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Production of thermostable endo-1,5-α-L-arabinanase in Pichia pastoris for enzymatically releasing functional oligosaccharides from sugar beet pulp. Appl Microbiol Biotechnol 2019; 104:1595-1607. [PMID: 31879825 DOI: 10.1007/s00253-019-10238-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/21/2019] [Accepted: 11/04/2019] [Indexed: 12/13/2022]
Abstract
Sugar beet pulp is an agricultural processing residue that is a rich source of the cell wall polysaccharide arabinan. Functional oligosaccharides, specifically feruloylated arabino-oligosaccharides (FAOs), can be isolated from sugar beet pulp through selective action by endo-arabinanase (glycoside hydrolase family 43). This study aimed to develop yeast (Pichia pastoris) as an efficient, eukaryotic platform to produce a thermophilic endo-1,5-α-L-arabinanase (TS-ABN) for extracting FAOs from sugar beet pulp. Recombinant TS-ABN was secreted into yeast culture medium at a yield of ~ 80 mg/L, and the protein exhibited specific enzyme activity, pH and temperature optimum, and thermostability comparable to those of the native enzyme. Treatment of sugar beet pulp with Pichia-secreted TS-ABN released FAOs recovered by hydrophobic chromatography at 1.52% (w/w). The isolated FAOs averaged seven arabinose residues per ferulic acid, and treatment of T84 human colon epithelial cells significantly increased expression of two key tight junction-related proteins-zonula occludens-1 and occludin-in a dose-dependent manner. This research establishes a biochemical platform for utilizing sugar beet pulp to produce value-added bioproducts with potential nutraceutical applications.
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Park JM, Jang MU, Kang JH, Kim MJ, Lee SW, Song YB, Shin CS, Han NS, Kim TJ. Detailed modes of action and biochemical characterization of endo-arabinanase from Bacillus licheniformis DSM13. J Microbiol 2012; 50:1041-6. [PMID: 23274993 DOI: 10.1007/s12275-012-2489-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 09/19/2012] [Indexed: 11/25/2022]
Abstract
An endo-arabinanase (BLABNase) gene from Bacillus licheniformis DSM13 was cloned and expressed in Escherichia coli, and the biochemical properties of its encoded enzyme were characterized. The BLABNase gene consists of a single open reading frame of 987 nucleotides that encodes 328 amino acids with a predicted molecular mass of about 36 kDa. BLABNase exhibited the highest activity against debranched α-(1,5)-arabinan in 50 mM sodium acetate buffer (pH 6.0) at 55°C. Enzymatic characterization revealed that BLABNase hydrolyzes debranched or linear arabinans with a much higher activity than branched arabinan from sugar beet. Enzymatic hydrolysis pattern analyses demonstrated BLABNase to be a typical endo-(1,5)-α-S-arabinanase (EC 3.2.1.99) that randomly cleaves the internal α-(1,5)-linked L-arabinofuranosyl residues of a branchless arabinan backbone to release arabinotriose mainly, although a small amount of arabino-oligosaccharide intermediates is also liberated. Our results indicated that BLABNase acts preferentially along with the oligosaccharides longer than arabinopentaose, thus enabling the enzymatic production of various arabino-oligosaccharides.
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Affiliation(s)
- Jung-Mi Park
- Department of Food Science and Technology, Chungbuk National University, Cheongju 361-763, Republic of Korea
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Akel E, Metz B, Seiboth B, Kubicek CP. Molecular regulation of arabinan and L-arabinose metabolism in Hypocrea jecorina (Trichoderma reesei). EUKARYOTIC CELL 2009; 8:1837-44. [PMID: 19801419 PMCID: PMC2794218 DOI: 10.1128/ec.00162-09] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Accepted: 09/25/2009] [Indexed: 11/20/2022]
Abstract
Hypocrea jecorina (anamorph: Trichoderma reesei) can grow on plant arabinans by the aid of secreted arabinan-degrading enzymes. This growth on arabinan and its degradation product L-arabinose requires the operation of the aldose reductase XYL1 and the L-arabinitol dehydrogenase LAD1. Growth on arabinan and L-arabinose is also severely affected in a strain deficient in the general cellulase and hemicellulase regulator XYR1, but this impairment can be overcome by constitutive expression of the xyl1 encoding the aldose reductase. An inspection of the genome of H. jecorina reveals four genes capable of degrading arabinan, i.e., the alpha-L-arabinofuranosidase encoding genes abf1, abf2, and abf3 and also bxl1, which encodes a beta-xylosidase with a separate alpha-L-arabinofuranosidase domain and activity but no endo-arabinanase. Transcriptional analysis reveals that in the parent strain QM9414 the expression of all of these genes is induced by L-arabinose and to a lesser extent by L-arabinitol and absent on D-glucose. Induction by L-arabinitol, however, is strongly enhanced in a Deltalad1 strain lacking L-arabinitol dehydrogenase activity and severely impaired in an aldose reductase (Deltaxyl1) strain, suggesting a cross talk between L-arabinitol and the aldose reductase XYL1 in an alpha-L-arabinofuranosidase gene expression. Strains bearing a knockout in the cellulase regulator xyr1 do not show any induction of abf2 and bxl1, and this phenotype cannot be reverted by constitutive expression of xyl1. The loss of function of xyr1 has also a slight effect on the expression of abf1 and abf3. We conclude that the expression of the four alpha-L-arabinofuranosidases of H. jecorina for growth on arabinan requires an early pathway intermediate (L-arabinitol or L-arabinose), the first enzyme of the pathway XYL1, and in the case of abf2 and bxl1 also the function of the cellulase regulator XYR1.
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Affiliation(s)
- Eda Akel
- Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
| | - Benjamin Metz
- Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
| | - Bernhard Seiboth
- Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
| | - Christian P. Kubicek
- Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
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Bauer S, Vasu P, Persson S, Mort AJ, Somerville CR. Development and application of a suite of polysaccharide-degrading enzymes for analyzing plant cell walls. Proc Natl Acad Sci U S A 2006; 103:11417-22. [PMID: 16844780 PMCID: PMC1544100 DOI: 10.1073/pnas.0604632103] [Citation(s) in RCA: 230] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
To facilitate analysis of plant cell wall polysaccharide structure and composition, we cloned 74 genes encoding polysaccharide-degrading enzymes from Aspergillus nidulans, Aspergillus fumigatus, and Neurospora crassa and expressed the genes as secreted proteins with C-terminal Myc and 6x His tags. Most of the recombinant enzymes were active in enzyme assays, and optima for pH and temperature were established. A subset of the enzymes was used to fragment polysaccharides from the irregular xylem 9 (irx9) mutant of Arabidopsis. The analysis revealed a decrease in the abundance of xylan in the mutant, indicating that the IRX9 gene, which encodes a putative family 43 glycosyltransferase, is required for xylan synthesis.
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Affiliation(s)
| | - Prasanna Vasu
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078
| | | | - Andrew J. Mort
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078
| | - Chris R. Somerville
- *Carnegie Institution, Stanford, CA 94305; and
- To whom correspondence should be addressed. E-mail:
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Panagiotou G, Topakas E, Economou L, Kekos D, Macris BJ, Christakopoulos P. Induction, purification, and characterization of two extracellular α-L-arabinofuranosidases from Fusarium oxysporum. Can J Microbiol 2003; 49:639-44. [PMID: 14663498 DOI: 10.1139/w03-077] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the presence of L-arabinose as sole carbon source, Fusarium oxysporum produces two α-L-arabinofuranosidases (ABFs) named ABF1 and ABF2, with molecular masses of 200 and 180 kDa, respectively. The two F. oxysporum proteins have been purified to homogeneity. The purified enzymes are composed of three equal subunits and are neutral proteins with pIs of 6.0 and 7.3 for ABF1 and ABF2, respectively. With p-nitrophenyl α-L-arabinofuranoside (pNPA) as the substrate, ABF1 and ABF2 exhibited Km values of 0.39 and 0.28 mmol·L–1, respectively, and Vmax values of 1.6 and 4.6 µmol·min–1·(mg of protein)–1, respectively, and displayed optimal activity at pH 6.0 and 50–60 °C. ABFs released arabinose only from sugar beet arabinan and not from wheat soluble and insoluble arabinoxylans. The enzymes were not active on substrates containing ferulic acid ester linked to C-5 and C-2 linkages of pNPA showing that phenolic substituents of pNPA sterically hindered the action of ABFs.Key words: α-L-arabinofuranosidase, enzyme purification, enzyme induction.
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Affiliation(s)
- Gianni Panagiotou
- Chemical Engineering Department, National Technical University of Athens, Greece
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Takao M, Akiyama K, Sakai T. Purification and characterization of thermostable endo-1,5-alpha-L-arabinase from a strain of Bacillus thermodenitrificans. Appl Environ Microbiol 2002; 68:1639-46. [PMID: 11916679 PMCID: PMC123856 DOI: 10.1128/aem.68.4.1639-1646.2002] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A strain of a thermophilic bacterium, tentatively designated Bacillus thermodenitrificans TS-3, with arabinan-degrading activity was isolated. It produced an endo-arabinase (ABN) (EC 3.2.1.99) and two arabinofuranosidases (EC 3.2.1.55) extracellularly when grown at 60 degrees C on a medium containing sugar beet arabinan. The ABN (tentatively called an ABN-TS) was purified 7,417-fold by anion-exchange, hydrophobic, size exclusion, and hydroxyapatite chromatographies. The molecular mass of ABN-TS was 35 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the isoelectric point was pH 4.5. The enzyme was observed to be more thermostable than known ABNs; it had a half-life of 4 h at 75 degrees C. The enzyme had optimal activity at 70 degrees C and pH 6.0. The enzyme had apparent K(m) values of 8.5 and 45 mg/ml and apparent V(max) values of 1.6 and 1.1 mmol/min/mg of protein against debranched arabinan (alpha-1,5-arabinan) and arabinan, respectively. The enzyme had no pectin-releasing activity (protopectinase activity) from sugar beet protopectin, differing from an ABN (protopectinase-C) from mesophilic Bacillus subtilis IFO 3134. The pattern of degradation of debranched arabinan by ABN-TS indicated that the enzyme was an endo-acting enzyme and the main end products were arabinobiose and arabinose. The results of preliminary experiments indicated that the culture filtrate of strain TS-3 is suitable for L-arabinose production from sugar beet pulp at high temperature.
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Affiliation(s)
- Makoto Takao
- Department of Food and Nutrition, Faculty of Agriculture, Kinki University, 3327-204 Naka-machi, Nara 631-8505, Japan
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de Vries RP, Visser J. Aspergillus enzymes involved in degradation of plant cell wall polysaccharides. Microbiol Mol Biol Rev 2001; 65:497-522, table of contents. [PMID: 11729262 PMCID: PMC99039 DOI: 10.1128/mmbr.65.4.497-522.2001] [Citation(s) in RCA: 542] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Degradation of plant cell wall polysaccharides is of major importance in the food and feed, beverage, textile, and paper and pulp industries, as well as in several other industrial production processes. Enzymatic degradation of these polymers has received attention for many years and is becoming a more and more attractive alternative to chemical and mechanical processes. Over the past 15 years, much progress has been made in elucidating the structural characteristics of these polysaccharides and in characterizing the enzymes involved in their degradation and the genes of biotechnologically relevant microorganisms encoding these enzymes. The members of the fungal genus Aspergillus are commonly used for the production of polysaccharide-degrading enzymes. This genus produces a wide spectrum of cell wall-degrading enzymes, allowing not only complete degradation of the polysaccharides but also tailored modifications by using specific enzymes purified from these fungi. This review summarizes our current knowledge of the cell wall polysaccharide-degrading enzymes from aspergilli and the genes by which they are encoded.
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Affiliation(s)
- R P de Vries
- Molecular Genetics of Industrial Microorganisms, Wageningen University, 6703 HA Wageningen, The Netherlands.
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Abstract
Interest in the alpha-L-arabinofuranosidases has increased in recent years because of their application in the conversion of various hemicellulosic substrates to fermentable sugars for subsequent production of fuel alcohol. Xylanases, in conjunction with alpha-L-arabinofuranosidases and other accessory enzymes, act synergistically to degrade xylan to component sugars. The induction of alpha-L-arabinofuranosidase production, physico-chemical characteristics, substrate specificity, and molecular biology of the enzyme are described. The current state of research and development of the arabinofuranosidases and their role in biotechnology are presented.
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Affiliation(s)
- B C Saha
- Fermentation Biochemistry Research Unit, National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Agricultural Research Service, Peoria, IL 61604, USA.
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Kaneko S, Arimoto M, Ohba M, Kobayashi H, Ishii T, Kusakabe I. Purification and substrate specificities of two alpha-L-arabinofuranosidases from Aspergillus awamori IFO 4033. Appl Environ Microbiol 1998; 64:4021-7. [PMID: 9758835 PMCID: PMC106594 DOI: 10.1128/aem.64.10.4021-4027.1998] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
alpha-L-Arabinofuranosidases I and II were purified from the culture filtrate of Aspergillus awamori IFO 4033 and had molecular weights of 81,000 and 62,000 and pIs of 3.3 and 3.6, respectively. Both enzymes had an optimum pH of 4.0 and an optimum temperature of 60 degreesC and exhibited stability at pH values from 3 to 7 and at temperatures up to 60 degrees C. The enzymes released arabinose from p-nitrophenyl-alpha-L-arabinofuranoside, O-alpha-L-arabinofuranosyl-(1-->3)-O-beta-D-xylopyranosyl-(1-->4)-D-x ylopyranose, and arabinose-containing polysaccharides but not from O-beta-D-xylopyranosyl-(1-->2)-O-alpha-L-arabinofuranosyl-(1-->3)-O-b eta-D-xylopyranosyl-(1-->4)-O-beta-D-xylopyranosyl-(1-->4)-D-xylopyra nose. alpha-L-Arabinofuranosidase I also released arabinose from O-beta-D-xylopy-ranosyl-(1-->4)-[O-alpha-L-arabinofuranosyl- (1-->3)]- O-beta-D-xylopyranosyl-(1-->4)-D-xylopyranose. However, alpha-L-arabinofuranosidase II did not readily catalyze this hydrolysis reaction. alpha-L-Arabinofuranosidase I hydrolyzed all linkages that can occur between two alpha-L-arabinofuranosyl residues in the following order: (1-->5) linkage > (1-->3) linkage > (1-->2) linkage. alpha-L-Arabinofuranosidase II hydrolyzed the linkages in the following order: (1-->5) linkage > (1-->2) linkage > (1-->3) linkage. alpha-L-Arabinofuranosidase I preferentially hydrolyzed the (1-->5) linkage of branched arabinotrisaccharide. On the other hand, alpha-L-arabinofuranosidase II preferentially hydrolyzed the (1-->3) linkage in the same substrate. alpha-L-Arabinofuranosidase I released arabinose from the nonreducing terminus of arabinan, whereas alpha-L-arabinofuranosidase II preferentially hydrolyzed the arabinosyl side chain linkage of arabinan.
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Affiliation(s)
- S Kaneko
- Institute of Applied Biochemistry, University of Tsukuba, 1-1-1 Tennoodai, Tsukuba, Ibaraki 305, Japan
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Saha BC, Bothast RJ. Purification and characterization of a novel thermostable alpha-L-arabinofuranosidase from a color-variant strain of Aureobasidium pullulans. Appl Environ Microbiol 1998; 64:216-20. [PMID: 9435077 PMCID: PMC124696 DOI: 10.1128/aem.64.1.216-220.1998] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/1997] [Accepted: 10/29/1997] [Indexed: 02/05/2023] Open
Abstract
A color-variant strain of Aureobasidium pullulans (NRRL Y-12974) produced alpha-L-arabinofuranosidase (alpha-L-AFase) when grown in liquid culture on oat spelt xylan. An extracellular alpha-L-AFase was purified 215-fold to homogeneity from the culture supernatant by ammonium sulfate treatment, DEAE Bio-Gel A agarose column chromatography, gel filtration on a Bio-Gel A-0.5m column, arabinan-Sepharose 6B affinity chromatography, and SP-Sephadex C-50 column chromatography. The purified enzyme had a native molecular weight of 210,000 and was composed of two equal subunits. It had a half-life of 8 h at 75 degrees C, displayed optimal activity at 75 degrees C and pH 4.0 to 4.5, and had a specific activity of 21.48 mumol min-1. mg-1 of protein against p-nitrophenyl-alpha-L-arabinofuranoside (pNP alpha AF). The purified alpha-L-AFase readily hydrolyzed arabinan and debranched arabinan and released arabinose from arabinoxylans but was inactive against arabinogalactan. The K(m) values of the enzyme for the hydrolysis of pNP alpha AF, arabinan, and debranched arabinan at 75 degrees C and pH 4.5 were 0.26 mM, 2.14 mg/ml, and 3.25 mg/ml, respectively. The alpha-L-AFase activity was not inhibited at all by L-arabinose (1.2 M). The enzyme did not require a metal ion for activity, and its activity was not affected by p-chloromercuribenzoate (0.2 mM), EDTA (10 mM), or dithiothreitol (10 mM).
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Affiliation(s)
- B C Saha
- Fermentation Biochemistry Research Unit, National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Peoria, Illinois 61604, USA.
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Sánchez-Torres P, González-Candelas L, Ramón D. Expression in a wine yeast strain of the Aspergillus niger abfB gene. FEMS Microbiol Lett 1996; 145:189-94. [PMID: 8961556 DOI: 10.1111/j.1574-6968.1996.tb08576.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A recombinant wine yeast strain has been constructed expressing the gene coding for alpha-L-arabinofuranosidase B from Aspergillus niger under the control of the yeast actin gene promoter. The protein is efficiently secreted by the recombinant yeast, allowing its purification and characterisation. The heterologous alpha-L-arabinofuranosidase B shows similar physico-chemical properties to the native enzyme. The wine produced in microvinification experiments using the recombinant yeast presents the same oenological characteristics as obtained with the untransformed strain. The alpha-L-arabinofuranosidase B protein is detected throughout the fermentation.
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Affiliation(s)
- P Sánchez-Torres
- Departamento de Biotecnología de Alimentos, Consejo Superior de Investigaciones Científicas, Valencia, Spain
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van der Veen P, Arst HN, Flipphi MJ, Visser J. Extracellular arabinases in Aspergillus nidulans: the effect of different cre mutations on enzyme levels. Arch Microbiol 1994; 162:433-40. [PMID: 7872840 DOI: 10.1007/bf00282109] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The regulation of the syntheses of two arabinan-degrading extracellular enzymes and several intracellular L-arabinose catabolic enzymes was examined in wild-type and carbon catabolite derepressed mutants of Aspergillus nidulans. alpha-L-Arabinofuranosidase B, endoarabinase, L-arabinose reductase, L-arabitol dehydrogenase, xylitol dehydrogenase, and L-xylulose reductase were all inducible to varying degrees by L-arabinose and L-arabitol and subject to carbon catabolite repression by D-glucose. With the exception of L-xylulose reductase, all were clearly under the control of creA, a negative-acting wide domain regulatory gene mediating carbon catabolite repression. Measurements of intracellular enzyme activities and of intracellular concentrations of arabitol and xylitol in mycelia grown on D-glucose in the presence of inducer indicated that carbon catabolite repression diminishes, but does not prevent uptake of inducer. Mutations in creA resulted in an apparently, in some instances very marked, elevated inducibility, perhaps reflecting an element of "self" catabolite repression by the inducing substrate. creA mutations also resulted in carbon catabolite derepression to varying degrees. The regulatory effects of a mutation in creB and in creC, two genes whose roles are unclear, but likely to be indirect, were, when observable, more modest. As with previous data showing the effect of creA mutations on structural gene expression, there were striking instances of phenotypic variation amongst creA mutant alleles and this variation followed no discernible pattern, i.e. it was non-hierarchical. This further supports molecular data obtained elsewhere, indicating a direct role for creA in regulating structural gene expression, and extends the range of activities under creA control.
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Affiliation(s)
- P van der Veen
- Section Molecular Genetics of Industrial Microorganisms, Wageningen Agricultural University, The Netherlands
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de Vries RP, Flipphi MJ, Witteveen CF, Visser J. Characterization of an Aspergillus nidulans L-arabitol dehydrogenase mutant. FEMS Microbiol Lett 1994; 123:83-90. [PMID: 7988903 DOI: 10.1111/j.1574-6968.1994.tb07205.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The degradation pathway for L-arabinose, which consists of a sequence of alternating reduction and oxidation reactions prior to ultimate phosphorylation, was studied in Aspergillus nidulans wild-type as well as in an L-arabinose non-utilizing mutant. The inability of the mutant to use L-arabinose was caused by the absence of L-arabitol dehydrogenase activity. The effect of the mutation on polyol accumulation patterns was studied upon growth on various carbon sources. The presence of L-arabinose resulted in intracellular accumulation of arabitol in this mutant. Moreover, the mutant secreted arabitol under these conditions and, in contrast to the wild-type, featured enhanced expression of enzymes involved in L-arabinose catabolism as well as of extracellular glycosyl hydrolases involved in degradation of the plant cell wall polysaccharide L-arabinan.
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Affiliation(s)
- R P de Vries
- Section Molecular Genetics of Industrial Microorganisms, Wageningen Agricultural University, The Netherlands
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Kester HC, Visser J. Purification and characterization of pectin lyase B, a novel pectinolytic enzyme fromAspergillus niger. FEMS Microbiol Lett 1994. [DOI: 10.1111/j.1574-6968.1994.tb07008.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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