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1.
A comparison of the rate of carboxymethyl cellulase (CMCase), avicelase, xylanase, -glucosidase and -xylosidase production and rates of growth by 4 different strains ofCellulomonas revealed a wide range of behaviour; with some strains producing more CMCase, avicelase, xylanase, -glucosidase and -xylosidase from complex lignocellulosic (LC) biomass (from saline land) and CMC while some others producing small amounts of these enzymes. One strain,C. biazotea, was better with respect to enzyme production potential and growth behaviour than most of the other strains and has been chosen as a starting strain for genetic improvement for producing enzymes of the cellulase complex.  相似文献   

2.
Penicillium purpurogenum was mutated with u.v. light to increase xylanase production. The best mutant, UV-64, was treated with N-methyl-N'-nitro-N-nitrosoguanidine and a second generation of mutants was obtained (NG-188 and NG-737). NG-737 produced 125 U of xylanase/ml when grown on oat spelts xylan supplemented with wheat bran compared with 69 U/ml for the wild-type strain. The mutants also showed a 2.2-fold increase in -xylosidase as compared with the wild-type.  相似文献   

3.
Direct inhibitory effects of bacillus Calmette-Guérin (BCG) and interferon 2b (IFN2b) on six human bladder carcinoma cell lines, UCRU-BL-13, UCRU-BL-17, UCRU-BL-28, 5637, T24 and J82, were studied using an in vitro proliferation assay. Effects on proliferation following exposure to BCG or IFN2b were analysed by [3H]thymidine incorporation over 7 days. BCG had an antiproliferative effect on all bladder lines, while sensitivity to IFN2b varied greatly, being as remarkably low as 1 U/ml for some lines. The antiproliferative effect was greatest when cells were exposed continuously to either agent, but was still evident with a limited exposure. When clinical concentrations were simulated in vitro, BCG+IFN2b was more effective than BCG alone and as effective as a double BCG concentration. We conclude that, in addition to their immunomodulatory effects, BCG and IFN2b directly inhibit the proliferation of human bladder cancer cells, and often at extremely low concentrations.  相似文献   

4.
The conformational properties of the oligosaccharide chain of GM1 ganglioside containingN-glycolyl-neuraminic acid, -Gal-(1-3)--GalNAc-(1-4)-[-Neu5Gc-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer, were studied through NMR nuclear Overhauser effect investigations on the monomeric ganglioside in dimethylsulfoxide, and on mixed micelles of ganglioside and dodecylphosphocholine in water. Several interresidual contacts for the trisaccharide core--GalNAc-(1-4)-[-Neu5Gc-(2-3)]--Gal-were found to fix the relative orientitation of the three saccharides, while the glycosidic linkage of the terminal -Gal-was found to be quite mobile as the -Gal-(1-3)--GalNAc-disaccharide exists in different conformations. These results are similar to those found for two GM1 gangliosides containingN-acetyl-neuraminic acid and neuraminic acid [1].Abbreviations Ganglioside nomenclature is in accordance with Svennerholm [23] and the IUPAC-IUB Recommendations [24] GM3(Neu5Ac) II3Neu5AcLacCer, -Neu5Ac-(2-3)--Gal-(1-4)--Glc-(1-1)-Cer - GM3(Neu5Gc) II3Neu5GcLacCer, -Neu5Gc-(2-3)--Gal-(1-4)--Glc-(1-1)-Cer - GM1(Neu5Ac) II3Neu5AcGgOse4Cer, -Gal-(1-3)--GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - GM1(Neu5Gc) II3Neu5GcGgOse4Cer, -Gal-(1-3)--GalNAc-(1-4)-[-Neu5Gc-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - GM1(Neu) II3NeuGgOse4Cer, -Gal-(1-3)--GalNAc-(1-4)-[-Neu-(2-3)]--Glc-(1-1)-Cer - GD1a IV3Neu5AcII3Neu5AcGgOse4Cer, -Neu5Ac-(2-3)--Gal-(1-3)--GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - GalNAc-GD1a IV4GalNAcIV3Neu5AcII3Neu5AcGgOse4Cer, -GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-3)--GalNAc-(1-4)-[-Neu5Ac-(2-3)]--Gal-(1-4)--Glc-(1-1)-Cer - Neu neuraminic acid - Neu5Ac N-acetyl-neuraminic acid - Neu5Gc N-glycolyl-neuraminic acid - Cer ceramide  相似文献   

5.
Mattres  Dieter 《Zoomorphology》1962,51(4):375-546
Ohne ZusammenfassungAlphabetisches Verzeichnis der im Text gebranchten Abkürzungen AK Anbieten der Kopfgrube () - AR-seitig außenrandseitig (auf Elytre bezogen) - EO Elytralorgan (EO-Arten = Arten mit Elytralorganen im männlichen Geschlecht) - f Flucht () - F Flucht () - FA, fa frontale Auseinandersetzung (, ) - FS, fs Fühlertrillern bzw. Frontalspiel (, ) - gk Grubenknabbern () - IR-seitig innenrandseitig (auf Elytre bezogen) - K Kopulation - KG Kopfgrube (KG-Arten = Arten mit Kopfgrube im männlichen Geschlecht) - KI Abdomenkitzeln () - KV Kopulationsversuch () - LP-Feld den weiblichen Labialpalpen korreliertes Drüsenporenfeld - MP-Feld den weiblichen Maxillarpalpen korreliertes Drüsenporenfeld - 180 Drehung des um 180° - ob Organbeißen () - ok Organknabbern () - OZ Organzuwendung () - P Prüfung der Kopulationsbereitschaft durch - RB rückwärtige Berührung durch - SLV Seitwärtslauf nach vorn () - SLH Seitwärtslauf nach hinten () - U Umrundung () - vl Vorwärtslauf () - 180 Drehung des um 180° Habilitationsschrift.  相似文献   

6.
Summary Organic pyrophosphates such as UppA and NAD are formed when a solution containing a nucleotide, a nucleoside 5-polyphosphate, Mg2+ and imidazole are allowed to dry out. We suggest that this synthesis may have occured concurrently with oligonucleotide formation.Abbreviations Im Imidazole - CDI 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride - EDTA ethylenediaminetetraacetic acid - A adenosine - U uridine - pnA adenosine 5-poly-phosphate containing n phosphate residues - pU uridine 5-phosphate - AppA P1,P2-diadenosine 5-pyrophosphate - UppA P1-(uridine 5)-P2-(adenosine 5)-pyrophosphate - ImpA adenosine 5-phosphorimidazolide - NMN nicotinamide mononucleotide - NAD nicotinamide-adenine dinucleotide  相似文献   

7.
Cryopreservation of callus tissue of Artimisia annua L. was optimized. Two lines of calli were precultured on MS medium with 5% (v/v) dimethyl sulfoxide, and protected by a cryoprotectant containing 15% (v/v) ethylene glycol, 15% (v/v) dimethyl sulfoxide, 30% (v/v) glycerol and 13.6% (w/v) sucrose. The highest survival rate of callus A201 reached 87% after it was pretreated at 25°C, cryopreserved by liquid nitrogen, recovered in water bath at 25°C and reloaded at 25°C with 34% (w/v) sucrose solution, and that of callus A202 reached 78% after it was treated as callus A201, except pretreated at 35°C, recovered at 35°C and reloaded with 47.8% (w/v) sucrose solution.  相似文献   

8.
The ligninolytic white-rot fungus Phanerochaete chrysosporium BKM-F-1767 produced extracellular cellulolytic enzymes (carboxymethylcellulase, CMCase and -glucosidase) and xylanolytic enzymes (xylanase and -xylosidase) in liquid medium containing 1.0% sugarcane bagasse with or without 1.0% glucose. The changes in pH and soluble protein content were monitored in the culture filtrates. The results obtained showed that the pH decreased after 3 days and then increased. The soluble protein content increased and reached the maximum value after 12 days. The results showed that the activities of enzymes were higher in the case of sugarcane bagasse without glucose. The characterization study indicated that the optimum pH values were 4.6, 4.2, 5.0 and 5.0 for CMCase, -glucosidase, xylanase and -xylosidase, respectively and the optimum temperatures were 60, 70, 65 and 60 °C for the investigated enzymes, respectively. The results showed also that after prolonged heating (5 h) at 60 °C, CMCase, -glucosidase, xylanase and -xylosidase retained 81.2, 86.8, 51.5 and 27.4% activity, respectively.  相似文献   

9.
Summary The influence of unbalanced mating systems — factorial mating (FM) and random loss of families after a full diallel crossing (RS) — on the ultimate probability of gene fixation (u()) and the time required to fix or lose a gene (t()) are investigated. The average u() of these systems is smaller than that of random mating, and the range of u() for a given initial parental genotype combination is very large (close to one for most initial genotypic combinations). The average u() of different parental genotypic combinations of a given gene frequency are different. These systems accelerate the t().This article was written and prepared by U.S. Government employees on official time, and it is therefore in the public domain  相似文献   

10.
The inheritance of host plant resistance and its effect on the relative infection efficiency for leaf blast was studied in the crosses IR36/CO39 (partially resistant × highly susceptible) and IR36/IR64 (both partially resistant). On the natural scale, gene action appeared multiplicative. After log transformation, additive effects described most of the genetic variation in the cross IR36/CO39, while additive and dominance effects were about equal in magnitude in the cross IR36/IR64. Dominance was towards increased resistance. No transgressive segregation occurred in the cross IR36/CO39. The number of genes that reduce lesion number was estimated to be zero in CO39 and five or more in IR36. The cross IR36/IR64 showed transgressive segregation in both directions, and IR36 and IR64 each contain at least one gene that is not present in the other cultivar. The heritabilities (narrow sense) in the F2 were low (range 0.06–0.16), while narrow sense heritabilities based on F3 lines were much higher (range 0.41–0.68). Lesion numbers in F3 lines were reasonably correlated with those in F5 progenies derived from the same F2 plant (r was±0.6 in both crosses). Partial resistance can be effectively improved by selecting the most resistant plants from the most resistant F3 lines.  相似文献   

11.
F. Liners  P. Van Cutsem 《Protoplasma》1992,170(1-2):10-21
Summary A monoclonal antibody (2 F 4) recognizing a conformational epitope of polygalacturonic acid was used for immunogold localization of pectins in walls of suspension-cultured carrot (D. carota L.) cells at the electron microscopic level. In microcolonies of young or mature cells, polygalacturonic acid was essentially located on the middle lamella material expanded at three-way junctions between cells or lining intercellular spaces but was not found in primary walls. Middle lamellae far from junction zones and intercellular spaces were not recognized. Largely esterified pectic polymers, only detected by the 2 F 4 antibodies after on-grid de-esterification treatment by pectin methyl esterases, were present within all primary cell walls. Golgi bodies and associated vesicles were also labeled by the 2 F 4 antibodies only after de-esterification treatment, which indicates that pectic polymers are synthesized and secreted in a highly esterified form. A decrease of pectin esterification, which results probably from an in situ enzymatic de-esterification of the pectic polymers of the primary walls, was observed in senescent cells. These results are discussed in relation to biochemical analyses showing changes of the methyl ester content of pectins during the cell-wall growth.  相似文献   

12.
In liquid synthetic medium inoculated with Sclerotium rolfsii (SR), addition of 6-methylpurine (MP, 50g/ml) immediately after inoculation led to approximately 100% reduction in sclerotia production. Adenosine, and to a lesser extent guanosine, each at final concentration of 100g/ml significantly reduced inhibition of sclerotia formation by SR in presence of 50g/ml MP. Uridine and cytidine each at 100g/ml had no such effect. The inhibition of sclerotia morphogenesis could be prevented by addition of 800g/ml of adenosine together with 50g/ml MP. Reversal by adenosine of MP-induced inhibition of sclerotia development was concentration dependent.  相似文献   

13.
The relationship of abscisic acid (ABA) and 2-trans-abscisic acid (t-ABA) to alternate bearing has been examined in Wilking mandarin (Citrus reticulata Blanco) trees. Leaves, stems and buds of trees loaded with fruit (on trees) had 4.3, 6.0 and 2.2 fold higher ABA levels than the corresponding organs from off trees. Leaves had higher ABA levels than stems and buds in both on and off trees. t-ABA was non-detectable in Wilking leaf, stem and bud tissue. Amounts of t-ABA not exceeding 40% of the ABA content, were found in Shamouti and Valencia orange buds and in Wilking fruit peel.The elevated levels of ABA in on tree organs may reflect a stress imposed by the fruit overload.  相似文献   

14.
A thermotolerant fungal strainAspergillus terreus produced high activities of cellulolytic enzymes when grown in shake flasks for 8 days at 40°C or 14 days at 28°C in medium containing 2.5% (w/v) cellulose powder and 1% (w/v) wheat bran. There was little difference between the final activities of endo-(1,4)--glucanase (ca. 14.4 U/ml); filter paper activity (ca. 1.3 U/ml) and -glucosidase (ca. 10 U/ml). Endoglucanase had maximum activity at 60°C and pH 3.8; the other two enzymes were optimal at 60°C and pH 4.8. The maximum hydrolysis of different cellulosic substrates (about 50%) was obtained within 48 h when 1.1 U/ml of filter paper cellulase activity were employed to saccharify 100 mg alkali-treated cotton, filter paper, bagasse, and rice straw at 50°C and pH 4.8. The major end-product, glucose, was produced from all substrates, with traces of cellobiose and other larger oligosaccharides being present in rice straw hydrolysates.  相似文献   

15.
We report on the habitat dependent invasion and control pattern of the English cordgrass, Spartina anglica C. E. Hubbard, in Puget Sound, Washington. In 36 years, the plant has successfully invaded 73 sites, affecting 3311 ha of marine intertidal habitat, which if allowed to solidly fill, would equal 400ha. Invasion and control both depend on habitat type. Mudflats and low salinity marshes have significantly more solid area of S. anglica than do high salinity marshes and cobble beaches. Control efforts since 1997 have resulted in a 13% decline of the grass. We find that high salinity marshes have the greatest decline ( 70%), low salinity marshes have the lowest decline ( 10%), and mudflat ( 29%) and cobble beaches ( 21%) have intermediate losses. We hypothesize that invasion success and control are dependent on a relatively complex interplay between habitat physical conditions and species interactions.  相似文献   

16.
The complete definition of the chemical structure of GD1b-ganglioside (GD1b) lactone isolated from human brain has been given by means of spectrometric and spectroscopic analyses. GD1h lactone contains a single ester linkage involving the external sialic acid carboxyl group and the C-9 hydroxyl group of the internal sialic acid unit. A synthetic lactone of GD1b prepared treating GD1b with glacial acetic acid characterized in the same way showed an identical chemical structure.Abbreviations: Ganglioside nomenclature is according to Svennerholm [16] and the IUPAC-IUB Recommendations [17] GM1 GM1-ganglioside, II3NeuAc-GgOse4Cer, Gal1-3GalNac1-4[NeuAc2-3]Gal1-4Glc1-1Cer - GD1b GD1b-ganglioside, II3(NeuAc)2GgOse4Cer, Gal1-3GalNAc1-4[NeuAc2-8NeuAc2-3]Gal1-4Glc1-1Cer - GD1b lactone GD1b-L, Gal1-3GalNAc1-4[NeuAc(1-9)2-8NeuAc2-3]Gal1-4Glc1-1Cer - Cer ceramide - FAB-MS fast atom bombardment-mass spectrometry - 1H-NMR proteon nuclear magnetic resonance - 1D-NMR one dimensional NMR - 2D-COSY two dimensional correlated spectroscopy - DMSO-d6 deuterated dimethylsulfoxide  相似文献   

17.
Maximum inhibition of Glycine max, cv. Essex seed germination occurred at 10 g/ml following 72 hr imbibition in constant light. Seeds imbided 108 hr in constant darkness at this concentration showed a 20% rise in germination over that of the control. Imbibition of G. max, cv. Williams seeds in either light or dark for 96 hr did not suppress germination. Imbibition of Essex seeds in either light or dark at 2.5 through 10 g/ml stimulated root elongation except for 10 g/ml at 96 hr (light). Maximum inhibition of Williams root elongation under constant light was at 48 and 72 hr with 10 g/ml. Statistically significant differences in cotyledon, leaf and stem lengths between non-treated (NT) and treated (T) seedlings were not found except for Williams stem length at 2.5 / ml. Root elongation was stimulated 1.2- and 1.1-folds, respectively, at 5.0 (Essex) and 2.5 (Williams) g/ml. Toxin at 2.5 through 10.0 g/ml did not markedly alter either cotyledon or leaf widths with the exception of Williams leaf width at 2.5 g/ml. Medium supplementation with 2.5 through 10.0 g/ml resulted in cotyledon, leaf and root weight enhancements for Essex seedlings. Stem weight was not markedly affected. An 18% rise in Williams cotyledon weight above that of the control was seen at 2.5 g/ml. Williams leaf weights were increased 1.75- and 1.25-folds, respectively, at 2.5 and 10.0 g/ml. Aflatoxin B1, at 2.5 g/ml promoted Williams stem and root elongation 1.20- and 1.09-folds, respectively. Most of the radioactivity from 65Zn-ZnCl2 recovered within organs was found within Essex roots for both T and NT seedlings. A higher amount of radioactivity was recovered within roots at each toxin concentration than was without toxin. However, this was not statistically significant. Significant differences in the distribution of radioactivity within roots between NT and T Williams seedlings were not observed. Generally, AFB1 failed to affect significantly these two varieties of soybeans based on the tests relating to germination, growth and radiolabel uptake.  相似文献   

18.
Summary In the progeny of a hybrid between monotelosomic line 3B of Chinese Spring wheat and Chinese Spring — Aegilops longissima ditelosomic addition line G a cytologically stable strain was selected consisting of 20 wheat chromosome pairs, one pair of telosomic chromosome 3BL and one pair of telosomic longissima chromosome G. Inoculating Chinese Spring — Aegilops longissima addition and substitution lines with ten different powdery mildew isolates, partial resistance was observed. The infection grade as well as the number of spores/cm2 leaf area were significantly reduced.  相似文献   

19.
Water relations were analysed in a semi-deciduous forest grove occurring in the oxisols of the Orinoco savannas. This grove has a shallow unconsolidated ironstone cuirass, which is overlaid by a sandy loam layer (0.0–0.5 m) that contains more than 90% of the grove forest root phytomass. Evapotranspiration and through drainage were calculated by using data from the soil profile as related to physical characteristics of the site root zone, hydraulic conductivity, volumetric water content and potential hydraulic gradient. Mean annual evapotranspiration was 783 mm year–1 and annual through drainage below the root zone was 14% (162 mm year–1) of the gross rainfall. This drainage recharged the 42% of the annual saturation deficit of the water table. Similar mean annual evapotranspiration (770 mm year–1) was also calculated by using the water balance components. The mean daily coupling omega factor () between the grove canopy and the surrounding atmosphere indicated that a high degree of coupling (=0.14±0.16) occurs in the grove and evapotranspiration was mainly controlled by surface conductance. As the dry season proceeded, the soil saturation deficit () increased rapidly resulting in a threshold surface conductance (0.030–0.005 m s–1) for ranging from 0.05 to 0.10. Hypotheses to explain the omnipresence of perennial species in the wide range of physical conditions in neotropical savannas are discussed.  相似文献   

20.
Glucoamylase production by a thermophilic mold Thermomucor indicae-seudaticae was optimized in solid-state fermentation (SSF) by conventional one variable at a time approach and further statistically using response surface methodology (RSM). Glucoamylase secretion was strongly affected by three variables (moisture ratio, inoculum level and incubation time), and therefore, these three factors were further optimized using response surface methodology. The glucoamylase production in flasks containing wheat bran, under the conditions optimized by RSM, was 455 ± 23 U/g of dry moldy bran (DMB), while the predicted value by a polynomial model was 433.30 U/g DMB. The enzyme titre (455 ± 23 U/g DMB) attained in the validation experiment of this investigation is higher than those reported in the literature. When the large-scale production was attempted in enamel trays, a marginally lower enzyme titres were attained. An overall 1.8-fold increase in glucoamylase production was achieved in SSF due to statistical optimization in comparison with that of one variable at a time approach (250 ± 13 U/g DMB). A 10-fold enhancement in glucoamylase production was recorded in SSF as compared to that in submerged fermentation.  相似文献   

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