Effect of wounding on the synthesis of phenols, phenol oxidase, and peroxidase in the tuber tissue of Jerusalem artichoke

1968 ◽  
Vol 46 (11) ◽  
pp. 1339-1343 ◽  
Author(s):  
Marcel Bastin
Keyword(s):  
Phenolic Acids ◽  
De Novo ◽  
Deae Cellulose ◽  
Jerusalem Artichoke ◽  
Phenol Oxidase ◽  
De Novo Synthesis ◽  
Complete Darkness ◽  
Tuber Tissue

Slices of tubers of Jerusalem artichoke were cultured at 28 °C in complete darkness, and the production of phenolic acids, phenol oxidase, and peroxidase was studied in relation to subsequent cutting of the tissue. Wounding increased the production of both phenolic acids and enzymes. Purification of the peroxidase by DEAE-cellulose chromatography showed that not all of its components were synthesized in the injured slices. Cycloheximide and chloramphenicol were added to cultures to investigate a requirement for the de novo synthesis of protein in relation to production of the compounds. Cycloheximide at a concentration of 5 μg/ml strongly inhibited the production of both phenolic acids and the enzymes, but chloramphenicol decreased the production of only phenol oxidase.

scholarly journals Ribonucleic acid polymerase activities in Jerusalem-artichoke tissue

1974 ◽  
Vol 143 (1) ◽  
pp. 107-113 ◽  
Author(s):  
John R. Gore ◽  
John Ingle
Keyword(s):  
Rna Polymerase ◽  
Ribonucleic Acid ◽  
Deae Cellulose ◽  
Jerusalem Artichoke ◽  
Polymerase Activity ◽  
Tuber Tissue ◽  
Rna Polymerase Activity ◽  
Rna Accumulation ◽  
The Relationship

1. Artichoke tuber tissue contained RNA polymerase activity bound to the chromatin and in the supernatant after chromatin sedimentation. 2. The activity in the supernatant, the soluble polymerase, was fractionated into polymerases I and II by DEAE-cellulose chromatography, and the properties of each activity were determined. 3. The proportions of chromatin-bound and soluble activities varied with growth of the tissue, and there was a correlation between chromatin-bound activity and RNA accumulation. 4. The properties of the solubilized chromatin activity were compared with those of the soluble activity, and the relationship between these two activities is discussed.

THE INDUCTION OF NAD KINASE BY DDT IN TRIATOMA INFESTANS

1967 ◽  
Vol 45 (5) ◽  
pp. 619-626 ◽  
Author(s):  
M. Agosin ◽  
Jovita Ilivicky ◽  
S. Litvak
Keyword(s):  
Column Chromatography ◽  
De Novo ◽  
Deae Cellulose ◽  
Triatoma Infestans ◽  
Protective Mechanism ◽  
Nad Kinase ◽  
De Novo Synthesis ◽  
Enzyme Protein ◽  
Sephadex Column ◽  
Immunochemical Techniques

The NAD kinase (EC 2.7.1.23) from Triatoma infestans has been purified and a specific antiserum against it prepared. Immunochemical techniques have shown that the increase in the levels of NAD kinase in nymphs of T. infestans is accompanied by an increase in the amount of enzyme protein. The enzyme is labeled after injection of 14C-labeled leucine in both induced and non-induced insects, but labeling is greater in the former, which further supports the concept that a de novo synthesis of enzyme protein occurs during induction by DDT. The enzyme is heterogeneous by DEAE-cellulose and DEAE-Sephadex column chromatography, but the antiserum does not distinguish this heterogeneity. NAD kinase induction may correspond to a protective mechanism of the insects by increasing the availability of coenzymes required for DDT detoxication.

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

1974 ◽  
Vol 52 (1) ◽  
pp. 181-188 ◽  
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.

De novo Synthesis of Glucose-6-Phosphate- (E.C. 1.1.1.49) and 6-Phosphogluconate Dehydrogenase (E.C. 1.1.1.44) in Plant Storage Tissue Slices

1974 ◽  
Vol 29 (11-12) ◽  
pp. 700-704 ◽  
Author(s):  
Günter Kahl
Keyword(s):  
De Novo ◽  
Pentose Phosphate ◽  
De Novo Synthesis ◽  
Tissue Slices ◽  
Storage Tissue ◽  
Tuber Tissue ◽  
Phosphogluconate Dehydrogenase ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Equilibrium Centrifugation ◽  
Plant Storage

Resting potato tuber tissue possesses only faint activity of the two dehydrogenases of the oxidative pentose phosphate cycle, glucose-6-phosphate- and 6-phosphogluconate dehydrogenase. Slicing of the tissue, however, greatly enhances the action of both enzymes. The slicing-induced increase in activity is a consequence of intensified action of at least 5 glucose-6-phosphate dehydrogenase isozymes and a more differentiated activation/inactivation of seven 6-phosphogluconate dehydrogenase isozymes. Using density labelling and isopycnic equilibrium centrifugation it could be demonstrated, that the bulk of both enzymes appearing after slicing the tissue is the result of de novo synthesis rather than activation of pre-existing proenzymes.

Characterization of Monocyte-Associated Factor V

1993 ◽  
Vol 70 (02) ◽  
pp. 273-280 ◽  
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.

Platelets Stimulate Thromboplastin Synthesis in Human Endothelial Cells

1983 ◽  
Vol 49 (02) ◽  
pp. 069-072 ◽  
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.

DE NOVO SYNTHESIS OF STEROIDS BY THE TESTES OF THE HUMAN FOETUS AT MIDGESTATION

1971 ◽  
Vol 68 (1_Supplb) ◽  
pp. S135 ◽  
Author(s):  
R. S. Mathur ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
De Novo ◽  
De Novo Synthesis ◽  
Human Foetus
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