De novo synthesis of fructooligosaccharides in leaf disks of certain Asteraceae. II. Certain physiological and biochemical changes accompanying fructooligosaccharide formation

De novo synthesis of fructosans in leaf disks of certain Asteraceae incubated on phosphate-buffered 5% sucrose medium was accompanied by increases in fresh and dry weight and a considerable enhancement in the rate of respiration. Radiorespirometry using 14C-sucrose showed that the respiratory pool was kept at the expense of both exogenous and endogenous substrates. During the initial 24 h of incubation, about 80% or more of the total respiratory carbon was derived from the exogenously supplied sugar. This proportion gradually decreased during the last 48 h to a final value of about 50%. Of the total sugar taken up by the leaf disks, less than 20% was utilized in respiration while more than four-fifths was available for further metabolism including fructosan formation. The respiratory quotient values remained relatively unchanged from 0.8 to 0.9 throughout most of the incubation period and suggested that endogenous substrate other than carbohydrate was drawn into respiratory metabolism.

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The mechanism of de novo synthesis of fructooligosaccharides in leaf disks of certain Asteraceae. III.

Canadian Journal of Botany ◽

10.1139/b74-021 ◽

1974 ◽

Vol 52 (1) ◽

pp. 181-188 ◽

Cited By ~ 14

Author(s):

K. R. Chandorkar ◽

F. W. Collins

Keyword(s):

De Novo ◽

Specific Activity ◽

Jerusalem Artichoke ◽

De Novo Synthesis ◽

Jerusalem Artichoke Tuber ◽

Exogenous Substrate ◽

Endogenous Substrate ◽

Leaf Disks ◽

Tracer Experiments

14C-tracer experiments revealed that both endogenous and exogenous substrate was incorporated in the fructosans synthesized in leaf disks during incubation on phosphate-buffered sugar media. At least some of the endogenous substrate was derived from a source which was insoluble in 80% ethanol at the start of the incubation period. Endogenous and exogenous substrates were distributed in the fructosans in a pattern which was qualitatively similar regardless of the type of sugar supplied exogenously. A complex relationship was exhibited between the specific activity of various fructosan oligomers, expressed on a gram basis, and their chain length. However, expressed on a molar basis, the specific activity of the fructosyl tail portion of each homolog appeared to be linearly related to the number of hexosyl residues that it contained. Such a relationship suggests that enzymes similar to the Jerusalem artichoke tuber transfructosylases are present in leaf disk tissue after 72 h incubation and indeed may function in the de novo synthesis of fructosans in vivo.

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De novo synthesis of fructo-oligosaccharides in leaf disks of certain Asteraceae

Canadian Journal of Botany ◽

10.1139/b72-040 ◽

1972 ◽

Vol 50 (2) ◽

pp. 295-303 ◽

Cited By ~ 19

Author(s):

K. R. Chandorkar ◽

F. W. Collins

Keyword(s):

Chain Length ◽

De Novo ◽

Close Correlation ◽

Acid Synthesis ◽

Degree Of Polymerization ◽

De Novo Synthesis ◽

The Relationship ◽

Leaf Disks

Incubation of leaf disks of certain genera of Asteraceae on phosphate-buffered, 5% sugar solutions resulted in the de novo synthesis of a homologous series of inulin-type fructosans. Fructo-oligosaccharides of degree of polymerization 3 to 21 or 22 were present in dandelion, chicory, lettuce, hawkweed, and sow thistle leaf disks after 72 h, but not in dahlia or sunflower. Synthesis occurred with media containing either fructose, glucose, or sucrose, but not with mannose or galactose. Fructosan formation began after about 36 h and continued with the sequential synthesis of homologs of increasing chain length. After 72 h, the relationship between the amount of polymer synthesized and the chain length appeared to be logarithmically biphasic, consisting of two series of exponentially decreasing values. Incubation for 120 h however, resulted in a distribution more closely resembling that found naturally in fructosan storing tissues. 14C-tracer studies showed that both the endogenous and exogenous carbohydrate sources contribute to fructosan synthesis. Fructo-oligosaccharide formation was blocked by cycloheximide, puromycin, and actinomycin D but not chloramphenicol, indicating that cytoplasmic protein and nucleic acid synthesis was required. Analysis of fructosan formation during incubation suggests a close correlation between transfructosylation mechanisms observed in vitro and the de novo synthesis of fructosans in vivo.

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Brominated Secondary Compounds from the Marine Sponge Verongia aerophoba and the Sponge Feeding Gastropod Tylodina perversa

Zeitschrift für Naturforschung C ◽

10.1515/znc-1993-7-818 ◽

1993 ◽

Vol 48 (7-8) ◽

pp. 640-644 ◽

Cited By ~ 31

Author(s):

Ratana Teeyapant ◽

Patricia Kreis ◽

Victor Wray ◽

Ludger Witte ◽

Peter Proksch

Keyword(s):

Chemical Analysis ◽

Marine Sponge ◽

De Novo ◽

Dry Weight ◽

Secondary Compounds ◽

Yellow Pigment ◽

De Novo Synthesis ◽

Brominated Compounds ◽

Total Concentrations ◽

Collection Sites

Abstract Analysis of the marine sponge Verongia aerophoba from the Canary islands afforded the brominated secondary constituents isofistularin-3, aerophobin-1 and aerophobin-2 which are probably involved in the chemical defense of the sponge. In addition the yellow pigment uranidine and the unusual sterol aplysterol were isolated. The patterns of brominated compounds were almost superimposable when samples of V. aerophoba from different islands were com pared by HPLC indicating de novo synthesis by the sponge or by endosymbiotic microorganisms rather than uptake by filter feeding. The only differences observed between the different samples analyzed were with regard to the total concentrations of brominated compounds which varied from 7.2-12.3% of the dry weight dependent on the different collection sites. The Opisthobranch gastropod Tylodina perversa is specialized for feeding on V. aerophoba. Chemical analysis of the gastropod revealed the sponge constituents uranidine, isofistularin-3, aerophobin-1 and aerophobin-2 as well as aerothionin, a further brominated compound which is apparently a biotransform ation product of the brominated sponge constiiuents.

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Biocatalytic Potential of Native Basidiomycetes from Colombia for Flavour/Aroma Production

Molecules ◽

10.3390/molecules25184344 ◽

2020 ◽

Vol 25 (18) ◽

pp. 4344

Author(s):

David A. Jaramillo ◽

María J. Méndez ◽

Gabriela Vargas ◽

Elena E. Stashenko ◽

Aída-M. Vasco-Palacios ◽

...

Keyword(s):

De Novo ◽

Dry Weight ◽

Product Yield ◽

De Novo Synthesis ◽

Submerged Cultures ◽

Catalytic Potential ◽

Aroma Production ◽

First Time ◽

Cape Gooseberry ◽

Β Carotene

Aromas and flavours can be produced from fungi by either de novo synthesis or biotransformation processes. Herein, the biocatalytic potential of seven basidiomycete species from Colombia fungal strains isolated as endophytes or basidioma was evaluated. Ganoderma webenarium, Ganoderma chocoense, and Ganoderma stipitatum were the most potent strains capable of decolourizing β,β-carotene as evidence of their potential as biocatalysts for de novo aroma synthesis. Since a species’ biocatalytic potential cannot solely be determined via qualitative screening using β,β-carotene biotransformation processes, we focused on using α-pinene biotransformation with mycelium as a measure of catalytic potential. Here, two strains of Trametes elegans—namely, the endophytic (ET-06) and basidioma (EBB-046) strains—were screened. Herein, T. elegans is reported for the first time as a novel biocatalyst for the oxidation of α-pinene, with a product yield of 2.9 mg of cis-Verbenol per gram of dry weight mycelia used. The EBB-046 strain generated flavour compounds via the biotransformation of a Cape gooseberry medium and de novo synthesis in submerged cultures. Three aroma-producing compounds were identified via GC–MS—namely, methyl-3-methoxy-4H-pyran-4-one, hexahydro-3-(methylpropyl)-pyrrolo[1,2-a]pyrazine-1,4-dione, and hexahydro-3-(methylphenyl)-pyrrolo[1,2-a]pyrazine-1,4-dione.

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Enzymological aspects of de novo synthesis of fructooligosaccharides in leaf disks of certain Asteraceae. IV. The activity of sucrose–sucrose 1-fructosyltransferase

Canadian Journal of Botany ◽

10.1139/b74-178 ◽

1974 ◽

Vol 52 (6) ◽

pp. 1369-1377 ◽

Cited By ~ 18

Author(s):

K. R. Chandorkar ◽

F. W. Collins

Keyword(s):

Crude Protein ◽

De Novo ◽

Gel Filtration ◽

Apparent Molecular Weight ◽

Degree Of Polymerization ◽

Transferase Activity ◽

Protein Extract ◽

Sucrose Medium ◽

Filtration Technique ◽

Leaf Disks

Sucrose–sucrose fructosyltransferase capable of synthesizing the trisaccharide 1F-fructosylsucrose from sucrose was partially purified from crude protein extracts of (1) lettuce leaf disks, which were incubated on a sucrose medium for 72 h, and (2) lettuce leaf midvein–petiole tissue, which normally contains fructosans ranging in degree of polymerization from 3 to about 10–11. Maximum transferase activity was associated with the protein exhibiting an apparent molecular weight of about 100 000 as estimated by gel filtration technique. The transferase was not detected in protein extract of unincubated leaf blade tissue. Evidence presented strongly suggests that the transferase was synthesized de novo in response to incubation of leaf disks on sucrose medium.

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Characterization of Monocyte-Associated Factor V

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649565 ◽

1993 ◽

Vol 70 (02) ◽

pp. 273-280 ◽

Cited By ~ 5

Author(s):

Janos Kappelmayer ◽

Satya P Kunapuli ◽

Edward G Wyshock ◽

Robert W Colman

Keyword(s):

Monoclonal Antibody ◽

Light Chain ◽

Peripheral Blood ◽

De Novo ◽

Factor V ◽

Blood Monocytes ◽

De Novo Synthesis ◽

Hep G2 ◽

Hep G2 Cells ◽

Peripheral Blood Monocytes

SummaryWe demonstrate that in addition to possessing binding sites for intact factor V (FV), unstimulated peripheral blood monocytes also express activated factor V (FVa) on their surfaces. FVa was identified on the monocyte surface by monoclonal antibody B38 recognizing FVa light chain and by human oligoclonal antibodies H1 (to FVa light chain) and H2 (to FVa heavy chain) using immunofluorescence microscopy and flow cytometry. On Western blots, partially cleaved FV could be identified as a 220 kDa band in lysates of monocytes. In addition to surface expression of FVa, monocytes also contain intracellular FV as detected only after permeabilization by Triton X-100 by monoclonal antibody B10 directed specifically to the Cl domain not present in FVa. We sought to determine whether the presence of FV in peripheral blood monocytes is a result of de novo synthesis.Using in situ hybridization, no FV mRNA could be detected in monocytes, while in parallel control studies, factor V mRNA was detectable in Hep G2 cells and CD18 mRNA in monocytes. In addition, using reverse transcriptase and the polymerase chain reaction, no FV mRNA was detected in mononuclear cells or in U937 cells, but mRNA for factor V was present in Hep G2 cells using the same techniques. These data suggest that FV is present in human monocytes, presumably acquired by binding of plasma FV, and that the presence of this critical coagulation factor is not due to de novo synthesis.

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Platelets Stimulate Thromboplastin Synthesis in Human Endothelial Cells

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657323 ◽

1983 ◽

Vol 49 (02) ◽

pp. 069-072 ◽

Cited By ~ 20

Author(s):

U L H Johnsen ◽

T Lyberg ◽

K S Galdal ◽

H Prydz

Keyword(s):

Endothelial Cells ◽

De Novo ◽

Umbilical Vein ◽

Time Dependent ◽

De Novo Synthesis ◽

Human Endothelial Cells ◽

Tumor Promotor ◽

Coagulation Assay ◽

Platelet Aggregates ◽

Umbilical Vein Endothelial Cells

SummaryHuman umbilical vein endothelial cells in culture synthesize thromboplastin upon stimulation with phytohaemagglutinin (PHA) or the tumor promotor 12-O-tetradecanoyl-phorbol-13-acetate (TPA). The thromboplastin activity is further strongly enhanced in a time dependent reaction by the presence of gel-filtered platelets or platelet aggregates. This effect was demonstrable at platelet concentrations lower than those normally found in plasma, it may thus be of pathophysiological relevance. The thromboplastin activity increased with increasing number of platelets added. Cycloheximide inhibited the increase, suggesting that de novo synthesis of the protein component of thromboplastin, apoprotein III, is necessary.When care was taken to remove monocytes no thromboplastin activity and no apoprotein HI antigen could be demonstrated in suspensions of gel-filtered platelets, platelets aggregated with thrombin or homogenized platelets when studied with a coagulation assay and an antibody neutralization technique.

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