited substrate inhibition in the reverse reaction. The enzyme mechanism was sequential, as determined by the kinetic patterns arising from varying the substrate concentrations. In addition, both fructose and NADH protected the enzyme against thermal inactivation. These findings, together with product-inhibition data, suggested that the mechanism is random rapid equilibrium with two dead-end complexes.
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29
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Burnell JN, Holmes RS. Purification and properties of sorbitol dehydrogenase from mouse liver. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1983; 15:507-11. [PMID: 6852349 DOI: 10.1016/0020-711x(83)90124-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
1. The sorbitol dehydrogenase (L-iditol: NAD oxidoreductase, EC 1.1.1.14) from mouse liver has been purified to homogeneity. 2. The enzyme has a mol. wt of 140,000 and is composed of four identical subunits of mol. wt 35,000. 3. the purified enzyme catalyses both sorbitol oxidation and fructose reduction. 4. It is specific for NAD+ (NADH) and does not function with NADP+ (NADPH). 5. The Michaelis constants for sorbitol, fructose, NAD+ and NADPH are 1.54 and 154 mM, 58.8 and 15 microM, respectively. 6. The enzyme is SH-group reagent sensitive and is strongly inhibited by 1,10-phenanthroline.
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Jeffery J, Cummins L, Carlquist M, Jörnvall H. Properties of sorbitol dehydrogenase and characterization of a reactive cysteine residue reveal unexpected similarities to alcohol dehydrogenases. EUROPEAN JOURNAL OF BIOCHEMISTRY 1981; 120:229-34. [PMID: 7032910 DOI: 10.1111/j.1432-1033.1981.tb05693.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Sorbitol dehydrogenase was characterized as a homogeneous protein on affinity chromatography and ion-exchange chromatography. Tests of stability, sensitivity to inhibitors, and protection by coenzyme suggest that the enzyme has essential cysteine, metal, and probably histidine. The native enzyme has a molecular weight around 140 000 and a subunit around 35 000--40 000, suggesting a tetrameric quaternary structure. Subunits are highly similar if not identical as judged by characterization of one unique 45-residue sequence containing a single reactive cysteine residue. Properties resemble those of mammalian and yeast alcohol dehydrogenases, and the sequence determined for the region around the reactive cysteine residue is homologous to that around one of the zinc-liganding cysteine residues at the active site of horse liver alcohol dehydrogenase. Sorbitol dehydrogenase thus reveals an unexpected relationship to alcohol dehydrogenases, from which ancestral connections and functional mechanisms in this group of enzymes may be further elucidated.
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31
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Bailey JP, Renz C, McGuinness ET. Sorbitol dehydrogenase from horse liver: Purification, characterization and comparative properties. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/0305-0491(81)90407-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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32
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Jeffery J. Kinetic aspects of soluble dehydrogenases requiring nicotinamide coenzymes. EXPERIENTIA. SUPPLEMENTUM 1980; 36:1-39. [PMID: 6987074 DOI: 10.1007/978-3-0348-5419-1_1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Methods for establishing the kinetic mechanisms of dehydrogenase reactions are dealt with in general terms. Examples ranging from relatively simple to obviously complex enzymes, and showing various mechanistic features of interest and importance are discussed.
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33
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Negm FB, Loescher WH. Detection and characterization of sorbitol dehydrogenase from apple callus tissue. PLANT PHYSIOLOGY 1979; 64:69-73. [PMID: 16660917 PMCID: PMC543026 DOI: 10.1104/pp.64.1.69] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Sorbitol dehydrogenase (l-iditol:NAD(+) oxidoreductase, EC 1.1.1.14) has been detected and characterized from apple (Malus domestica cv. Granny Smith) mesocarp tissue cultures. The enzyme oxidized sorbitol, xylitol, l-arabitol, ribitol, and l-threitol in the presence of NAD. NADP could not replace NAD. Mannitol was slightly oxidized (8% of sorbitol). Other polyols that did not serve as substrate were galactitol, myo-inositol, d-arabitol, erythritol, and glycerol. The dehydrogenase oxidized NADH in the presence of d-fructose or l-sorbose. No detectable activity was observed with d-tagatose. NADPH could partially substitute for NADH.Maximum rate of NAD reduction in the presence of sorbitol occurred in tris(hydroxymethyl)aminomethane-HCl buffer (pH 9), or in 2-amino-2-methyl-1,3-propanediol buffer (pH 9.5). Maximum rates of NADH oxidation in the presence of fructose were observed between pH 5.7 and 7.0 with phosphate buffer. Reaction rates increased with increasing temperature up to 60 C. The K(m) for sorbitol and xylitol oxidation were 86 millimolar and 37 millimolar, respectively. The K(m) for fructose reduction was 1.5 molar.Sorbitol oxidation was completely inhibited by heavy metal ions, iodoacetate, p-chloromercuribenzoate, and cysteine. ZnSO(4) (0.25 millimolar) reversed the cysteine inhibition. It is suggested that apple sorbitol dehydrogenase contains sulfhydryl groups and requires a metal ion for full activity.
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Affiliation(s)
- F B Negm
- Department of Horticulture and Landscape Architecture, Washington State University, Pullman, Washington 99164
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Abstract
The effects of oral administration of xylitol on the rate of ethanol elimination and on the ethanol-induced changes in blood concentrations of lactate and pyruvate were studied in seven healthy male subjects. Xylitol (1.0 g/kg body weight) was administered orally and ethanol (0.8 g/kg body weight) intravenously. In the control experiments glucose was given instead of xylitol. Xylitol had no significant effect on the rate of ethanol elimination or on the ethanol-induced increase in the blood lactate concentration. The ethanol-induced changes in the lactate/pyruvate ratio were not affected by xylitol. It is suggested that the ineffectiveness of xylitol is due to its low concentration in the liver after oral administration. Ethanol induced a 5--10 fold increase in the blood concentration of xylitol. This is most probably due to inhibition of xylitol oxidation in the liver by the ethanol-induced reduction in the hepatic redox state. The clinical significance of this finding is unknown.
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36
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Holmes RS, Jones JT, Peters J. Genetic variation, cellular distribution and ontogeny of sorbitol dehydrogenase and alcohol dehydrogenase isozymes in male reproductive tissues of the mouse. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1978; 206:279-88. [PMID: 722274 DOI: 10.1002/jez.1402060219] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cellulose acetate zymograms of alcohol dehydrogenase (ADH) and sorbitol dehydrogenase (SDH) extracted from male reproductive tissues of inbred mice were examined. ADH isozymes were differentially distributed in these tissues of C3H/He mice; ADH-B2 was observed in all tissues and testis cellular preparations examined; ADH-C2 was localized predominantly in the epididymis but was also present in the seminal vesicles, coagulating gland, and prostate gland. SDH was broadly distributed in these tissues but exhibited highest activities in the seminal vesicles, coagulating glands, and germinal cells of mature testes. Genetic variants for ADH-C2 and SDH provided evidence for (1) the identity of a second form of SDH in epididymis with ADH-C2; (2) the genetic identity of kidney, seminal vesicle, and testis SDH; and (3) the gentic identity of stomach and epididymal ADH-C2. Developmental changes in testis and epididymal ADH isozymes during maturation were examined. ADH-C2 appeared in the mature epididymis whereas ADH-B2 exhibited no major changes in activity in testis and epididymis during development.
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37
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Leissing N, McGuinness ET. Rapid affinity purification and properties of rat liver sorbitol dehydrogenase. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 524:254-61. [PMID: 667078 DOI: 10.1016/0005-2744(78)90162-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A 23-h affinity chromatography purification procedure for sorbitol dehydrogenase (L-iditol:NADl-oxidoreductase, EC 1.1.1.14) prepared from freshly excised rat liver has been developed that resulted in an 18% yield of an apparently homogeneous preparation (purification = 439-fold). The molecular weight of the enzyme was approx. 96 000. The enzyme was specific for NAD+ (NADH), but had no requirement for NADP+ (NADPH). The purified preparation shows significant activity with structurally related polyols and ketoses. Km values for sorbitol and fructose are 0.35 and 110 mM (at pH 7.1), respectively.
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Walsall EP, Lyons SA, Metzger RP. A comparison of selected physical properties of hepatic sorbitol dehydrogenases [L-iditol: NAD oxidoreductases] from four mammalian species. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1978; 59:213-8. [PMID: 318236 DOI: 10.1016/0305-0491(78)90249-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
1. The sorbitol dehydrogenases [L-iditol: NAD oxidoreductase] from livers of cow, man, rat and sheep each possess molecular weights of about 140,000. The beef, rat and sheep liver enzymes are composed of subunits of molecular weight 40,000. 2. The sorbitol dehydrogenases from livers of these four species each possess an isoelectric point of 7.3. 3. The four enzyme preparations show identical mobilities upon disc-gel electrophoresis and yield a single band of enzymic activity. 4. Sorbitol dehydrogenase activity is activated by the presence of ampholines or by increasing ionic strengths, with maximal activation at about 0.5 M salt concentration. These factors may cause the Km for NAD to be lowered.
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Affiliation(s)
- E P Walsall
- Department of Chemistry, San Diego State University, CA 92182
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39
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Studies on sorbitol dehydrogenase from the parasitic nematode larvae ofPhocanema decipiens. Parasitol Res 1978. [DOI: 10.1007/bf00927152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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40
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Rehg JE, Torack RM. Partial purification and characterization of sorbitol dehydrogenase from rat brain. J Neurochem 1977; 28:655-60. [PMID: 16089 DOI: 10.1111/j.1471-4159.1977.tb10438.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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41
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43
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Youdim MB, Woods HF. The influence of tissue environment on the rates of metabolic processes and the properties of enzymes. Biochem Pharmacol 1975; 24:317-23. [PMID: 1125037 DOI: 10.1016/0006-2952(75)90212-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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44
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45
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Alizade MA, Bressler R, Brendel K. Stereochemistry of the L-iditol dehydrogenase catalyzed hydrogen transfer to NAD. BIOCHIMICA ET BIOPHYSICA ACTA 1974; 370:354-7. [PMID: 4374239 DOI: 10.1016/0005-2744(74)90096-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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46
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Beutler E, Guinto E. The reduction of glyceraldehyde by human erythrocytes. L-hexonate dehydrogenase activity. J Clin Invest 1974; 53:1258-64. [PMID: 4825223 PMCID: PMC302612 DOI: 10.1172/jci107672] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Incubation of red cell suspensions with D-glyceraldehyde resulted in disappearance of glyceraldehyde and appearance of glycerol. Concomitantly, there was an increase of CO(2) formation from glucose. This indicated that the reduction of glyceraldehyde to glycerol occurred through a NADPH-linked system. Studies in hemolysates revealed the presence of an enzyme with the capacity to catalyze the reduction of glyceraldehyde to glycerol by NADPH. This enzyme was partially purified by DEAE chromatography. The elution pattern of the enzyme and its kinetic characteristics indicated that the enzyme was L-hexonate dehydrogenase (L-gulonate: NADP oxidoreductase, EC 1.1.1.19), not aldose reductase (Alditol: NADP oxidoreductase, EC 1.1.1.21), which had previously been thought present in erythrocytes. The reduction of glyceraldehyde to glycerol is one of a number of pathways for the metabolism of glyceraldehyde that have been found in red cells and/or other mammalian tissues.
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Morrison AD, Clements RS, Winegrad AI. Effects of elevated glucose concentrations on the metabolism of the aortic wall. J Clin Invest 1972; 51:3114-23. [PMID: 4640951 PMCID: PMC332993 DOI: 10.1172/jci107138] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The effects of elevated glucose concentrations on the metabolism of the aortic wall were examined in a preparation of tubular segments of rabbit descending thoracic aorta comprised of intima and media only. Increased medium glucose concentrations (20-50 mm) resulted in increased aortic sorbitol and fructose concentrations and an increased rate of fructose release into the medium. This increased flux through the polyol pathway can be explained as a consequence both of an increased free intracellular glucose concentration and of the kinetic characteristics of the alditol: NADP oxidoreductase and the l-iditol: NAD oxidoreductase isolated and partially purified from rabbit thoracic aorta. Incubation with elevated glucose concentrations for 2 or more hr was also associated with a significant increase in the water content of the tissue without a significant increase in the inulin space. The oxygen uptake of the tissues incubated with elevated glucose concentrations was significantly reduced; this appears to result from a limitation imposed by oxygen diffusion at physiological oxygen tensions. A compensatory increase in glycolysis and an increase in the aortic lactate/pyruvate concentration ratio were also observed. The oxygen uptake and lactate production of tissue incubated with 50 mm glucose could be preserved at rates observed in tissue incubated with a physiological glucose concentration by the addition of 40 mm mannitol to the medium. Aortic intima and media from alloxan-diabetic rabbits also exhibit an increased water content and a decreased rate of oxygen uptake. These observations suggest that elevated ambient glucose concentrations result in significant alterations in the metabolism of aortic intima and media.
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