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Yoshihiko Obara Hiromichi Matsubara Katsura Munakata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1245-1246
A tobacco callus strain, OMT-53, was selected from many cultures as a desirable strain having high nicotine producing capacity. Several culture conditions were examined, aiming to get higher nicotine production with the callus strain, OMT-53. It was revealed that the nicotine production was remarkably enhanced when the callus tissues were cultured at a limited concentration of α-NAA in culture medium. The optimal concentrations of sucrose and nitrogen in the culture medium were 3 % and 840 mg N/L respectively. Some precursors in nicotine biosynthesis were examined, and only ornithine gave a slightly positive effect at 2x10-4m concentration. Cultures at 25°C produced the highest yield for nicotine. Considerable amounts of nicotine (ca. 20% of total nicotine) were also recognized in the culture medium. Under the best culture condition mentioned above, nicotine production in tobacco callus tissues has been elevated to 2.14% on D.W, basis at 4 weeks’ culture. This value is near to that of the intact tobacco plants. 相似文献
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Takeshi Tabuchi Nobufusa Serizawa Sadahiro Ohmomo 《Bioscience, biotechnology, and biochemistry》2013,77(12):2565-2566
Human lactoferrin was produced in genetically engineered rice. N-linked glycan structures of recombinant human lactoferrin were determined. The oligosaccharides liberated by hydrazinolysis were labeled with 2-aminopyridine (PA). The PA-labeled glycans were purified by reverse-phase and size-fractionation HPLCs. The structures of these glycans were identified by HPLC, exoglycosidase digestion, and matrix-assisted laser desorption/ionization time-of-flight (MALDI–TOF) mass spectrometry. The glycan structures determined were ManFucXylGlcNAc2 (3.4%), Man2FucGlcNAc2 (2.1%), Man3FucGlcNAc2 (2.5%), Man3FucXylGlcNAc2 (42.5%), two isomers of Man2FucXylGlcNAc2 (39.1%), Man3XylGlcNAc2 (6.5%), and Man2XylGlcNAc2 (3.9%). 相似文献
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《Cell Adhesion & Migration》2013,7(3):142-144
Transforming growth factor (TGFβ) prevents TH1 and TH2 differentiation and converts naïve CD4 cells into Foxp3-expressing T regulatory (Treg) cell1, 2. In sharp contrast, in the presence of pro-inflammatory cytokines, including IL-6, TGFβ not only inhibits Foxp3 expression but also promotes the differentiation of pro-inflammatory IL17-producing CD4 effector T (TH17) cells3-5. This reciprocal TGFβ-dependent differentiation imposes a critical dilemma between pro- and anti-inflammatory immunity and suggests that a sensitive regulatory mechanism must exist to control TGFβ-driven TH17 effector and Treg differentiation. A vitamin A metabolite, retinoic acid (RA), was recently identified as a key modulator of TGFβ-driven immune deviation capable of suppressing TH17 differentiation while promoting Foxp3+Treg generation 6-10. 相似文献
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Tetsuo Fukuzumi Hiroyasu Takahara Hajime Kaneko 《Bioscience, biotechnology, and biochemistry》2013,77(5):513-514
A new method determining the activity of tannin acyl hydrolase (tannase) was made. This method was based on the change in optical density of substrate tannic acid at 310 mμ. In this method, the error of measurement was about 1~3%, and many samples could be tested at one time because of its simplicity.The procedure was as follows; To four parts of substrate (0.350 w/v% of tannic acid dissolved in 0.05m citrate buffer, pH 5.5), one part of the enzyme solution was added.After t minutes reaction at 30°C, 0.1 part of the mixture was added to ten parts of 90% ethanol.The optical density of the ethanol solution at 310 mμ was measured. Tannase activity (unit/ml) was given by following equation. Where Et1 and Et2 mean the optical density of the ethanol solution at 310 mμ prepared after t1 and t2 minutes reaction, and one unit of the enzyme means the amount of the enzyme which is able to hydrolyze one μ mole of the ester bond in tannic acid in one minute.The substrate tannic acid used in this determining method was purified. It was composed of one mole of glucose and nine moles of gallic acid, and eight moles of which formed four moles of m-digallic acid. 相似文献
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Rui Li Peng Quan Dong-Fei Liu Fang-Di Wei Qing Zhang Qun-Wei Xu 《AAPS PharmSciTech》2009,10(4):1137-1144
The present work was aimed at the influence of ethanol on the complex formation of hydroxypropyl-β-cyclodextrin (HP-β-CD)
with oleanolic acid (OA) and ursolic acid (UA), two insoluble isomeric triterpenic acids. Phase solubility studies were carried
out to evaluate the solubilizing power of HP-β-CD, in association with ethanol, toward OA and UA. A mathematical model was
applied to explain and predict the solubility of OA and UA influenced by HP-β-CD and ethanol. The solid complexes were prepared
by evaporating the filtrate of samples which was prepared in different complexing media. The solubility of OA is much higher
than that of UA in all the tested aqueous solutions. The solubility of OA and UA can be increased over 900 and 200 times,
respectively, by forming complex with HP-β-CD. Ethanol (0.5%, v/v) can help the formation of OA-HP-β-CD complex, but is harmful to the formation of UA-HP-β-CD complex. Increasing solubility
in water can be achieved by adding ethanol into the complexing media, but the concentration of ethanol should be optimized.
The ring E of the chemical compounds has a great influence on the complexing process. 相似文献
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Dopaminergic activity is expected to be altered in patients with Huntington’s disease (HD) and be related to factors like
duration and severity of illness or patients’ specific symptomatology like dementia, depression, or psychotic features. We
assessed plasma homovanillic acid (pHVA) and plasma prolactin (pPRL), two correlates of dopaminergic activity, in 116 subjects
with CAG repeats expansion in the HD gene, 26 presymptomatic (18 females) and 90 with overt symptomatology (43 females). Patients
were evaluated using the Unified HD Rating Scale and the Total Functional Capacity Scale. Presence of dementia, depression,
and psychotic features were also assessed. The age range of the patients was 22–83 years, duration of illness from 0.5 to
27 years, and CAG repeat number from 34 to 66. A group of 60 age and sex matched healthy subjects served as control group.
Plasma PRL in subjects at risk and in neuroleptic-free patients, evaluated separately for males and females, did not differ
from controls. Plasma HVA levels did not differ from controls in the group of presymptomatic subjects, but were significantly
higher in the patients group. This increase was positively associated mainly with severity of illness and functional capacity
of the patients, and not with presence of depression or dementia. Plasma HVA levels may be proven to be a peripheral index
of disease progression. Reducing dopaminergic activity may have not only symptomatic, but also neuroprotective effects in
HD. 相似文献
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We isolated a cDNA for basic class I chitinase (ChitiWb1). ChitiWb1 cDNA encodes a protein that consists of 315 amino acid residues and has a signal peptide. Northern blot analysis indicated that the class I chitinase mRNA in leaves and cultured cells of winged bean was increased by treatments with NaCl, KCl, CaCl2, mannitol or saccharose, but not with abscisic acid. Thus, class I chitinase expression was shown to be up-regulated by osmotic stress. 相似文献
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Akira Kaji Masayuki Sato Noboru Shinmyo Masaaki Yasuda 《Bioscience, biotechnology, and biochemistry》2013,77(10):1729-173
An acid β-d-galactosidase was purified from the culture filtrate of Corticium rolfsii IFO 6146 by a combination of QAE-Sephadex A-50 and SP-Sephadex C-50 chromatography. The maximum activity of the enzyme towards p-nitrophenyl β-D-galactopyranoside was found to be at pH 2.0 to 2.5 and the enzyme was fairly active at pH 1.5 to l.8. The enzyme was quite stable over a pH range 2.0 to 8.0 at 2°C for 72 hr. The enzymic activity was clearly inhibited by Hg2+. Km value was determined to be 3.84 × 10?4 m, and Vmax was calculated to be 6.9 μ moles per min per mg for p-nitrophenyl β-d-galactopyranoside. Contrary to high activity on the synthetic galactoside, reaction velocity was small when the enzyme acted on lactose. 相似文献
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Oxidative damage has been implicated to be a major causative factor in the decline in physiological functions that occur during
the ageing process. Mitochondria are known to be a rich source for the production of free radicals and, consequently, mitochondrial
components are susceptible to lipid peroxidation (LPO) that decreases respiratory activity. In the present investigation,
we have evaluated mitochondrial LPO, 8-oxo-dG, oxidized glutathione, reduced glutathione, ATP, lipoic acid, TCA cycle enzymes
and electron transport chain (ETC) complex activities in the brain of young versus aged rats. In aged rats, the contents of
LPO, oxidized glutathione and 8-oxo-dG were high whereas reduced glutathione, ATP, lipoic acid, TCA cycle enzymes and ETC
complex activities were found to be low. Lipoic acid administration to aged rats reduced the levels of mitochondrial LPO,
8-oxo-dG and oxidized glutathione and enhanced reduced glutathione, ATP, lipoic acid and ETC complex activities. In young
rats lipoic acid administration showed only minimal lowering the levels of LPO, 8-oxo-dG and oxidized glutathione and slight
increase in the levels of reduced glutathione, ATP, lipoic acid, TCA cycle enzymes and ETC complex activities. These findings
suggest that the dithiol, lipoic acid, provides protection against age-related oxidative damage in the mitochondria of aged
rats. 相似文献
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Katrina L. Bogan Charles Evans Peter Belenky Peng Song Charles F. Burant Robert Kennedy Charles Brenner 《The Journal of biological chemistry》2009,284(50):34861-34869
Recently, we discovered that nicotinamide riboside and nicotinic acid riboside are biosynthetic precursors of NAD+, which are utilized through two pathways consisting of distinct enzymes. In addition, we have shown that exogenously supplied nicotinamide riboside is imported into yeast cells by a dedicated transporter, and it extends replicative lifespan on high glucose medium. Here, we show that nicotinamide riboside and nicotinic acid riboside are authentic intracellular metabolites in yeast. Secreted nicotinamide riboside was detected with a biological assay, and intracellular levels of nicotinamide riboside, nicotinic acid riboside, and other NAD+ metabolites were determined by a liquid chromatography-mass spectrometry method. A biochemical genomic screen indicated that three yeast enzymes possess nicotinamide mononucleotide 5′-nucleotidase activity in vitro. Metabolic profiling of knock-out mutants established that Isn1 and Sdt1 are responsible for production of nicotinamide riboside and nicotinic acid riboside in cells. Isn1, initially classified as an IMP-specific 5′-nucleotidase, and Sdt1, initially classified as a pyrimidine 5′-nucleotidase, are additionally responsible for dephosphorylation of pyridine mononucleotides. Sdt1 overexpression is growth-inhibitory to cells in a manner that depends on its active site and correlates with reduced cellular NAD+. Expression of Isn1 protein is positively regulated by the availability of nicotinic acid and glucose. These results reveal unanticipated and highly regulated steps in NAD+ metabolism. 相似文献
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Deoxyribonucleic acid (DNA) molecules having a mean length of 5.8 mum were released from purified Bacillus subtilis bacteriophage phi29 with 2 m sodium perchlorate. Small 0.1 to 0.2-mum molecules were also detected in these DNA preparations. Since intact single chains annealed to form linear duplex molecules, phage phi29 DNA was found to be nonpermuted. The molecular weights of single chains of phi29 DNA were approximately half that of native DNA, as determined by analytical band sedimentation in CsCl, indicating that phi29 DNA is composed of two continuous polynucleotide chains. The molecular weight values of native and annealed phi29 DNA from sedimentation agreed with the molecular weight values obtained from electron microscopy. The infectivity of phi29 DNA was reduced to a low level by alkaline denaturation and was partially restored by annealing. 相似文献
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Itsuo Ichimoto Kichitaro Fujii Chuji Tatsumi 《Bioscience, biotechnology, and biochemistry》2013,77(8):979-989
The reactions of kojic acid and its related γ-pyrones with anhydrous hydrazine have been investigated. Kojic acid and hydrazine gave 3,6-dihydroxy methyl-4-охо-1,4-dihydro- pyridazine and 3-hydroxymethyl-pyrazolyl-(5)-glycoloyl-hydrazone, respectively, in 65% and 21% yields. The same reaction occured in the case of allomaltol and pyromeconic acid and gave the analogous results. On the other hand, 5-methoxykojic acid was allowed to react with hydrazine and afforded 1-amino-2-hydroxymethyl-5-methoxy-γ-pyridone and α[3-hydroxymethyl-pyrazolyl-(5)]-α-methoxy-acetaldehyde-hydrazone, respectively. The structural elucidation of these products could be fully substantiated by chemical evidences and spectroscopic data. The mechanisms for the reactions are also discussed. 相似文献
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Kyohei Yamashita Eiki Nagano Takayuki Oritani 《Bioscience, biotechnology, and biochemistry》2013,77(6):1441-1442
Nuclease activity associated with cells and protoplasts was analyzed by agarose gel electrophoresis. Datura innoxia protoplasts were found to possess a high exonuclease activity. On the other hand, Datura innoxia cells had an endonuclease activity, but no apparent exonuclease. The exonucleases from the protoplasts were active at pH 5 and 6, but not at pH 9. Endonuclease activity from the cells was also inhibited at pH 9. Cultured cells of Daucus carota, Glycine max, Pisum sativum and Vicia hajastana had endonuclease activity, but did not exhibit exonuclease activity. Nicotiana suaveolens cells had both types of nuclease activity. On the other hand, cells from cereals such as Triticum monococcum, Oryza sativa, and Zea mays had active exonuclease activity. 相似文献
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Itsuo Ichimoto Kichitaro Fujii Chuji Tatsumi 《Bioscience, biotechnology, and biochemistry》2013,77(4):325-330
An excellent synthetic method of maltol from kojic acid has been established. By Mannich reaction with formaldehyde and dimethylamine, comenic acid gave the mono-Mannich derivative which was reduced to 6-methyl comenic acid. The acid was converted to maltol in good yield by decarboxylation with copper powder or KC–400 (tetra-chloro-diphenyl).Hydroxymethylations of kojic, comenic and pyromeconic acids with formaldehyde in alkaline medium yielded the corresponding methylol derivatives which were converted to 6-methyl kojic acid, 6-methyl comenic acid and maltol in good yields, respectively, by reduction with stannous chloride. Oxidation of 6-methyl kojic acid with chromic anhydride and acetic acid gave 6-methyl comenic acid. 相似文献
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Itsuo Ichimoto Hiroo Ueda Chuji Tatsumi Kichitaro Fujii Fumio Sekido Seiichi Nonomura 《Bioscience, biotechnology, and biochemistry》2013,77(2):94-103
The Mannich reaction of kojic acid in both acidic and basic media was studied. Mono-Mannich derivatives (substitution at position 6) were obtained; the reactivity in basic medium was found to be somewhat greater than in acidic medium. Reduction of the Mannich derivatives with zinc dust and acetic acid gave a 6-methyl kojic acid (6-methyl-5-hydroxy-2-hydroxymethyl-γ-pyrone).Mono-Mannich base of pyromeconic acid was also prepared in a manner similar to that of kojic acid. From this Mannich base, maltol (2-methyl-3-hydroxy-γ-pyrone) was obtained by the reduction with zinc dust and acetic acid. 相似文献