Bioscience, Biotechnology, and Biochemistry
Online ISSN : 1347-6947
Print ISSN : 0916-8451
Volume 73 , Issue 8
Showing 1-40 articles out of 40 articles from the selected issue
Analytical Chemistry Note
Organic Chemistry Regular Papers
Organic Chemistry Notes
Biochemistry & Molecular Biology Regular Papers
  • Yusuke SATO, Motoyuki SHIMIZU, Wataru MIZUNOYA, Hiroyuki WARIISHI, Ryu ...
    2009 Volume 73 Issue 8 Pages 1748-1756
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Denervation is known to induce skeletal muscle atrophy and fiber-type transitions, the molecular mechanisms of which are poorly understood. To investigate the effect of denervation on skeletal muscle, proteomic analysis was performed to compare denervated soleus muscle with normal soleus muscle. The muscles were fractionated to myofibrillar and sarcoplasmic fractions, which were analysed using two-dimensional gel electrophoresis (2-DE), followed by MALDI-TOF-MS. At least 30 differentially regulated proteins were identified in the sarcoplasmic fractions of normal and denervated soleus muscles. This group included metabolic enzymes, signaling molecules, chaperones, and contractile proteins. We also found two proteins, APOBEC-2 (RNA-editing enzyme) and Gamma-synuclein (breast cancer related protein), which have not been recognized as denervation-induced proteins to date. Our results might prove to be beneficial in elucidating the molecular mechanisms of denervation-induced muscle atrophy.
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  • Cui-Fang YE, He LI
    2009 Volume 73 Issue 8 Pages 1787-1792
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Diabetes frequently develops in Huntington’s disease patients. Here, we found that mutant huntingtin forms aggregates in the cytoplasm and reduces insulin secretion from huntingtin transfected pancreatic β cell lines, NIT-1 cells. Activity of the pro-survival factor, Akt, is enhanced in these cells, which might improve the maintenance of insulin content. Overexpression of heat shock protein 40 (HSP40) inhibits aggregation, reverses impaired insulin release, and blocks the enhancement of Akt activity. These results suggest that impairment of β cells is mostly linked with the aggregate formation of mutant huntingtin, and that HSP40 ameliorates the malfunction of pancreatic β cells by inhibiting aggregation.
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  • Tatsuki SUGIURA, Kenji YAMAGISHI, Toshiyuki KIMURA, Tomoaki NISHIDA, H ...
    2009 Volume 73 Issue 8 Pages 1793-1798
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Two genes, encoding YK-LiP1 and YK-LiP2, were cloned from the white-rot fungus Phanerochaete sordida YK-624, and a homologous expression system for the gene was constructed. Two full-length cDNAs (ylpA and ylpB) were isolated by degenerate RT-PCR and RACE-PCR. The results of N-terminal amino acid sequence analysis of native YK-LiP1 and YK-LiP2 showed that ylpA and ylpB coded for YK-LiP2 and YK-LiP1 respectively. The promoter of glyceraldehyde-3-phosphate dehydrogenase cloned from P. sordida YK-624 (PsGPD) was used to drive the expression of ylpA. Expression vector pGPD-g-ylpA was transformed into a P. sordida YK-624 uracil auxotrophic mutant, UV-64. The YlpA protein was secreted in active form by the transformants after 4 d of growth in a medium containing an excessive nitrogen source, whereas endogenous YK-LiP1 and YK-LiP2 were not produced. The physical and catalytic properties of the purified YlpA protein were very similar to those of YK-LiP2. These results suggest that homologous expression of recombinant YK-LiP2 was successful.
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  • Yuki KAWAKAMI, Noriyuki KUBOTA, Natsuki EKUNI, Toshiko SUZUKI-YAMAMOTO ...
    2009 Volume 73 Issue 8 Pages 1811-1817
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    8S-Lipoxygenase (8S-LOX) is known as a mouse homolog of human 15S-LOX-2. 15S-LOX-2 was down-regulated in malignant transformation of prostate epithelial cells, and its overexpression caused cell cycle arrest. To determine whether 8S-LOX would have a growth inhibitory effect on prostate carcinoma, we obtained human prostate carcinoma PC-3 cells expressing 8S-LOX or 15S-LOX-2. The growth rate of cells measured by colorimetric assay was reduced by expression of 8S-LOX and 15S-LOX-2. The addition to enzyme-expressing cells of arachidonic acid enhanced the growth suppressive effect, whereas the expression of catalytically inactive mutants did not affect cell growth, suggesting that the effect was product-dependent. DNA microarray and quantitative reverse transcription-PCR analyses revealed that the c-myc mRNA coding region determinant-binding protein/insulin-like growth factor II mRNA-binding protein 1 (CRD-BP/IMP-1), known as an oncofetal protein, was down-regulated in 8S-LOX- and 15S-LOX-2-expressing PC-3 cells. Targeted knockdown of CRD-BP/IMP-1 resulted in inhibition of the DNA synthesis rate of PC-3 cells as measured by bromodeoxyuridine incorporation. We propose that expression of 8S-LOX and 15S-LOX-2 suppresses CRD-BP/IMP-1 expression, resulting in inhibition of human prostate carcinoma PC-3 cell proliferation.
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Biochemistry & Molecular Biology Notes
  • Eun-Mi PARK, Young-Ok KIM, Bo-Hye NAM, Hee Jeong KONG, Woo-Jin KIM, Sa ...
    2009 Volume 73 Issue 8 Pages 1856-1859
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    We isolated a homolog of cathepsin D from the cDNA library of the olive flounder kidney. The olive flounder cathepsin D transcript consisted of 1,733 bp that encoded a polypeptide of 396 amino acids. The overall similarity between olive flounder cathepsin D and other cathepsin Ds was very high, with the highest amino acid sequence identity to barramundi perch (89%). RT-PCR revealed that cathepsin D was expressed in almost all tissues, with high expression in the liver, intestine, kidney, skin, and spleen. The accumulation of cathepsin D mRNA after bacterial infection, as determined by RT-PCR, was constitutive and increased greatly after bacterial infection.
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  • Yoshihiro MATSUSHIMA, Osamu SHIROTA, Ruri KIKURA-HANAJIRI, Yukihiro GO ...
    2009 Volume 73 Issue 8 Pages 1866-1868
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Psilocybe argentipes is a hallucinogenic mushroom. The present study examined the effects of P. argentipes on marble-burying behavior, which is considered an animal model of obsessive-compulsive disorder. P. argentipes significantly inhibited marble-burying behavior without affecting locomotor activity as compared with the same dose of authentic psilocybin. These findings suggest that P. argentipes would be efficient in clinical obsessive-compulsive disorder therapy.
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  • Kazuki NAKASHIMA, Aiko ISHIDA, Masaya KATSUMATA
    2009 Volume 73 Issue 8 Pages 1869-1871
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Previous studies have shown that the muscle protein degradation rates of broiler are lower than those of layer chickens. In this study, we assessed proteolytic-related gene expression in the pectoralis muscle of layer and broiler chickens. The mRNA levels of atrogin-1/MAFbx and proteasome C2 subunit, but not those of ubiquitin, m-calpain large subunit, cathepsin B, or caspase-3, were lower in the skeletal muscle of the broilers than in the layers at 7 and 14 d of age. We infer that the lower muscle protein degradation of broilers than of layers at least partly relates to lower mRNA expression of atrogin-1/MAFbx and proteasome C2 subunit in the skeletal muscle of broilers.
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  • Tetsuya CHUJO, Naho SUGIOKA, Yuka MASUDA, Naoto SHIBUYA, Tetsuo TAKEMU ...
    2009 Volume 73 Issue 8 Pages 1901-1904
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    OsWRKY53, a chitin oligosaccharide elicitor-responsive rice WRKY gene, has been found to be involved in defense responses in rice. We identified three tandem W-box elements, putative recognition sites for WRKY transcription factors, as cis elements that are essential to the elicitor-responsiveness of OsWRKY53 by deletion and mutation analysis of the promoter by dual luciferase assay.
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Food & Nutrition Science Regular Papers
  • Shigeaki UENO, Toru IZUMI, Tomoyuki FUJII
    2009 Volume 73 Issue 8 Pages 1699-1703
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    The relative drying rate of samples (RDR), which is the ratio of the drying rate of pretreated samples to that of untreated ones, might be used as a tool to investigate the damage to cells of agroproducts induced by high-pressure treatment. Damage to cells induced by high pressure was estimated by comparing the RDR after high-pressure pretreatment with the RDR after chloroform-vapor, heat, and freeze-thaw pretreatments of Japanese radish samples. The RDR after high-pressure pretreatment was similar to the RDR after chloroform-vapor pretreatment, and was lower than for heat, and for freeze-thaw pretreatment. For agroproducts, high-pressure treatment is thus comparatively moderate.
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  • So-Young CHUNG, Young-Kwon SEO, Jung-Min PARK, Min-Jae SEO, Jung-Keug ...
    2009 Volume 73 Issue 8 Pages 1704-1710
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Rice bran contains various polyphenolic compounds with anti-oxidative activities, and it has long been known to inhibit melanogenesis, but the inhibition mechanism has not been fully elucidated. Cofermentation of rice bran with Lactobacillus rhamnosus and Saccharomyces cerevisiae significantly reduced the cytotoxicity of the resulting extract to B16F1 melanoma cells. Marked reduction of α-melanocyte stimulating hormone (MSH) induced melanin synthesis was also observed upon treatment with fermented rice bran extract but it had no direct inhibitory effect on tyrosinase activity, while the intracellular tyrosinase activity was reduced by the extract. This result was further confirmed by an immunoblot assay measuring the level of tyrosinase protein. In addition, the expression of microphthalmia-associated transcription factor (MITF), a key regulator of melanogenesis, was significantly decreased by the extract. All together, the fermented rice bran extracts showed an inhibitory effect on melanogenesis through downregulation of MITF, along with reduced cytotoxicity.
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  • Changyong XUE, Yinghua LIU, Jin WANG, Zixin ZHENG, Yuehong ZHANG, Yong ...
    2009 Volume 73 Issue 8 Pages 1711-1717
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Two groups of Chinese hypertriacylglycerolemic subjects were recruited and randomized to medium- and long-chain triacylglycerols (MLCT) oil or long-chain triacylglycerols (LCT) oil. Two subgroups were divided by age at less or more 60 years in both groups. Both oils were consumed at 25–30 g daily for 8 weeks. Anthropometry, blood biochemicals, and computed tomography (CT) scanning were done at the initial and final times. In subjects of age less than 60 years on MLCT, the body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), body fat, total fat area, and subcutaneous fat area were significantly lower than those of the initial values, and the change values in these indicators and visceral fat area lowered significantly as compared with those on LCT. The levels of apoB, apoA2, apoC2, and apoC3 decreased significantly, and the change in values in the levels of triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), apoA1, apoB, apoA2, apoC2, apoC3 were significantly lower on MLCT of age under 60 years as compared with those on LCT.
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  • Jae-Sung LEE, Kohsuke OKA, Mie OBARA, Megumi NISHIMUKAI, Yung-Choon YO ...
    2009 Volume 73 Issue 8 Pages 1732-1740
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    We optimized the isolation protocol for intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) from the rat small intestine, and LPLs from even the rat large intestine. The major population of IELs in the small intestine was considered to be from the villus epithelia. The cytotoxicity of mucosal leukocytes was comparable among isolated fractions from both the small and large intestines, regardless of the population differences. Further analyses of the cells collected from other lymphoid tissues demonstrated that CD161+ cells selectively accumulated in the intestinal lamina propria and did not recirculate through the lymph ducts. Our modified isolation protocol enables the collection of mucosal immune cells from the rat intestines without any deterioration of cell function and could contribute to a better understanding of dietary influences on the mucosal immune system.
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  • Chinfang LIU, Kazuko SUGITA, Ken-ichi NIHEI, Koichi YONEYAMA, Hideyuki ...
    2009 Volume 73 Issue 8 Pages 1741-1747
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    To assess the digestion and assimilation of gelatin and gelatin hydrolysates, the in situ absorption of typical hydroxyproline-containing dipeptides, Pro-Hyp, Hyp-Gly, Ser-Hyp Ala-Hyp, and pentadecapeptide, (Pro-Hyp-Gly)5, was investigated in the rat small intestine. During vascular perfusion after the injection of Hyp-Gly, Pro-Hyp and (Pro-Hyp-Gly)5 into the jejunum, peptide-form Hyp but not free-Hyp gradually increased in the perfusate. In contrast, in the case of Ser-Hyp and Ala-Hyp, both free- and peptide-form Hyp rapidly increased. The presence of these dipeptides and the pentadecapeptide in the perfusates was confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), using multiple reaction monitoring (MRM). Some digestive and absorbed forms from (Pro-Hyp-Gly)5 were identified as Gly-(Pro-Hyp-Gly)4, (Pro-Hyp-Gly)4, Gly-(Pro-Hyp-Gly)3, (Pro-Hyp-Gly)3, Gly-(Pro-Hyp-Gly)2, and (Pro-Hyp-Gly)2 by MALDI-TOF/MS. The dipeptide hydrolase activity in intestinal mucosa toward Pro-Hyp and Hyp-Gly was extremely low, while Ser-Hyp and Ala-Hyp were substantially hydrolyzed in the cytosol. These results suggest that Hyp-peptides were resistant to intracellular hydrolysis and that a significant amount of these peptides was transported across the intestinal wall and may enter the portal circulation in an intact form.
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  • Yu-Shan WEI, Being-Sun WUNG, Yuan-Chun LIN, Chia-Wen HSIEH
    2009 Volume 73 Issue 8 Pages 1757-1763
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Ganoderma tsugae is a medicinal fungus with several biological activities. It has long been used as a folk remedy for the promotion of health and longevity in China and other oriental countries. Here, a bioactive fraction of G. tsugae was progressively purified to be enriched in the activity of cytoprotective enzymes. The highest bioactivity was detected in the 20% EtOH-precipitated fraction, which was prepared from submerged fermentation filtrate of G. tsugae. Following further purification by gel filtration chromatography and acetone extraction, the most bioactive fraction, F5-2, was identified as a peptidoglycan-like compound. Extracts of G. tsugae (F5-2) induced heme oxygenase-1 (HO-1) and thioredoxin reductase-1 (TrxR1) expression in endothelial cells by increasing NF-E2-related factor-2 (Nrf2) nuclear translocation. Pretreatment with F5-2 increased intracellular glutathione (GSH) and protected against H2O2, suggesting that induction of these antioxidant enzymes is important in protection against oxidative stress. Hence the bioactive peptidoglycan-like compound from G. tsugae might protect endothelial cells.
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  • Fumie SHINOMIYA, Yasunori HAMAUZU, Takeshi KAWAHARA
    2009 Volume 73 Issue 8 Pages 1773-1778
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    We examined the effect of a crude hot-water extract (HW) of quince (Cydonia oblonga Miller) fruit on type I allergy in vivo and in vitro. The oral administration of the quince HW-added diet to NC/Nga mice for 63 d showed a significant decrease in the development of atopic dermatitis-like skin lesions under conventional conditions. The concentration of IgE in the serum collected from mice fed with quince HW was also lowered in a dose-dependent manner. Moreover, we found that quince HW inhibited the release of β-hexosaminidase from rat basophilic leukemia cell line RBL-2H3 after a 24-h treatment. The quince HW fraction of less than 3 kDa reduced the mRNA expression of the high-affinity IgE receptor (FcεRI) γ subunit. These results suggest that quince HW had an inhibitory effect on type I allergy by suppressing IgE production and IgE-mediated degranulation.
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  • Carsten MÜLLER, Kristina ULLMANN, Andrea WILKENS, Peter WINTERHAL ...
    2009 Volume 73 Issue 8 Pages 1831-1836
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    The health promoting effects of a grapevine-shoot extract named Vineatrol®30, which contains resveratrol (Resv) as well as considerable amounts of Resv oligomers, have recently been investigated. In the present study, we analyzed the free radical scavenging capacity, the ability to inhibit lipid peroxidation, and the capacity to enhance the human glutathione peroxidase 1 (GPx) and the human superoxide dismutase 1 (SOD) gene promoter activities of Vineatrol®30. Vineatrol®30 was able to scavenge the 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical cation and led to concentration-dependent inhibition of lipid peroxidation, Vineatrol®30 not being superior to Resv alone in both cases. Vineatrol®30 also enhanced the gene promoter activities of human GPx and SOD expressed in V79 cells, whereas this effect could not be demonstrated for Resv. In summary, the results presented in this study show that the Vineatrol®30 grapevine-shoot extract is a free radical scavenger and potent antioxidant at non-cytotoxic concentrations.
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  • Tomoo KONDO, Mikiya KISHI, Takashi FUSHIMI, Shinobu UGAJIN, Takayuki K ...
    2009 Volume 73 Issue 8 Pages 1837-1843
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Acetic acid (AcOH), a main component of vinegar, recently was found to suppress body fat accumulation in animal studies. Hence we investigated the effects of vinegar intake on the reduction of body fat mass in obese Japanese in a double-blind trial. The subjects were randomly assigned to three groups of similar body weight, body mass index (BMI), and waist circumference. During the 12-week treatment period, the subjects in each group ingested 500 ml daily of a beverage containing either 15 ml of vinegar (750 mg AcOH), 30 ml of vinegar (1,500 mg AcOH), or 0 ml of vinegar (0 mg AcOH, placebo). Body weight, BMI, visceral fat area, waist circumference, and serum triglyceride levels were significantly lower in both vinegar intake groups than in the placebo group. In conclusion, daily intake of vinegar might be useful in the prevention of metabolic syndrome by reducing obesity.
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  • Pattana KAKUMYAN, Marie KATO, Makita HAJIKA, Kenji MATSUI
    2009 Volume 73 Issue 8 Pages 1844-1848
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Flavor properties are important factors of soybean seeds in their utilization as food materials. In order to isolate novel varieties and mutants of soybean having preferable flavor properties, a simple and efficient screening system was established using an automated headspace sampler coupled to gas chromatography. With this system, five major volatile compounds were analyzed within 12 min. By applying this screening system to 626 soybean varieties collected worldwide, we isolated four soybean varieties that showed unique compositions of volatile compounds. Through biochemical analysis, it was found that the uniqueness of three of them was possibly independent of lipoxygenase enzyme, and thus perhaps this screening system can expand the subject of flavor properties beyond lipoxygenase and thus be useful in discovering new types of soybeans.
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  • Kiyoshi YAMADA, Kanako SATO, Satoru MORISHITA, Shuichi KAMINOGAWA, Mam ...
    2009 Volume 73 Issue 8 Pages 1849-1855
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Studies of the physiological functions of intestinal epithelial cells (IECs) have been limited by the difficulty of primary culture of IEC. We established a method for primary culture of mouse IEC by culturing fragments of fetal small intestines pretreated with EDTA. This method reproducibly resulted in the expansion of cytokeratin-positive epithelial cells, and vigorous expansion of the epithelial cells was observed only from intestinal fragments of embryonic days 15-16. These cells expressed alkaline phosphatase activity and major histocompatibility complex (MHC) class II molecules, indicating the mature phenotype of IEC in a small intestine. The cells also presented antigens to CD4+ T cells. Furthermore, the cells expressed various cytokines and chemokines, and the expression was enhanced by bacterial stimulation. These results indicate that the primary-cultured mouse IEC prepared by the method established here can be a beneficial tool in study of the functions of IECs, especially in mucosal immunity.
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Food & Nutrition Science Notes
Microbiology & Fermentation Technology Regular Papers
  • Masahiko MINAMI, Kazumi SUZUKI, Akifumi SHIMIZU, Tomohiro HONGO, Takai ...
    2009 Volume 73 Issue 8 Pages 1722-1731
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    We constructed a LongSAGE (Long Serial Analysis of Gene Expression) library from a 3-d culture of Phanerochaete chrysosporium supplemented with atropine, which inhibits the production of lignin-degrading enzymes. The library (the atropine library) contains 13,108 LongSAGE tags and 6,783 unique tags. The gene expression profile represented by the tags was compared with those of two previously constructed libraries, one of which was constructed using 2-d cultures in which the fungus had not yet produced ligninolytic enzymes (the 2-d library) and the other was constructed using 3-d cultures in which the fungus had just started to produce the enzymes (the 3-d library). We found a total of 595 genes that were at least twice more highly or at least twice less highly expressed in the 3-d library than in the 2-d library or the atropine library, and the fluctuations were statistically significant. The relationships among these 595 genes were considered using cluster analysis. Of the 595 genes, 164 showed expression patterns similar to those of four ligninolytic enzyme genes, which were more expressed on day 3 than under any other conditions. Many of these 164 genes comprised genes possibly involved in lignin degradation, lipid metabolism, xenobiotic degradation, stress response, or signal transduction pathways.
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  • Marie NISHIMURA, Junji FUKADA, Akihiro MORIWAKI, Takashi FUJIKAWA, Mih ...
    2009 Volume 73 Issue 8 Pages 1779-1786
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    The APSES protein family includes important transcriptional regulators of morphological processes in ascomycetes. We identified a deletion mutant of the APSES protein Mstu1 in Magnaporthe grisea that showed reduced conidiation and mycelial growth. Mstu1 formed a number of appressoria comparable to the wild type, although appressorium formation was delayed. In M. grisea, rapid transfer of conidial glycogen and lipid droplets to incipient appressoria is required for appressorial turgor generation, which the fungus uses to penetrate plant cuticles. Appressorial turgor was low in mstu1 and the mutant was deficient in appressorium-mediated invasion of rice leaves. The transfer of conidial glycogen and lipid droplets was remarkably delayed in mstu1, and a consequent delay in degradation of these conidial reserves was observed. Our results indicate that Mstu1 is required for appressorium-mediated infection due to its involvement in the mobilization of lipids and glycogen.
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  • Hiroshi HABE, Yuko SHIMADA, Tokuma FUKUOKA, Dai KITAMOTO, Masayuki ITA ...
    2009 Volume 73 Issue 8 Pages 1799-1805
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Gluconobacter sp. NBRC3259 converted glycerol to glyceric acid (GA). The enantiomeric composition of the GA produced was a mixture of DL-forms with a 77% enantiomeric excess of D-GA. After culture conditions, such as initial glycerol concentration, types and amounts of nitrogen sources, and initial pH, were optimized, Gluconobacter sp. NBRC3259 produced 54.7 g/l of GA as well as 33.7 g/l of dihydroxyacetone (DHA) from 167 g/l of glycerol during 4 d of incubation in a jar fermentor with pH control. GA production from raw glycerol samples, the main by-product of the transesterification process in the biodiesel production and oleochemical industries, was also evaluated after proper pretreatment of the samples. Using a raw glycerol sample with activated charcoal pretreatment, 45.9 g/l of GA and 28.2 g/l of DHA were produced from 174 g/l of glycerol.
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  • Shigehito IKUSHIMA, Toshio FUJII, Osamu KOBAYASHI, Satoshi YOSHIDA, Ar ...
    2009 Volume 73 Issue 8 Pages 1818-1824
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Polylactic acid is receiving increasing attention as a renewable alternative for conventional petroleum-based plastics. In the present study, we constructed a metabolically-engineered Candida utilis strain that produces L-lactic acid with the highest efficiency yet reported in yeasts. Initially, the gene encoding pyruvate decarboxylase (CuPDC1) was identified, followed by four CuPDC1 disruption events in order to obtain a null mutant that produced little ethanol (a by-product of L-lactic acid). Two copies of the L-lactate dehydrogenase (L-LDH) gene derived from Bos taurus under the control of the CuPDC1 promoter were then integrated into the genome of the CuPdc1-null deletant. The resulting strain produced 103.3 g/l of L-lactic acid from 108.7 g/l of glucose in 33 h, representing a 95.1% conversion. The maximum production rate of L-lactic acid was 4.9 g/l/h. The optical purity of the L-lactic acid was found to be more than 99.9% e.e.
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  • Naoya FUJITA, Futoshi SUMISA, Kazutoshi SHINDO, Hiroki KABUMOTO, Akira ...
    2009 Volume 73 Issue 8 Pages 1825-1830
    Published: August 23, 2009
    Released: August 23, 2009
    [Advance publication] Released: August 07, 2009
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    Two vectors, pT7NScamAB and pRED, have been used for the functional expression of bacterial class I cytochrome P450 (P450) genes in Escherichia coli, which utilize putidaredoxin reductase (CamA) and putidaredoxin (CamB), and the reductase domain of a self-sufficient P450RhF respectively, for electron transfer from NAD(P)H to a P450 protein. We here compared the efficiency of bioconversion with the two vectors towards n-octane, cyclohexane, n-butylbenzene, and 2-n-butylbenzofuran using two well-characterized CYP153A genes, aciA and CYP153A13a (P450balk). As for n-octane bioconversion, aciA and pT7camAB was the best combination for the production of 1-octanol and 1,8-octanediol. As for the bioconversion of cyclohexane, n-butylbenzene and 2-n-butylbenzofuran, CYP153A13a with pRED achieved the most efficient bioconversion, as compared by conversion ratio per active CYP153A protein content. It was also found that 2-n-butylbenzofuran is biotransformed into 4-benzofuran-2-yl-butyric acid via 4-benzofuran-2-yl-butan-1-ol with E. coli cells expressing CYP153A.
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Microbiology & Fermentation Technology Notes
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