Bioscience, Biotechnology, and Biochemistry
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68 巻 , 7 号
選択された号の論文の34件中1~34を表示しています
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Analytical Chemistry Regular Paper
  • Tadayuki TSUKATANI, Seiji IDE, Hiroyuki UKEDA, Kiyoshi MATSUMOTO
    68 巻 (2004) 7 号 p. 1525-1532
    公開日: 2004/07/23
    ジャーナル フリー
    The metabolic efficiency of seven derivatives of 1,4-benzoquinone (BQ) by yeast cells and the oxidative characteristics of the corresponding hydroquinones (HQs) were studied by electrochemical, spectrophotometric and chemiluminescent methods. The spectrophotometric method was based on the reduction of a tetrazolium salt to formazan dye during the autoxidation of HQs generated by yeast cells under alkaline conditions. The amounts of HQs detected directly by the electrochemical method did not agree with those calculated from the formazan dye obtained by the spectrophotometric method. A tetrazolium salt was reduced to a formazan dye by both the superoxide anion radical (O2•) generated during the autoxidation of 2,3,5,6-tetramethyl-1,4-HQ and by HQ itself. Little formazan dye was formed, and hydrogen peroxide (H2O2) was then finally produced during the autoxidation of 1,4-HQ or 2-methyl-1,4-HQ. Formazan dye and H2O2 were generated at a certain ratio during the autoxidation of derivatives of dimethyl-1,4-HQ or 2,3,5-trimethyl-1,4-HQ. The analytical method based on chemiluminescence with lucigenin and 2,3,5,6-tetramethyl-1,4-BQ was applied to highly sensitive measurement of the yeast cell density. A linear relationship between the chemiluminescence intensity and viable cell density was obtained in the range of 1.2×103–4.8×104 cells/ml. The detection limit was 4.8×102 cells/ml.
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Organic Chemistry Regular Papers
  • Suthasinee PITCHAYAWASIN, Minoru ISOBE
    68 巻 (2004) 7 号 p. 1424-1433
    公開日: 2004/07/23
    ジャーナル フリー
    We established a method to determine the glycosyl linkage structure by a combination of Smith degradation and liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-Q-TOF-MS) and tandem MS (MS/MS). To assign the sugar linkage of N-glycoprotein, we employed a typical ribonuclease B containing oligosaccharides (Man5–9GlcNAc2). Tryptic digestion of ribonuclease B provided a mixture of high-mannose glycopeptides consisting of the four amino acids, Asn34-Leu-Thr-Lys37 (NLTK, T6). The mixture of glycopeptides was separated by high-performance liquid chromatography (HPLC) in a reversed phase column and was characterized by ESI-Q-TOF-MS and MS/MS. Comparison of the data with and without Smith degradation allowed us to make reasonable assignments to support such linkage patterns as (1→2), (1→3), (1→6) and their multiples. These assignments were limited to six mannoses or lower due to the unstable nature of the higher derivatives. This method should be applicable to determine the linkage pattern of an unknown glycoprotein in about a 6-microgram amount.
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  • Yusuke JIKUMARU, Tadao ASAMI, Hideharu SETO, Shigeo YOSHIDA, Tadashi Y ...
    68 巻 (2004) 7 号 p. 1461-1466
    公開日: 2004/07/23
    ジャーナル フリー
    Several types of jasomonic acid (JA) derivatives, including JA–amino acid conjugates, a JA–biotin conjugate, a JA–dexamethasone heterodimer, and a JA–fluoresceine conjugate, were prepared as candidates for molecular probes to identify JA-binding proteins. These JA derivatives, excepting the JA–fluoresceine conjugate, exhibited significant biological activities in a rice seedling assay, a rice phytoalexin-inducing assay, and/or a soybean phenylalanine ammonia-lyase-inducing assay. These JA derivatives could therefore be useful probes for identifying JA-binding proteins. The activity spectra of the prepared compounds were different from each other, suggesting that different types of JA receptors were involved in the perception of JA derivatives in the respective bioassays.
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Organic Chemistry Notes
Organic Chemistry Communication
Biochemistry & Molecular Biology Regular Papers
  • Zhuanhua WANG, Zheng ZHANG, Zhuohui ZHAO, Gunilla WIESLANDER, Dan NORB ...
    68 巻 (2004) 7 号 p. 1409-1413
    公開日: 2004/07/23
    ジャーナル フリー
    A 24 kDa protein was isolated from tartary buckwheat seeds by using chromatography of Superdex 75 gel filtration and Resource Q ion-exchange column. SDS-PAGE and Sephacryl S-200 gel filtration were used to provide information about the molecular mass of the protein purified from tartary buckwheat. The protein was composed of 215 amino acid residues and showed strong IgE binding activity in an ELISA test to the sera colleted from two patients allergic to buckwheat. These results suggested that the purified 24 kDa protein from tartary buckwheat seeds was an important functional protein and was relatively specific for buckwheat-allergic patients. It should be a very useful tool in the diagnosis of buckwheat allergy in the future.
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  • Il-Dong CHOI, Gyong-Sik HA, Kyung-Nam KIM, Yong-Jin CHOI
    68 巻 (2004) 7 号 p. 1414-1423
    公開日: 2004/07/23
    ジャーナル フリー
    The gene encoding the catabolite control protein A (CcpA) of Bacillus stearothermophilus No. 236, a strong xylanolytic bacterium, was cloned, sequenced, and expressed in Escherichia coli. The nucleotide sequence of the ccpA gene corresponded to an open reading frame of 1,005 bp that encodes a polypeptide of 334 amino acid residues with a calculated molecular mass of 36,902 kDa. The CcpA protein belonging to the LacI/GalR family of transcriptional regulators was produced by a recombinant E. coli strain expressing the B. stearothermophilus No. 236 ccpA gene and purified to apparent homogeneity. The transcription start site was mapped at a position 63 nucleotides upstream of the translation initiation codon, and a presumed promoter sequence was also identified. The deduced amino acid sequence of the ccpA gene product contained the helix-turn-helix motif found in many DNA-binding proteins, and showed the highest identity (62%) with CcpA from B. subtilis. The B. stearothermophilus No. 236 ccpA gene was demonstrated to be able to complement a B. subtilis ccpA mutant that exhibited two distinct mutant phenotypes: a growth defect and a release of carbon catabolite repression (CCR). These results indicate that the ccpA gene product of B. stearothermophilus No. 236 is functionally active also in B. subtilis. Electrophoretic mobility shift assay with the purified CcpA revealed that the CcpA of B. stearothermophilus No. 236 bound specifically to the xynA creB (catabolite responsive element B) sequence. Taken together, these results strongly suggest that the CcpA protein participates in CCR of B. stearothermophilus No. 236 xynA gene.
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  • Kiyofumi MARUYAMA, Tomohiko SHIBAYAMA, Aki ICHIKAWA, Yukari SAKOU, Sat ...
    68 巻 (2004) 7 号 p. 1434-1441
    公開日: 2004/07/23
    ジャーナル フリー
    The 2-pyrone-4,6-dicarboxylate lactonase gene (proL), the protocatechuate 4,5-dioxygenase α and β subunits genes (proOa and proOb), and the 4-carboxy-2-hydroxymuconate-6-semialdehyde dehydrogenase gene (proD) were cloned from the chromosomal DNA of Pseudomonas ochraceae NGJ1. These genes were in the order proLOaObD on the DNA, and a possible transcription terminator sequence followed. The proL and proD genes were over-expressed in Escherichia coli, and their gene products were purified for identification, while the expression of proOaOb was at a lower level. The protocatechuate meta-degradation operon was reconstituted with the recombinant plasmids and expressed successfully in E. coli.
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  • Yoshiya GUNJI, Nobuharu TSUJIMOTO, Megumi SHIMAOKA, Yuri OGAWA-MIYATA, ...
    68 巻 (2004) 7 号 p. 1449-1460
    公開日: 2004/07/23
    ジャーナル フリー
    The L-lysine biosynthetic pathway of the gram-negative obligate methylotroph Methylophilus methylotrophus AS1 was examined through characterization of the enzymes aspartokinase (AK), aspartsemialdehyde dehydrogenase, dihydrodipicolinate synthase (DDPS), dihydrodipicolinate reductase, and diaminopimelate decarboxylase. The AK was inhibited by L-threonine and by a combination of L-threonine and L-lysine, but not by L-lysine alone, and the activity of DDPS was moderately reduced by L-lysine. In an L-lysine producing mutant (G49), isolated as an S-(2-aminoethyl)-L-cysteine (lysine analog) resistant strain, both AK and DDPS were partially resistant to feedback inhibition. The ask and dapA genes encoding AK and DDPS respectively were isolated from the parental strain, AS1, and its G49 derivative. Comparison of the sequences revealed a point mutation in each of these genes in G49. The mutation in the ask gene altered aspartic acid in a key region involved in the allosteric regulation common to AKs, while a novel mutation in the dapA gene altered tyrosine-106, which was assumed to be involved in the binding of L-lysine to DDPS.
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  • Yasuhiro MATSUO, Katsunori TANAKA, Tsuyoshi NAKAGAWA, Hideyuki MATSUDA ...
    68 巻 (2004) 7 号 p. 1489-1499
    公開日: 2004/07/23
    ジャーナル フリー
    To explore the function of chitin in Schizosaccharomyces pombe, we have cloned chs1+ and chs2+, encoding putative chitin synthases, based on sequences in the Sanger Centre database. The synthetic lethal phenotype of the S. cerevisiae chs1 chs2 chs3 mutant was complemented by expression of S. pombe chs1+ or chs2+, indicating that both chs1+ and chs2+ in fact encode chitin synthase. The homothallic Δchs1 strain formed abnormal asci that contained 1, 2, or 3 spores, while the Δchs2 strain had no noticeable phenotype. The chs1 chs2 double disruptant looked similar phenotypically to the Δchs1 strain. The Chs2-GFP fusion protein predominantly localized at the septum after the septum was formed during vegetative growth. The level of chs2+ mRNA increased just before the septum was formed. Levels of Chs2-13Myc synthesis also changed during the cell cycle. Thus, chs1+ is required for proper spore formation, and chs2+ is perhaps involved in septum formation.
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  • Takuji MITSUNAGA, Minoru IWASE, Wimal UBHAYASEKERA, Sherry L. MOWBRAY, ...
    68 巻 (2004) 7 号 p. 1508-1517
    公開日: 2004/07/23
    ジャーナル フリー
    Genomic DNA for a class IV chitinase was cloned from yam (Dioscorea opposita Thunb) leaves and sequenced. The deduced amino acid sequence shows 50 to 59% identity to class IV chitinases from other plants. The yam chitinase, however, has an additional sequence of 8 amino acids (a C-terminal extension) following the cysteine that was reported as the last amino acid for other class IV chitinases; this extension is perhaps involved in subcellular localization. A homology model based on the structure of a class II chitinase from barley was used as an aid to interpreting the available data. The analysis suggests that the class IV enzyme recognizes an even shorter segment of the substrate than class I or II enzymes. This observation might help to explain why class IV enzymes are better suited to attack against pathogen cell walls.
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  • Takuji MITSUNAGA, Minoru IWASE, Dai YUKI, Daizo KOGA
    68 巻 (2004) 7 号 p. 1518-1524
    公開日: 2004/07/23
    ジャーナル フリー
    Genomic DNA encoding a class IV chitinase was cloned from yam (Dioscorea opposita Thunb) leaves in previous research (Biosci. Biotechnol. Biochem., 68, 1508–1517 (2004)). But this chitinase had an additional sequence composed of eight amino acids (a C-terminal extension) at the C-terminal, compared with class IV chitianses from other plants. In order to clarify the role of this C-terminal extension in cellular localization, plants and suspension-cultured cells of Nicotiana tabacum were transformed with either the cloned yam class IV chitinase gene carrying the C-terminal extension or its truncated gene by the Agrobacterium-mediated method, and then their localization was investigated. The results suggest that the C-terminal extension of yam class IV chitinase plays a role as a targeting signal for plant vacuoles. This is the first report presenting the existence of vacuolar type class IV chitinase.
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  • Mihwan KIM, Yoshitaka NISHIYAMA, Kiyoshi MURA, Chiyoko TOKUE, Soichi A ...
    68 巻 (2004) 7 号 p. 1533-1540
    公開日: 2004/07/23
    ジャーナル フリー
    A Bacillus vietnamensis metalloprotease (BVMP) with high affinity toward collagen was isolated and purified from the culture supernatant of Bacillus vietnamensis 11-4 occurring in Vietnamese fish sauces. The BVMP gene was cloned and its nucleotide and coded amino acid sequences determined. BVMP consists of 547 amino acid residues, with the zinc-binding sites conserved in common metalloproteases. It shares 57% amino acid identity with thermolysin originating from Bacillus thermoproteolyticus. The three-dimensional structure of BVMP was deduced by computer-aided modeling with the use of the known three-dimensional thermolysin structure as a template. Like thermolysin, BVMP cleaved the oxidized insulin B-chain at the peptide bonds involving the N-terminal sides of hydrophobic and aromatic amino acids. BVMP also showed high hydrolytic activity toward gelatin, collagen, casein, and elastin, especially toward the skeletal proteins at increased NaCl concentration. The high activity was found to be due to enhanced affinity to the substrates. Kinetical data on BVMP indicated that the Km values for the hydrolysis of Cbz-GPGGPA as a collagen model decreased as the concentration of added NaCl increased. Some contribution of this enzyme during the aging of fish sauces at high salt concentrations can thus be expected.
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  • Hiroshi OKAZAKI, Bun-ichiro ONO, Yoshinori OHSUMI, Mariko OHSUMI
    68 巻 (2004) 7 号 p. 1541-1548
    公開日: 2004/07/23
    ジャーナル フリー
    Autophagy is a complex cellular process by which starving cells utilize cytoplasmic macromolecules as nutritional resources. In Saccharomyces cerevisiae, more than 15 genes are involved in this process and most of them have been cloned and characterized by now. But there remains a complementation group represented by a single mutation, apg15-1, unclear as to its molecular nature. We obtained DNA fragments that functionally complemented apg15-1 and found that the responsible ORF, YMR159C, was already assigned as APG16. It was further found that apg15-1 was a UGA allele in which the 243rd base of the 450 bp coding region of APG16 was converted from C to T, and that the previously observed complementation between apg15-1 and apg16D was attributable to the action of a cytoplasmic omnipotent suppressor. This suppressor was readily cured by guanidine-HCl and also by overexpression or disruption of HSP104, indicating its close similarity to the PSI prion-like factor. Since apg15-1 is a mutation highly sensitive to termination suppression, it can be used as a tool to detect weak termination suppressors.
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  • Wenhui WU, Ritsuko NARASAKI, Fumihiko MAEDA, Keiji HASUMI
    68 巻 (2004) 7 号 p. 1549-1556
    公開日: 2004/07/23
    ジャーナル フリー
    Reciprocal activation of prourokinase (pro-u-PA) and plasminogen is an important mechanism in the initiation and propagation of local fibrinolytic activity. We found that glucosyldiacylglycerol (GDG) enhanced the reciprocal activation by 1.5- to 2-fold at 0.7–16 μM, accompanying increased conversions of both zymogens to active two-chain forms. The reciprocal activation system consists of (i) plasminogen activation by pro-u-PA to form plasmin, (ii) pro-u-PA activation by the resulting plasmin to form two-chain u-PA (tcu-PA), and (iii) plasminogen activation by the resulting tcu-PA. Whereas GDG minimally affected steps (ii) and (iii) in isolated systems, it markedly enhanced step (i) in the absence of the conversion of pro-u-PA to tcu-PA. GDG significantly increased the intrinsic fluorescence of pro-u-PA (6.7%), but not that of tcu-PA or plasminogen. The large change in intrinsic fluorescence suggests that GDG selectively affects pro-u-PA to alter its conformation, and this mechanism may account for enhancement of its intrinsic plasminogen activator activity.
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Biochemistry & Molecular Biology Notes
Biochemistry & Molecular Biology Communications
  • Akira HAMADA, Ken-ichi YAMAGUCHI, Michiko HARADA, Seiya NIKUMARU, Jun ...
    68 巻 (2004) 7 号 p. 1611-1616
    公開日: 2004/07/23
    ジャーナル フリー
    The acid phosphatase gene from lupin was expressed in transgenic rice plants under the control of the maize ubiquitin promoter or rice chlorophyll a/b binding protein (Cab) promoter. Transgenic rice leaves exhibited up to an 18-fold increase in phytate-hydrolyzing activity. Based on the phytate-hydrolyzing activity at pH 5.5, more than 85% this activity was retained after heat-treatment at 80 °C for 15 min, and the heterologous enzyme in leaf sections and leaf extracts was relatively stable during storage. A distinct increase in released phosphate was observed when the heterologous enzyme was mixed with the feed extract. These results suggest that the heterologous enzyme in rice plants may maintain its desired characteristics as a phytate-hydrolyzing enzyme when added to animal feed.
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  • Hee Tae JEONG, Yasuo OOWATARI, Michiyo ABE, Katsunori TANAKA, Hideyuki ...
    68 巻 (2004) 7 号 p. 1621-1626
    公開日: 2004/07/23
    ジャーナル フリー
    The sexual differentiation of Schizosaccharomyces pombe is controlled by many cellular components which have not been fully characterized. We isolated a gene called msa2 as a multi-copy suppressor of a sporulation abnormal mutant (sam1). Msa2p is identical with Nrd1p which has been characterized as a factor that blocks the onset of sexual differentiation. The yeast two-hybrid system was used to identify Cpc2p, a fission yeast homolog of the RACK1 protein, that interacted with Msa2p/Nrd1p. We confirmed that Msa2p/Nrd1p interacted with Cpc2p in S. pombe cells. An epistatic analysis of msa2/nrd1 and cpc2 suggests that Msa2p/Nrd1p was an upstream regulator for Cpc2p. A localization analysis of Cpc2p and Msa2p/Nrd1p indicates that both proteins were predominantly localized in the cytoplasm. The interaction of negative regulator Msa2p/Nrd1p with positive regulator Cpc2p suggests a new regulatory circuit in the sexual differentiation of S. pombe.
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Food & Nutrition Science Regular Paper
  • Katsuhisa HARADA, Mitsuyoshi KANO, Tomomi TAKAYANAGI, Osamu YAMAKAWA, ...
    68 巻 (2004) 7 号 p. 1500-1507
    公開日: 2004/07/23
    ジャーナル フリー
    We evaluated the absorbability of anthocyanins in humans and rats administered with a beverage prepared from an extract of the tuber of purple sweet potato (Ipomoea batatas Cultivar Ayamurasaki), or with an anthocyanin concentrate. Two major anthocyanin components, cyanidin 3-O-(2-O-(6-O-(E)-caffeoyl-β-D-glucopyranosyl)-β-D-glucopyranoside)-5-O-β-D-glucopyranoside) and peonidin 3-O-(2-O-(6-O-(E)-caffeoyl-β-D-glucopyranosyl)-β-D-glucopyranoside)-5-O-β-D-glucopyranoside), were detected in the plasma and urine of both rats and humans by HPLC or liquid chromatography/mass spectrometry (LC/MS). The plasma concentration of anthocyanins in humans reached a maximum 90 minutes after ingestion, and the recovery of anthocyanins in the urine was estimated as 0.01–0.03%. These results indicate that acylated anthocyanins could be selectively absorbed after ingesting food.
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Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Osamu NISHIDA, Seigo KUWAZAKI, Chise SUZUKI, Jun SHIMA
    68 巻 (2004) 7 号 p. 1442-1448
    公開日: 2004/07/23
    ジャーナル フリー
    Yeast strains were isolated from dried sweet potatoes (hoshi-imo), a traditional preserved food in Japan. Dough fermentation ability, freeze tolerance, and growth rates in molasses, which are important characteristics of commercial baker’s yeast, were compared between these yeast strains and a commercial yeast derivative that had typical characteristics of commercial strains. Classification tests including pulse-field gel electrophoresis and fermentation/assimilation ability of sugars showed that almost the stains isolated belonged to Saccharomyces cerevisiae. One strain, ONY1, accumulated intracellular trehalose at a higher level than commercial strain T128. Correlated with intracellular trehalose contents, the fermentation ability of high-sugar dough containing ONY1 was higher. ONY1 also showed higher freeze tolerance in both low-sugar and high-sugar doughs. The growth rate of ONY1 was significantly higher under batch and fed-batch cultivation conditions using either molasses or synthetic medium than that of strain T128. These results suggest that ONY1 has potential commercial use as baker’s yeast for frozen dough and high-sugar dough.
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  • Kengo INOUE, Jaka WIDADA, Seiichiro NAKAI, Takayuki ENDOH, Masaaki URA ...
    68 巻 (2004) 7 号 p. 1467-1480
    公開日: 2004/07/23
    ジャーナル フリー
    Southern hybridization analysis of the genomes from the newly-isolated 10 carbazole (CAR)-utilizing bacteria revealed that 8 of the isolates carried gene clusters homologous to the CAR-catabolic car operon of Pseudomonas resinovorans strain CA10. Sequencing analysis showed that two car operons and the neighboring regions of Pseudomonas sp. strain K23 are nearly identical to that of strain CA10. In contrast to strains CA10 and K23, carEF genes did not exist downstream of the car gene cluster of Janthinobacterium sp. strain J3. In the car gene clusters, strains CA10, K23 and J3 have Rieske-type ferredoxin as a component of carbazole dioxygenase, although Sphingomonas sp. strain KA1 possesses a putidaredoxin-type ferredoxin. We confirmed that this putidaredoxin-type ferredoxin CarAc can function as an electron mediator to CarAa of strain KA1. In the upstream regions of the carJ3 and carKA1 gene clusters, ORFs whose deduced amino acid sequences showed homology to GntR-family transcriptional regulators were identified.
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  • Masaru WADA, Ayumi YOSHIZUMI, Yuki FURUKAWA, Hiroshi KAWABATA, Makoto ...
    68 巻 (2004) 7 号 p. 1481-1488
    公開日: 2004/07/23
    ジャーナル フリー
    Exiguobacterium sp. F42 was screened as a producer of an enzyme catalyzing the NADPH-dependent stereoselective reduction of ethyl 3-oxo-3-(2-thienyl)propanoate (KEES) to ethyl (S)-3-hydroxy-3-(2-thienyl)propanoate ((S)-HEES). (S)-HEES is a key intermediate for the synthesis of (S)-duloxetine, a potent inhibitor of the serotonin and norepinephrine uptake carriers. The responsible enzyme (KEES reductase) was partially purified, and the gene encoding KEES reductase was cloned and sequenced via an inverse PCR approach. Sequence analysis of the gene for KEES reductase revealed that the enzyme was a member of the short chain dehydrogenase/reductase family. The probable NADPH-interacting site and 3 catalytic residues (Ser-Tyr-Lys) were fully conserved. The gene was highly expressed in Escherichia coli, and the gene product was purified to homogeneity from the recombinant E. coli by simpler procedures than from the original host. The molecular mass of the purified enzyme was 27,500 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and 55,000 as determined by gel filtration chromatography. Our results show that this enzyme can be used for the practical production of (S)-HEES.
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  • Hidenori TAGUCHI, Daisuke HAGIWARA, Tsutomu GENMA, Shuichi KARITA, Tet ...
    68 巻 (2004) 7 号 p. 1557-1564
    公開日: 2004/07/23
    ジャーナル フリー
    An EcoRI chromosomal DNA fragment of Ruminococcus albus F-40 that conferred endoglucanase activity on Escherichia coli was cloned. An open reading frame (ORF1) and another incomplete reading frame (ORF2) were found in the EcoRI fragment. The ORF2 was completed using inverse PCR genome walking technique. ORF1 and ORF2, which confront each other, encoded cellulases belonging to families 5 and 9 of the glycoside hydrolases and were designated cel5D and cel9A respectively. The cel5D gene encodes 753 amino acids with a deduced molecular weight of 83,409. Cel5D consists of a signal peptide of 24 amino acids, a family-5 catalytic module, a dockerin module, and two family-4 carbohydrate-binding modules (CBMs). The cel9A gene encodes 936 amino acids with a deduced molecular weight of 104,174, consisting of a signal peptide, a family-9 catalytic module, a family-3 CBM, and a dockerin module. The catalytic module polypeptide (rCel5DCat) derived from Cel5D was constructed, expressed, and purified from a recombinant E. coli. The truncated enzyme hydrolyzed cellohexaose, cellopentaose, and cellotetraose to yield mainly cellotriose and cellobiose with glucose as a minor product, but the enzyme was less active toward cellotriose and not active toward cellobiose, suggesting that this enzyme is a typical endoglucanase. rCel5DCat had a Km of 3.9 mg/ml and a Vmax of 37.2 μmol/min/mg for carboxymethycellulose.
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Microbiology & Fermentation Technology Notes
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