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1.
Christoph Syldatk Andrea Stoffregen Frank Wuttke Reinhold Tacke 《Biotechnology letters》1988,10(10):731-734
Summary Thirty strains of microorganisms (bacteria, yeasts, fungi and green algae) were tested as resting free cells for their ability to transform acetyldimethylphenylsilane (1) enantioselectively into (R)-(1-hydroxyethyl)dimethylphenylsilane [(R)–2]. The biotransformations were monitored by GC (packed OV-17 column) and the enantiomeric purities of the products isolated were determined by HPLC (cellulose triacetate column, UV detection). All microorganisms tested were found to reduce 1 enantioselectively to give (R)-2. Under the test conditions used, the yeastTrigonopsis variabilis (DSM 70714) was found to exhibit the highest specific activity (1.5 mg product x g cell wet mass–1 x min–1), whereas the highest enantioselectivities were observed for the bacteriaAcinetobacter calcoaceticus (ATCC 31012) (>95% ee),Brevibacterium species (ATCC 21860) (90% ee) andCorynebacterium dioxydans (ATCC 21766) (>95% ee), the yeastCandida humicola (DSM 70067) (90% ee), the fungusCunninghamella elegans (ATCC 26269) (94% ee), as well as the cyanobacteriumSynechococcus leopoliensis (94% ee). From the green algae tested,Chlamydomonas reinhardii showed the highest enantioselectivity (85% ee). 相似文献
2.
O. Verona 《Mycopathologia》1962,17(4):345-350
Riassunto Sono presentate e descritte sezioni sottili diTrigonopsis variabilis con riferimento alla parete cellulare, alla membrana citoplasmatica, alle cicatrici di gemmazione, al nucleo e ai mitocondri.
Summary Here are presented and described ultrathin sections ofTrigonopsis variabilis, with special regard to the cell wall, to cytoplasmatic membrane, to budding scars and to the nucleus and mitochondria.相似文献
3.
Summary A process was developed for the production ofTrigonopsis variabilis and D-amino acid oxidase. Yields for the yeast were in excess of 220 g/l wet weight and 62 g/l dry weight. Using cephalosporin C as a substrate the enzyme concentration was 7000 units per liter. 相似文献
4.
Summary D-Amino acid oxidase (DAAO) genes were amplified from Trigonopsis variabilis and Rhodotorula gracilis by polymerase chain reactions. T. variabilis DAAO gene was cloned into a pUC19 vector. The expression of the T. variabilis DAAO was directly determined in permeabilized E. coli cells using a micro pO2 probe. The micro pO2 probe was sensitive enough to be suitable for a simple and rapid estimation of DAAO activity toward cephalosporin C. 相似文献
5.
Christian Trampitsch Anita Slavica Waander Riethorst Bernd Nidetzky 《Journal of Molecular Catalysis .B, Enzymatic》2005,32(5-6):271-278
2,6-Dichloroindophenol (DCIP) is shown to be utilised efficiently as electron acceptor replacing dioxygen in the reaction of Trigonopsis variabilis d-amino acid oxidase (TvDAO) with d-methionine as the substrate. The specificity constant for DCIP reduction at 30 °C is one-twelfth that of oxygen conversion into hydrogen peroxide. Time course analysis of simultaneous consumption of DCIP and dioxygen, recorded on-line by absorption and non-invasive fluorescence quenching, respectively, pinpoints the preferential utilisation of dioxygen; and reveals a maximum DCIP conversion rate that is independent of the initial concentration of dioxygen. A robust direct assay of TvDAO activity has been developed that does not require anaerobic reaction conditions. It was down-scaled to microtitre plate format and overcomes practical limitations of other assays due to the low affinity of TvDAO for dioxygen (Km ≈ 0.7 mmol L−1). 相似文献
6.
7.
Zusammenfassung
Trigonopsis variabilis, bisher erst einmal isoliert (1929), wurde in einem Traubenmost aus dem Weinbaugebiet des Staates S. Paulo, Brasilien, wieder aufgefunden. Es wird sein morphologisches und physiologisches Verhalten unter verschiedenen Kulturbedingungen beschrieben. 相似文献
8.
Background
Immobilization of Trigonopsis variabilis D-amino acid oxidase (TvDAO) on solid support is the key to a reasonably stable performance of this enzyme in the industrial process for the conversion of cephalosporin C as well as in other biocatalytic applications. 相似文献9.
Kurtzman CP 《Antonie van Leeuwenhoek》2007,92(2):221-231
Three new species of Candida and a new species of Trigonopsis are described based on their recognition from phylogenetic analysis of gene sequences from large subunit ribosomal RNA, ITS1/ITS2
rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II. Candida
infanticola sp. nov. (type strain NRRL Y-17858, CBS 7922) was isolated from the ear of an infant in Germany and is closely related to
Candida sorbophila. Candida polysorbophila sp. nov. (type strain NRRL Y-27161, CBS 7317) is a member of the Zygoascus clade and was isolated in South Africa as a contaminant from an emulsion of white oil and polysorbate. Candida transvaalensis sp. nov. (type strain NRRL Y-27140, CBS 6663) was obtained from forest litter, the Transvaal, South Africa, and forms an
isolated clade with Candida santjacobensis. Trigonopsis californica sp. nov. (type strain NRRL Y-27307, CBS 10351) represents a contaminant from wine in California, and forms a well-supported
clade with Trigonopsis cantarellii, Trigonopsis variabilis and Trigonopsis vinaria. 相似文献
10.
Several fungal species namely: Aspergillus niger, Aspergillus parasiticus, Penicillium funiculosum, Trigonopsis variabilis and two different strains of Fusarium oxysporum were tested toward racemic mixtures of following phosphonic acids: 1-amino-2-methylpropanephosphonic acid, 1-aminophenylmethanephosphonic acid and 1-amino-2-phenylethanephosphonic acid. Application of F. oxysporum strain (UW1) allowed obtaining optically pure S-isomer of 1-aminophenylmethanephosphonic acid and R-isomer of 1-amino-2-phenylethanephosphonic acid, whereas biotransformation of racemic mixture of 1-amino-2-methylpropanephosphonic acid with F. oxysporum strain (DSM 12646) cells resulted in obtaining pure enantiomer of R-configuration. 相似文献
11.
Effect of Mineral Phosphate Solubilization on Biological Nitrogen Fixation by Diazotrophic Cyanobacteria 总被引:4,自引:0,他引:4
The ability of two diazotrophic cyanobacteria Westiellopsis prolifica and Anabaena variabilis were examined to solubilize extracellular insoluble tricalcium phosphate (TCP) and Mussorie rock phosphate (MRP). The two
strains exhibited a differential response to insoluble forms of phosphorus used. W. prolifica showed better growth in presence of MRP while A. variabilis proliferated better in presence of TCP. Biological nitrogen fixation measured in terms of acetylene reduction (AR) activity
showed significant variation among the concentrations of TCP or MRP and time of incubation. W. prolifica and A. variabilis showed maximum AR activity on 14 and 21 days of incubation respectively. In general AR activity in presence of MRP was always
less than that in presence of TCP at all concentrations. Among the two cyanobacteria A. variabilis was best in terms of P-solubilization and nitrogen fixation and TCP (20 mg P l−1) was the best source of insoluble P rather than MRP or K2HPO4. 相似文献
12.
Production of D-amino acid oxidase, L-aromatic aminotransferase and aromatic lactate dehydrogenase by several yeast species was examined. Of 16 strains tested, Trigonopsis variabilis and Rhodosporidium toruloides were found to be most suitable for D-amino acid oxidase production, T. variabilis and Brettanomyces anomalus for L-aromatic aminotransferase production, and Hansenula polymorpha, Cryptococcus terreus, and Candida maltosa for aromatic lactate dehydrogenase production. This selection is based on a high amount of enzyme activity as well as a broad enzyme specificity. The data will be reported here. 相似文献
13.
《Biocatalysis and Biotransformation》2013,31(2-3):227-235
Kinetic aspects of the bacterial reduction of hexavalent chromium (chromate: CrO2-4) were investigated using Enterobacter cloacae strain HO1. E. cloacae strain HO1 could reduce hexavalent chromium to the trivalent form (Cr3+) anaerobically. High concentrations of CrO2-4 inhibited the reduction, and a substrate inhibition model gave a good fit to the observed data. The rate of chromate reduction was proportional to cell density. The effect of temperature on the reduction rate followed the Arrhenius equation. The rate of chromate reduction was also dependent on pH and the concentrations of carbon and energy sources in the culutre medium. Amino acids including asparagine, methionine, serine and threonine were utilized effectively as carbon and energy sources for chromate reduction. 相似文献
14.
C. J. Crossland 《Coral reefs (Online)》1987,6(1):35-42
Rates of mucus and DOC-lipid release were determined for colonies of Acropora variabilis and Stylophora pistillata at 5 m depth and for a colony of A. variabilis at 23 m depth. In addition, colonies at 5 m were shaded to simulate ambient irradiance at 6 m, 10 m and 16 m depth to evaluate the effect of light on the rates of release. A. variabilis released more mucus and DOC-lipid at 5 m than at 23 m depth. For both corals, the night rates were about 30% those of the day. A reduction in total integrated irradiance decreased mucus output from the corals. Similarly, DOC-lipid release showed a diurnal pattern and diminished with reduction in daily irradiance. For both coral species, DOC-lipid release rates were greater in the afternoon than in the morning. The night rates were less than 55% those of the day. The DOC-lipid comprised wax esters and a phospholipid fraction. The diurnal variation was due to changes in yield of wax esters which contributed >90% of the carbon released as DOC-lipid. In situ release of mucus and DOC-lipid was infuenced by light effects on phototrophic carbon metabolism. A daily budget for carbon released as mucus and DOC-lipid was estimated for each coral species at 5 m depth. 相似文献
15.
Parshina SN Kijlstra S Henstra AM Sipma J Plugge CM Stams AJ 《Applied microbiology and biotechnology》2005,68(3):390-396
Biological sulfate (SO4) reduction with carbon monoxide (CO) as electron donor was investigated. Four thermophilic SO4-reducing bacteria, Desulfotomaculum thermoacetoxidans (DSM 5813), Thermodesulfovibrio yellowstonii (ATCC 51303), Desulfotomaculum kuznetsovii (DSM 6115; VKM B-1805), and Desulfotomaculum thermobenzoicum subsp. thermosyntrophicum (DSM 14055), were studied in pure culture and in co-culture with the thermophilic carboxydotrophic bacterium Carboxydothermus hydrogenoformans (DSM 6008). D. thermoacetoxidans and T. yellowstonii were extremely sensitive to CO: their growth on pyruvate was completely inhibited at CO concentrations above 2% in the gas phase. D. kuznetsovii and D. thermobenzoicum subsp. thermosyntrophicum were less sensitive to CO. In pure culture, D. kuznetsovii and D. thermobenzoicum subsp. thermosyntrophicum were able to grow on CO as the only electron donor and, in particular in the presence of hydrogen/carbon dioxide, at CO concentrations as high as 50–70%. The latter SO4 reducers coupled CO oxidation to SO4 reduction, but a large part of the CO was converted to acetate. In co-culture with C. hydrogenoformans, D. kuznetsovii and D. thermobenzoicum subsp. thermosyntrophicum could even grow with 100% CO (PCO=120 kPa). 相似文献
16.
A method for isolation of d-amino acid oxidase (DAAO) from disrupted Trigonopsis variabilis cells has been developed. In an aqueous two-phase system consisting of PEG6000 (220 g l–1), potassium phosphate (110 g l–1, K2HPO4 + KH2PO4 = 10.1:1, mol mol–1) and dl-methionine (11 g l–1), the major portion of cellular proteins (87%) was partitioned into the salt phase. By sequential extraction, 48% of DAAO was recovered in PEG phase, giving a yield of 211 U mg protein–1. 相似文献
17.
To convert cephalosporin C to 7-aminocephalosporin (7-ACA), a D-amino acid oxidase (DAAO) gene from Trigonopsis variabilis and a glutaryl-7-aminocephalosporanic acid acylase (GL-7-ACA acylase) gene from Pseudomonas were cloned and expressed in recombinant Escherichia coli. For DAAO recombinant strain BL21(DE3)/pET-DAAO, a high DAAO activity of 250 U ml−1 was obtained by a fed-batch culture. A GL-7-ACA acylase gene, in which the signal peptide sequence was deleted, was also successfully expressed in a recombinant E. coli BL21(DE3)/pET-ACY with a high expression level of 3000 U l−1. A novel recombinant strain, BL21(DE3)/pET-DA, harboring both genes of DAAO and GL-7-ACA acylase, was further constructed, and a rather high DAAO activity of 140 U ml−1 and GL-7-ACA acylase activity of 950 U l−1 were simultaneously obtained. This recombinant strain, in which two genes are co-expressed, made it possible to catalyze cephalosporin C into 7-ACA directly. 相似文献
18.
Effective recombinant strains Pichia pastoris that produce functionally active hybrid of Trigonopsis variabilis D-aminoacids bond with chitin-connecting domain of chitinase A1 of Bacillus circulans (DAOcbd) were obtained. The dependence of DAOcbd production levels from production of the number of copies of “expression
cassette” integrated in the AOX1 locus of recombinant strains was studied. It was indicated that synthesized DAOcbd may be
easily purified and immobilized on chitin sorbents and possessed high specific activity. Produced strains and methods of their
cultivation and DAOcbd extraction may be used for development of technologies of obtaining of biocatalyzers in technological
processes of obtaining of 7-aminocepha-losporane acid. 相似文献
19.
Double d-amino acid oxidases (dRtDAO and dTvDAO) were previously genetically constructed by linking the C-terminus of one subunit
of their corresponding native DAOs from Rhodosporidium toruloides and Trigonopsis variabilis (RtDAO and TvDAO) to the N-terminus of the other identical subunit. We have now immobilized these double DAOs and their native
counterparts onto streptavidin-coated magnetic beads through the interaction between biotin and streptavidin. The catalytic
efficiencies (kcat/KM) of immobilized DAOs toward d-alanine and cepharosporin C remained similar to those of their soluble forms, except the catalytic efficiency of immobilized
TvDAO toward d-alanine was decreased by 56%. After immobilization, the Tm value for RtDAO was shifted 15°C higher to 60°C, while those for dRtDAO, TvDAO and dTvDAO were increased by 5–8°C to 56,
60 and 60°C, respectively. In the presence of 10 mM H2O2, immobilized RtDAO, dRtDAO, TvDAO and dTvDAO exhibited half-lives of about 8, 10, 3 and 5 h, respectively, giving 16-, 10-,
6- and 7-fold greater stability than their soluble forms, respectively. Therefore, immobilization through biotin–streptavidin
affinity binding enhances the thermal and oxidative stability of native and double DAOs studied, especially RtDAO. The additive
stabilizing effect of subunit fusion and immobilization was more pronounced in the case of RtDAO than TvDAO. 相似文献
20.
Leticia Pizzul María del Pilar Castillo John Stenström 《World journal of microbiology & biotechnology》2006,22(7):745-752
Summary Five strains of the Rhodococcus and Gordonia genera were evaluated for their potential use in bioremediation of polycyclic aromatic hydrocarbons (PAH) with or without
another substrate (co-substrate). Their ability to produce biosurfactants or to degrade phenanthrene when growing on glucose,
hexadecane and rapeseed oil was tested in liquid medium at 30 °C. All strains showed biosurfactant activity. The highest reduction
in surface tension was recorded in whole cultures of Rhodococcus sp. DSM 44126 (23.1%) and R. erythropolis DSM 1069 (21.1%) grown on hexadecane and Gordonia sp. APB (20.4%) and R. erythropolis TA57 (18.2%) grown on rapeseed oil. Cultures of Gordonia sp. APB and G. rubripertincta formed emulsions when grown on rapeseed oil. After 14 days of incubation, Rhodococcus sp. DSM 44126 degraded phenanthrene (initial concentration 100 μg ml−1) as sole carbon source (79.4%) and in the presence of hexadecane (80.6%), rapeseed oil (96.8%) and glucose (below the limit
of detection). The other strains degraded less than 20%, and then with a co-substrate only. Rhodococcus sp. DSM 44126 was selected and its performance evaluated in soil spiked with a mixture of PAH (200 mg kg−1). The effect of the addition of 0, 0.1 and 1% rapeseed oil as co-substrate was also tested. Inoculation enhanced the degradation
of phenanthrene (55.7% and 95.2% with 0.1% oil and without oil respectively) and of anthracene (29.2% with 0.1% oil). Approximately
96% of anthracene and 62% of benzo(a)pyrene disappeared from the soil (inoculated and control) after 14 days and anthraquinone was detected as a metabolite. Rhodococcus sp. DSM 44126 was identified as Rhodococcus wratislaviensis by 16S rRNA sequencing and was able to degrade anthracene as sole carbon source in liquid culture. 相似文献