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Kano A, Gomi K, Yamasaki-Kokudo Y, Satoh M, Fukumoto T, Ohtani K, Tajima S, Izumori K, Tanaka K, Ishida Y, Tada Y, Nishizawa Y, Akimitsu K. A rare sugar, d-allose, confers resistance to rice bacterial blight with upregulation of defense-related genes in Oryza sativa. PHYTOPATHOLOGY 2010; 100:85-90. [PMID: 19968553 DOI: 10.1094/phyto-100-1-0085] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We investigated responses of rice plant to three rare sugars, d-altrose, d-sorbose, and d-allose, due to establishment of mass production methods for these rare sugars. Root growth and shoot growth were significantly inhibited by d-allose but not by the other rare sugars. A large-scale gene expression analysis using a rice microarray revealed that d-allose treatment causes a high upregulation of many defense-related, pathogenesis-related (PR) protein genes in rice. The PR protein genes were not upregulated by other rare sugars. Furthermore, d-allose treatment of rice plants conferred limited resistance of the rice against the pathogen Xanthomonas oryzae pv. oryzae but the other tested sugars did not. These results indicate that d-allose has a growth inhibitory effect but might prove to be a candidate elicitor for reducing disease development in rice.
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Affiliation(s)
- Akihito Kano
- Faculty of Agriculture, Gene research Center and rare Sugar Research Center , Kagawa University, Miki , Kagawa, Japan
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52
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Jung J, Yeom SJ, Kim J, Kim JK, Natarajan S, Ahn YJ, Lim SB, Oh DK, Kang LW. Overexpression, crystallization and preliminary X-ray crystallographic analysis of D-ribose-5-phosphate isomerase from Clostridium thermocellum. Acta Crystallogr Sect F Struct Biol Cryst Commun 2009; 65:1141-4. [PMID: 19923736 DOI: 10.1107/s1744309109038093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 09/21/2009] [Indexed: 11/10/2022]
Abstract
Rare sugars are used for many industrial and medical purposes and are produced by the interconversion between aldoses and ketoses catalyzed by sugar and sugar-phosphate isomerases. Recently, Clostridium thermocellum d-ribose-5-phosphate isomerase (CTRPI), an aldose-ketose isomerase, was cloned in order to synthesize d-allose and its substrate specificity was further characterized for industrial usage. CTRPI has a novel substrate specificity that differs from those of other isomerases, which have broad substrate specificities. CTRPI prefers aldose substrates such as l-talose, d-ribose and d-allose. CTRPI was purified and crystallized in order to determine its three-dimensional structure and thus to elucidate its enzymatic reaction mechanism and understand its substrate specificity. The crystal belonged to the trigonal space group P3(2)21, with unit-cell parameters a = b = 69.5, c = 154.4 angstrom, and diffracted to 1.9 angstrom resolution. According to Matthews coefficient calculations, the crystallographic structure consists of a dimer in the asymmetric unit, with a V(M) of 3.2 angstrom(3) Da(-1) and a solvent content of 61.7%.
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Affiliation(s)
- Junho Jung
- Department of Advanced Technology Fusion, Konkuk University, Hwayang-dong, Gwangjin-gu, Seoul, Republic of Korea
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53
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Analysis of the inhibitory mechanism of d-allose on MOLT-4F leukemia cell proliferation. J Biosci Bioeng 2009; 107:562-8. [DOI: 10.1016/j.jbiosc.2008.12.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 12/23/2008] [Indexed: 11/20/2022]
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54
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Yoon RY, Yeom SJ, Park CS, Oh DK. Substrate specificity of a glucose-6-phosphate isomerase from Pyrococcus furiosus for monosaccharides. Appl Microbiol Biotechnol 2009; 83:295-303. [PMID: 19159927 DOI: 10.1007/s00253-009-1859-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Revised: 01/03/2009] [Accepted: 01/05/2009] [Indexed: 11/25/2022]
Abstract
We purified recombinant glucose-6-phosphate isomerase from Pyrococcus furiosus using heat treatment and Hi-Trap anion-exchange chromatography with a final specific activity of 0.39 U mg(-1). The activity of the glucose-6-phosphate isomerase for L: -talose isomerization was optimal at pH 7.0, 95 degrees C, and 1.5 mM Co(2+). The half-lives of the enzyme at 65 degrees C, 75 degrees C, 85 degrees C, and 95 degrees C were 170, 41, 19, and 7.9 h, respectively. Glucose-6-phosphate isomerase catalyzed the interconversion between two different aldoses and ketose for all pentoses and hexoses via two isomerization reactions. This enzyme has a unique activity order as follows: aldose substrates with hydroxyl groups oriented in the same direction at C2, C3, and C4 > C2 and C4 > C2 and C3 > C3 and C4. L: -Talose and D: -ribulose exhibited the most preferred substrates among the aldoses and ketoses, respectively. L: -Talose was converted to L: -tagatose and L: -galactose by glucose-6-phosphate isomerase with 80% and 5% conversion yields after about 420 min, respectively, whereas D: -ribulose was converted to D: -ribose and D: -arabinose with 53% and 8% conversion yields after about 240 min, respectively.
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Affiliation(s)
- Ran-Young Yoon
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 143-701, South Korea
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55
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Yoon RY, Yeom SJ, Kim HJ, Oh DK. Novel substrates of a ribose-5-phosphate isomerase from Clostridium thermocellum. J Biotechnol 2009; 139:26-32. [PMID: 18984017 DOI: 10.1016/j.jbiotec.2008.09.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 09/16/2008] [Accepted: 09/23/2008] [Indexed: 10/21/2022]
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56
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Fujiwara T, Hayashi M. Efficient Synthesis of Rare Sugar d-Allal via Reversal of Diastereoselection in the Reduction of Protected 1,5-Anhydrohex-1-en-3-uloses: Protecting Group Dependence of the Stereoselection. J Org Chem 2008; 73:9161-3. [DOI: 10.1021/jo801596q] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Takashi Fujiwara
- Department of Chemistry, Graduate School of Science, Kobe University, Nada, Kobe 657-8501
| | - Masahiko Hayashi
- Department of Chemistry, Graduate School of Science, Kobe University, Nada, Kobe 657-8501
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57
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Rare sugar d-allose induces programmed cell death in hormone refractory prostate cancer cells. Apoptosis 2008; 13:1121-34. [DOI: 10.1007/s10495-008-0232-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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58
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Tannuri ACA, Tannuri U, Wakamatsu A, Mello ES, Coelho MCM, Dos Santos NASR. Effect of the immunosuppressants on hepatocyte proliferation and apoptosis in a young animal model of liver regeneration: an immunohistochemical study using tissue microarrays. Pediatr Transplant 2008; 12:40-6. [PMID: 18186887 DOI: 10.1111/j.1399-3046.2007.00766.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Hepatocyte proliferation and apoptosis (programmed cell death) occur during the liver parenchyma regeneration and the liver size modeling is mainly controlled by hepatocyte apoptosis. The purpose of the present study was to verify the influence of immunosuppressant drugs on these phenomena by utilizing tissue microarray techniques. Thirty-six weaning rats (age 21-23 days, weight 30-50 g) were divided into six groups: control, sham, hepatectomy, hepatectomy plus solumedrol, hepatectomy plus CsA, and hepatectomy plus Tac. The animals were killed one day after hepatectomy, and the remnant livers were weighed and harvested for tissue microarray sections. Liver cell proliferation was evaluated by staining for PCNA and apoptosis was detected by the TUNEL method. It was verified that CsA promoted a decrease in the liver weight, Tac and CsA decreased the proliferation index of hepatocytes, and glucocorticoid had no significant effects. The apoptosis index was not altered by hepatectomy or immunosuppressants. Our data indicate that, in the growing rat, CsA and Tac have negative effects on hepatocyte proliferation and have no effect on the hepatocyte apoptosis.
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59
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Tannuri U, Tannuri ACA, Coelho MCA, Mello ES, dos Santos ASR. Effect of the immunosuppressants on hepatocyte cells proliferation and apoptosis during liver regeneration after hepatectomy - molecular studies. Pediatr Transplant 2008; 12:73-79. [PMID: 18320611 DOI: 10.1111/j.1399-3046.2007.00801.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The regeneration and remodeling of the transplanted liver is the result of hepatocyte proliferation and apoptosis (programmed cell death). The purpose of this study was to verify the influence of immunosuppressants on the expression levels of genes: IL-6 (regulator of hepatocyte proliferation), pro-apoptotic (Bak and Bax) and anti-apoptotic (Bcl-Xl and Bcl-2). 36 newborn suckling rats (age 5-7 days, weight 6-10 g) were divided into four groups: hepatectomy, hepatectomy plus methylprednisolone, hepatectomy plus CsA and hepatectomy plus Tac. The same experiments were performed in 24 weaning rats (age 21-23 days, weight 30-50 g). The animals were killed one day after the hepatectomy and the remnant livers were analyzed. The livers of all animals exhibited histological changes of liver regeneration. The immunosuppressants did not promote any alteration on IL-6 gene expression levels. Methylprednisolone and CsA increased the expression levels of Bak gene in newborn rats. However, methylprednisolone and Tac promoted increased expression levels of Bcl-2 in all groups. We hypothesize that these effects explain the efficacy of these drugs on the treatment of acute and chronic liver rejection as the expression of Bcl-2 in cholangiocytes is decreased as a consequence of bile duct lesions
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Affiliation(s)
- Uenis Tannuri
- University of São Paulo Medical School, São Paulo, Brazil.
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60
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Sui L, Nomura R, Dong Y, Yamaguchi F, Izumori K, Tokuda M. Cryoprotective effects of d-allose on mammalian cells. Cryobiology 2007; 55:87-92. [PMID: 17645876 DOI: 10.1016/j.cryobiol.2007.05.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 05/26/2007] [Accepted: 05/30/2007] [Indexed: 10/23/2022]
Abstract
D-allose, an aldo-hexose, is a rare sugar whose biological functions remain largely unclear. Recently, we demonstrated a novel inhibitory effect of D-allose on production of reactive oxygen species (ROS). Here, we focused on investigating cryoprotective effects of D-allose on cell viability. Mammalian cell lines including OVCAR-3 (human ovarian cancer), HeLa (human cervical cancer), HaCaT (human skin keratinocytes), HDF (human dermal fibroblasts) and NIH3T3 (murine fibroblasts) cells were frozen at -80 degrees C in culture media with various D-allose concentrations. Cells were allowed to recover for 24 h, 1 week or 1 month prior to survival assessment using the trypan blue dye exclusion test, when cell proliferation was evaluated by MTT assay. A beneficial protective role of D-allose on cell survival was found, similar to that of trehalose (disaccharide of glucose), a recognized cryoprotectant. The results suggest that D-allose as a sole additive may provide effective protection for mammalian cells during freezing. Practical studies now need to be performed with D-allose, for example to determine optimal freezing protocols and explore potential for preservation of tissues or organs at non-freezing temperatures.
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Affiliation(s)
- Li Sui
- Department of Cell Physiology, Faculty of Medicine, Kagawa University, Kagawa, Japan; Kagawa Industry Support Foundation, Kagawa, Japan
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61
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Park HY, Park CS, Kim HJ, Oh DK. Substrate specificity of a galactose 6-phosphate isomerase from Lactococcus lactis that produces d-allose from d-psicose. J Biotechnol 2007; 132:88-95. [PMID: 17868944 DOI: 10.1016/j.jbiotec.2007.08.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Revised: 07/27/2007] [Accepted: 08/09/2007] [Indexed: 10/22/2022]
Abstract
We purified recombinant galactose 6-phosphate isomerase (LacAB) from Lactococcus lactis using HiTrap Q HP and Phenyl-Sepharose columns. The purified LacAB had a final specific activity of 1.79units/mg to produce d-allose. The molecular mass of native galactose 6-phosphate isomerase was estimated at 135.5kDa using Sephacryl S-300 gel filtration, and the enzyme exists as a hetero-octamer of LacA and LacB subunits. The activity of galactose 6-phosphate isomerase was maximal at pH 7.0 and 30 degrees C, and enzyme activity was independent of metal ions. When 100g/L of d-psicose was used as the substrate, 25g/L of d-allose and 13g/L of d-altrose were simultaneously produced at pH 7.0 and 30 degrees C after 12h of incubation. The enzyme had broad specificity for various aldoses and ketoses. The interconversion of sugars with the same configuration except at the C2 position was driven by using a large amount of enzyme in extended reactions. The interconversion occurred via two isomerization reactions, i.e., the interconversion of d-allose<-->d-psicose<-->d-altrose, and d-allose to d-psicose reaction was faster than d-altrose to d-psicose reaction.
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Affiliation(s)
- Ha-Young Park
- Department of Bioscience and Biotechnology, Konkuk University, Seoul 143-701, Republic of Korea
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62
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Murao K, Yu X, Cao WM, Imachi H, Chen K, Muraoka T, Kitanaka N, Li J, Ahmed RAM, Matsumoto K, Nishiuchi T, Tokuda M, Ishida T. D-Psicose inhibits the expression of MCP-1 induced by high-glucose stimulation in HUVECs. Life Sci 2007; 81:592-9. [PMID: 17655880 DOI: 10.1016/j.lfs.2007.06.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Revised: 06/06/2007] [Accepted: 06/24/2007] [Indexed: 02/02/2023]
Abstract
Monocyte chemoattractant protein-1 (MCP-1) is a 76-amino-acid chemokine thought to be the major chemotactic factor for monocytes. MCP-1 is found in macrophage-rich areas of atherosclerotic lesions. Recent report indicates that MCP-1 is induced by glucose-stimulation, raising the important link between diabetes mellitus and atherosclerosis. One of the rare sugars, d-psicose (d-ribo-2-hexulose) is present in small quantities in commercial carbohydrate complexes, however the physiological functions of d-psicose have not been evaluated. In this study, we examined the effects of d-psicose on MCP-1 expression in human umbilical vein endothelial cells (HUVECs). Results showed that MCP-1 mRNA and protein were stimulated following exposure to 22.4 mM glucose. Transcriptional activity of MCP-1 promoter paralleled endogenous expression of the gene and this activity was dependent on the dose of d-glucose. d-Psicose inhibited these effects. Next we used inhibitors of selected signal transduction pathways to show that high-glucose (HG) stimulated MCP-1 promoter activity was sensitive to p38-Mitogen-Activated Protein Kinase (p38-MAPK) pathway inhibitor. As expected, a dominant-negative p38-MAPK abolished the stimulatory effect of HG on the promoter activity. To incubate the cells with HG and d-psicose reduced the activation of p38-MAPK. Together, these results indicate that the d-psicose suppression of HG induced MCP-1 expression is mediated in part by inhibition of the p38-MAPK pathway and raise the possibility that d-psicose may be of therapeutic value in the treatment of diseases such as atherosclerosis.
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Affiliation(s)
- Koji Murao
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan.
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63
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Park CS, Yeom SJ, Kim HJ, Lee SH, Lee JK, Kim SW, Oh DK. Characterization of ribose-5-phosphate isomerase of Clostridium thermocellum producing D-allose from D-psicose. Biotechnol Lett 2007; 29:1387-91. [PMID: 17484020 DOI: 10.1007/s10529-007-9393-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 04/03/2007] [Accepted: 04/30/2007] [Indexed: 10/23/2022]
Abstract
The rpiB gene, encoding ribose-5-phosphate isomerase (RpiB) from Clostridium thermocellum, was cloned and expressed in Escherichia coli. RpiB converted D-psicose into D-allose but it did not convert D-xylose, L-rhamnose, D-altrose or D-galactose. The production of D-allose by RpiB was maximal at pH 7.5 and 65 degrees C for 30 min. The half-lives of the enzyme at 50 degrees C and 65 degrees C were 96 h and 4.7 h, respectively. Under stable conditions of pH 7.5 and 50 degrees C, 165 g D-allose l(-1 ) was produced without by-products from 500 g D-psicose l(-1) after 6 h.
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Affiliation(s)
- Chang-Su Park
- Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, 143-701, Korea
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64
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Chavira M, Cao N, Le K, Riar T, Moradshahi N, McBride M, Lux R, Shi W. Beta-D-Allose inhibits fruiting body formation and sporulation in Myxococcus xanthus. J Bacteriol 2006; 189:169-78. [PMID: 17056749 PMCID: PMC1797229 DOI: 10.1128/jb.00792-06] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Myxococcus xanthus, a gram-negative soil bacterium, responds to amino acid starvation by entering a process of multicellular development which culminates in the assembly of spore-filled fruiting bodies. Previous studies utilizing developmental inhibitors (such as methionine, lysine, or threonine) have revealed important clues about the mechanisms involved in fruiting body formation. We used Biolog phenotype microarrays to screen 384 chemicals for complete inhibition of fruiting body development in M. xanthus. Here, we report the identification of a novel inhibitor of fruiting body formation and sporulation, beta-d-allose. beta-d-Allose, a rare sugar, is a member of the aldohexose family and a C3 epimer of glucose. Our studies show that beta-d-allose does not affect cell growth, viability, agglutination, or motility. However, beta-galactosidase reporters demonstrate that genes activated between 4 and 14 h of development show significantly lower expression levels in the presence of beta-d-allose. Furthermore, inhibition of fruiting body formation occurs only when beta-d-allose is added to submerged cultures before 12 h of development. In competition studies, high concentrations of galactose and xylose antagonize the nonfruiting response to beta-d-allose, while glucose is capable of partial antagonism. Finally, a magellan-4 transposon mutagenesis screen identified glcK, a putative glucokinase gene, required for beta-d-allose-mediated inhibition of fruiting body formation. Subsequent glucokinase activity assays of the glcK mutant further supported the role of this protein in glucose phosphorylation.
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Affiliation(s)
- Marielena Chavira
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA 90095-1668, USA
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65
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Oh DK, Kim NH, Kim HJ, Park CS, Kim SW, Ko M, Park BW, Jung MH, Yoon KH. d-Psicose production from d-fructose using an isolated strain, Sinorhizobium sp. World J Microbiol Biotechnol 2006. [DOI: 10.1007/s11274-006-9265-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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66
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Afach G, Kawanami Y, Kato-Noguchi H, Izumori K. Practical production of 6-O-octanoyl-D-allose and its biological activity on plant growth. Biosci Biotechnol Biochem 2006; 70:2010-2. [PMID: 16926519 DOI: 10.1271/bbb.60150] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The transesterification of D-allose (the C-3 epimer of D-glucose) with vinyl octanoate using Candida antarctica lipase in tetrahydrofuran proceeded with high regioselectivity to produce 6-O-octanoyl-D-allose with nearly complete conversion. The growth-inhibiting activity of 6-O-octanoyl-D-allose on lettuce seedlings was about 6-fold greater than that of D-allose.
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Affiliation(s)
- Ghanwa Afach
- Department of Biochemistry and Food Science, Faculty of Agriculture, Kagawa University, Japan
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67
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Kim HJ, Hyun EK, Kim YS, Lee YJ, Oh DK. Characterization of an Agrobacterium tumefaciens D-psicose 3-epimerase that converts D-fructose to D-psicose. Appl Environ Microbiol 2006; 72:981-5. [PMID: 16461638 PMCID: PMC1392948 DOI: 10.1128/aem.72.2.981-985.2006] [Citation(s) in RCA: 146] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The noncharacterized gene previously proposed as the D-tagatose 3-epimerase gene from Agrobacterium tumefaciens was cloned and expressed in Escherichia coli. The expressed enzyme was purified by three-step chromatography with a final specific activity of 8.89 U/mg. The molecular mass of the purified protein was estimated to be 132 kDa of four identical subunits. Mn2+ significantly increased the epimerization rate from D-fructose to D-psicose. The enzyme exhibited maximal activity at 50 degrees C and pH 8.0 with Mn2+. The turnover number (k(cat)) and catalytic efficiency (k(cat)/Km) of the enzyme for D-psicose were markedly higher than those for d-tagatose, suggesting that the enzyme is not D-tagatose 3-epimerase but D-psicose 3-epimerase. The equilibrium ratio between D-psicose and D-fructose was 32:68 at 30 degrees C. D-Psicose was produced at 230 g/liter from 700-g/liter D-fructose at 50 degrees C after 100 min, corresponding to a conversion yield of 32.9%.
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Affiliation(s)
- Hye-Jung Kim
- Department of Bioscience and Biotechnology, Sejong University, Seoul 143-747, South Korea
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68
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Chemical properties and antioxidative activity of glycated α-lactalbumin with a rare sugar, -allose, by Maillard reaction. Food Chem 2006. [DOI: 10.1016/j.foodchem.2005.01.033] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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69
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Hossain MA, Wakabayashi H, Izuishi K, Okano K, Yachida S, Tokuda M, Izumori K, Maeta H. Improved microcirculatory effect of d-allose on hepatic ischemia reperfusion following partial hepatectomy in cirrhotic rat liver. J Biosci Bioeng 2006; 101:369-71. [PMID: 16716947 DOI: 10.1263/jbb.101.369] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Accepted: 01/13/2006] [Indexed: 11/17/2022]
Abstract
D-allose, one of the rare sugars produced from D-psicose, has been shown to be effective against reperfusion injury after ischemia and partial hepatectomy in cirrhotic rat liver by improving remnant liver blood flow and survival rates, and decreasing liver enzyme levels and liver tissue injury levels. These findings demand further study of the clinical implications of this sugar in view to the advancing fields of liver surgery and transplantation.
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70
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Menavuvu BT, Poonperm W, Leang K, Noguchi N, Okada H, Morimoto K, Granström TB, Takada G, Izumori K. Efficient biosynthesis of d-allose from d-psicose by cross-linked recombinant l-rhamnose isomerase: Separation of product by ethanol crystallization. J Biosci Bioeng 2006; 101:340-5. [PMID: 16716943 DOI: 10.1263/jbb.101.340] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 01/24/2006] [Indexed: 11/17/2022]
Abstract
Mass production of a rare aldohexose D-allose from D-psicose was achieved in a batch reaction by crude recombinant L-rhamnose isomerase (L-RhI) cross-linked with glutaraldehyde. The D-psicose substrate was, in turn, mass produced from a naturally abundant ketohexose D-fructose by immobilized recombinant D-tagatose 3-epimerase (D-TE). At an equilibrium state, 25% of D-psicose was isomerized to D-allose, that is, 25 g of D-allose was obtained from 100 g of D-psicose. The D-allose product was easily separated and crystallized from the reaction mixture that contains 25%D-allose, 8%D-altrose and 67%D-psicose using ethanol. Empirically, approximately 338 g, that is, 90% of a theoretical overall yield for the purification of pure D-allose crystals was produced from 1.5 kg of D-psicose within 30 d using a constructed bioreactor. The cross-linked enzyme had an operative half-life of two months after repeated usages.
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Affiliation(s)
- Buetusiwa Thomas Menavuvu
- Department of Biochemistry and Food Science, Faculty of Agriculture and Rare Sugar Research Center, Kagawa University, Miki-cho, Kagawa 761-0795, Japan
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