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1.
An enzyme which catalyzes the oxidation of poly(vinyl alcohol) (PVA) has been purified from a fraction adsorbed to DEAE-Sephadex at pH 7.0 from PVA-degrading enzyme activities produced by a bacterial symbiotic mixed culture in a culture broth when the culture was grown in a minimal medium where PVA served as a sole source of carbon and energy. The enzyme was separated from a coexisting oxidized PVA hydrolase by dye-ligand chromatography on Matrex Gel Blue A. The purified enzyme was homogeneous as judged by polyacrylamide gel electrophoreses in the absence and presence of SDS.The enzyme is a single polypeptide with a molecular weight of about 40,000 and has an isoelectric point of 4.5. The amino acid composition of the enzyme has been determined and found to have no histidine. The N- and C-terminal amino acid residues are both alanine. The enzyme solution is pink and shows absorption maxima at 276, 364, and 469 nm. One atom of non-heme iron has been detected per molecule in the enzyme.The enzyme catalyzes the oxidation of PVA and also of various low molecular weight secondary alcohols to the corresponding ketones with the production of H202 and the consumption of 02. The molar ratio of these ketones, H202 and 02 is 1:1:1. The most effective electron acceptor is 02, while 2,6-dichlorophenolindophenol and nitro blue tetrazolium also serve as the acceptor with efficiencies to 02 of about 31 and 16%, respectively. The enzyme is, therefore, considered to be a secondary alcohol oxidase.The enzyme is most active at pH 7.0 and at 45°C and is stable between pH 5.0 and 9.0 and at temperatures below 45°C. The activity is inhibited by Hg2+ and is restored by the addition of reduced glutathione, although p-chloromercuribenzoate has no effect.The enzyme shows a common antigenicity in immunodiffusion and neutralization reactions with antisera to a secondary alcohol oxidase previously isolated from another fraction adsorbed on SP-Sephadex at pH 7.0 of the PVA-degrading enzyme activities [Agric. Biol. Chem., 43, 1225 (1979)]. The relations between these two secondary alcohol oxidases are discussed. 相似文献
2.
An alternative synthesis of (±)-tubaic acid (I), a key intermediate compound of rotenone synthesis, has been accomplished by the Wittig reaction. 相似文献
3.
《Bioscience, biotechnology, and biochemistry》2013,77(10):1713-1715
The fungitoxic sesquiterpene (±)-chokolic acid A (1) was synthesized stereoselectively by starting from 2-methoxycarbonyl-(3-isopropenyl)cyclopentanone (2) in a 9% overall yield from 10 steps. 相似文献
4.
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
5.
Daniel W. Norbeck Hing L. Sham William Rosenbrook Thomas Herrin Jacob J. Plattner 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1383-1391
Abstract Synthesis of the novel phosphonate isostere of the monophosphate of (±)Cyclobut-G and its biological activities against HSV-1 and HSV-2 in Vero cells are reported. The cyclobutane ring was constructed by a [2+2] thermal cycloaddition. The relative stereochemistry of the substituents on the ring was determined by NOE experiments. 相似文献
6.
《Bioscience, biotechnology, and biochemistry》2013,77(11):1807-1809
(±)-Homosarkomycin (2) and (±)-rosaprostol (3) were synthesized from (±)-methyl 2-oxo-bicyclo[3.1.0]hexane-1-carboxylate (1) by using the nucleophilic ring opening reaction on the double-activated cyclopropane ring as the key step. 相似文献
7.
Yasuhiro Yamada Kota Hatano Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(10):1536-1540
(±)-Lamprolobine, the (+)-enatiomer of which was isolated from the leaves of Lamprolobium fruticosum, and (±)-epilamprolobine were synthesized from δ-valerolactam. 相似文献
8.
Yasuhiro Yamada Tomio Emori Shinichi Kinoshita Hirosuke Okada 《Bioscience, biotechnology, and biochemistry》2013,77(3):649-652
(±)-Azetidine-2-carboxylic acid and 3-substituted-2-pyrrolidinones were synthesized from 2-pyrrolidinone via 3-bromo-2-methoxy-1-pyrroline (IIIa). The bromide (IIIa) was obtained by the bromination of 2-methoxy-l-pyrroline using NBS. 相似文献
9.
Takeshi Kitahara Katsutoshi Miura Yasuhiro Warita Yoshikazu Takagi Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(4):1129-1133
A novel synthesis of ( ± )-methyl epijasomonate (2) and the first synthesis of ( ± )-methyl cucurbate (4) were achieved starting from 2-allylcyclohexane-1,3-dione (8). The synthetic epimer 2 had a stronger jasmin flavor than the trans-isomer 1 with 95% purity. 相似文献
10.
Yuichi Yoshimura Kenji Kitano Mikari Watanabe Hiroshi Satoh Shinji Sakata Shinji Miura 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1103-1106
Abstract We have synthesized 4′-thioDMDC, 4′-thiogemcitabine, and 4′-thioarabinonucleosides, as potential antitumor and antiviral agents, originated from D-glucose. Biological activities of these compounds are also described. 相似文献
11.
Toyofumi Yamaguchi Kunie Sato Mineo Saneyoshi 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):529-532
Abstract Several sugar-modified 2-(p-n-butylanilino)-2′-deoxyadenosine analogues, including arabino and 2′(R)-azido-2′-deoxy analogues and their 5′-triphosphates were synthesized. These nucleosides thus obtained exhibited moderate cytotoxicity against P-388 leukemic cells in culture (IC50 = 13–24 μ). In contrast to above results, the 5′-triphosphates have been shown to exert strong and selective inhibitory effects on mammalian DNA polymerase α (Ki= 0.02–0.04 μ). 相似文献
12.
13.
Junichi Oda Hiroshi Fukami Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(1):59-63
(±)Hydroxytremetone (III) has been synthesized from 2-(α-hydoxyisopropyl)-6-hydroxycoumaran (V b) via its O-acetate V c by dehydration with phosphorus tribromide in pyridine solution, followed by acylation with a mixture of trifluoroacetic anhydride and acetic acid. Isohydroxytremetone (IX b) was also synthesized. 相似文献
14.
Hiroyoshi Omokawa Kyohei Yamashita 《Bioscience, biotechnology, and biochemistry》2013,77(9):1731-1734
Total synthesis of (±)-deguelin was described. Thermal rearrangement of 1,1-dimethyl-2-propynyl ethers of β-resorcinaldehyde and 2,3-dimethoxy-9-hydroxy-rotoxen-12(6H)-one afforded β-tubaaldehyde and dehydrodeguelin respectively. 2,2-Dimethyl-5-hydroxybenzopyran-6-yl 3-(3,4-dimethoxyphenoxy)-1-propynyl ketone was converted to the corresponding benzopyran-6-yl benzopyran-4-yl ketone, which was treated with sodium acetate to give (±)-deguelin. 相似文献
15.
The synthesis of (±)-licarin-B, a neolignan of Licaria aritu Ducke (Lauraceae), was achieved by pyrolysis of 3-hydroxy-3-piperonyl-1-propyl-2-methoxy-4-(E)-propenylphenyl ethers. 相似文献
16.
The enzymatic properties of P2-2 enzyme were determined by using cells of M. radiodurans. The enzyme was: most active at 60°C incubation temperature, stable at 40°C in neutral buffer, and inactivated by heating at 80°C for 15min. Maximal lytic activity occurred at pH 8.5 in Tris-HCl buffer. The range of enzyme stability was between pH 5.5 and 8. Bivalent metal ions, p-chloromercuribenzoate and monoiodo acetate inhibited lytic activity. The molecular weight was estimated to be 16,000 daltons by gel filtration on Sephadex G-75. The enzymatic digestion of peptidoglycans from the cell walls of M. radiodurans and M. lysodeikticus liberated free amino groups, but neither reducing groups nor N-acetylhexosamine, indicating that the enzyme was an endopeptidase. From analysis of the N-terminal amino acids of the digests, it is suggested that the P2-2 enzyme cleaves the peptide bond at the carboxyl group of D-alanine in peptidoglycan. 相似文献
17.
Corinne Bacchelli Roger Condom Nadia Patino Anne-Marie Aubertin 《Nucleosides, nucleotides & nucleic acids》2013,32(3):567-584
Abstract We describe the synthesis of two series of acyclonucleosides: carbaacyclonucleosides and 1′-oxaacyclonucleosides which possess the same aglycone as clitocine 3 which is a natural nucleoside exhibiting interesting biological properties. These compounds have been obtained by condensation of 4-aminobutanol or 3-silyloxypropoxyamine with 4,6-dichloro-5-nitropyrimidine. Structural modifications have been made on the heterocyclic base and the side chain to enhance their potential activity. 相似文献
18.
Akitami Ichihara Ryoji Kimura Kengo Oda Koichi Moriyasu Sadao Sakamura 《Bioscience, biotechnology, and biochemistry》2013,77(7):1879-1883
Synthesis of (±)-phyllostine, (±)-epoxydon, (±)-epiepoxydon, (±)-epoformin and (±)-epiepoformin by the retro-Diels—Alder reaction was described. 相似文献
19.
David Shire Pierre Blanchard Aly Raies Françhise Lawrence Malka Robert-Géro Edgar Lederer 《Nucleosides, nucleotides & nucleic acids》2013,32(1):21-31
Abstract The synthesis of new S-adenosyl-homocysteine (SAH) analogues substituted at the 5′-position is described. Their activity on cell transformation induced by Rous sarcoma virus (RSV) as well as their effect on cell growth and on replication of polyoma virus were also studied. The best results were obtained with compounds having a phenyl group at the 5′-position of adenosine. These molecules inhibit very strongly uridine uptake by cells. 相似文献