ENZYMOLOGISCHE STUDIEN AM ARRHENOBLASTOM

1971 ◽  
Vol 67 (3) ◽  
pp. 577-589 ◽  
Author(s):  
H. Brandau ◽  
L. Brandau
Keyword(s):  
Enzyme Activity ◽  
Citric Acid ◽  
Enzyme Activities ◽  
Citric Acid Cycle ◽  
Hydroxysteroid Dehydrogenase ◽  
Pentose Phosphate ◽  
Testosterone Metabolism ◽  
Acid Cycle ◽  
Enzyme Activity Pattern ◽  
Pentose Phosphate Shunt

ABSTRACT In an arrhenoblastoma of a 24 years old female patient the enzyme activities of the intermediary carbonhydrate metabolism, the citric acid cycle, the glycerophosphate cycle, the pentose-phosphate shunt as well as the steroid-dehydrogenases were measured quantitatively and localized histochemically. The striking high activities of the glycolytic enzymes, the presence of steroid-dehydrogenases and the only moderately increased enzyme activities of the citric acid cycle in comparison with the stroma ovarii identify the arrhenoblastoma as a tissue with steroid hormonal metabolism. High activities of the mentioned enzymes and especially the activities of the steroid-dehydrogenases were localized histochemically only in Leydig-cell-like cells. Therefore these cells may be considered as structures of steroid-biogenesis. The enzyme activity pattern of the steroiddehydrogenases illuminates the biogenetic pathways of androgens. The low activities of the 17β-hydroxysteroid-dehydrogenase in this tissue in comparison with other steroid producing tissues indicate a special testosterone metabolism.

Enzymes of Glucose Metabolism in the Caecum of the Marine Borer Bankia setacea

1970 ◽  
Vol 27 (6) ◽  
pp. 1141-1146 ◽  
Author(s):  
D. L. Liu ◽  
C. C. Walden
Keyword(s):  
Citric Acid ◽  
Glucose Metabolism ◽  
Enzyme Activities ◽  
Citric Acid Cycle ◽  
Acid Cycle ◽  
Modified Embden Meyerhof Pathway

The caecum of the marine borer Bankia setacea was found to contain the enzymes for a modified Embden–Meyerhof pathway, a pentose cycle, and a complete citric acid cycle. The pathways are linked to the digestion of cellulose by the enzyme cellobiase. Significant numbers of bacteria were not detected in the caecum of the borer. Enzyme activities in the citric acid cycle indicate a biosynthesis role for the caecum.

Carbon Isotope Fractionation by Autotrophic Bacteria with Three Different C02 Fixation Pathways

1989 ◽  
Vol 44 (5-6) ◽  
pp. 397-402 ◽  
Author(s):  
Andrea Preuß ◽  
Rolf Schauder ◽  
Georg Fuchs ◽  
Willibald Stichler
Keyword(s):  
Citric Acid ◽  
Carbon Isotope ◽  
Isotope Fractionation ◽  
Citric Acid Cycle ◽  
Pentose Phosphate ◽  
Acetobacterium Woodii ◽  
Acetyl Coa ◽  
Acid Cycle ◽  
Acetyl Coa Pathway ◽  
Cell Carbon

Abstract Carbon isotope fractionation during autotrophic growth o f different bacteria which possess different autotrophic CO2 fixation pathways has been studied. 13C /12C -Ratios in the cell carbon of the following bacteria were determined (CO2 fixation pathway suggested or proven in paren­theses): Alkaligenes eutrophus (reductive pentose phosphate cycle), Desulfobacterium autotrophicum and Acetobacterium woodii (reductive acetyl-CoA pathway), Desulfobacter hydrogenophilus and Thermoproteus neutrophilus (reductive citric acid cycle). The Δδ13C values, which indicate the per mille deviation of the 13C content of cell carbon from that of the CO : used as the sole carbon source, range from - 10%° (reductive citric acid cycle) over - 26%° (reductive pentose phosphate cycle) to -36%° (reductive acetyl-CoA pathway). Acetate formed via the acetyl-CoA pathway by the acetogenic Acetobacterium woodii showed a Δδ13C = -40%°. These data are discussed in view of the different CO2 fixation reactions used by the bacteria and especially with regard to the isotopic composition of sedimentary carbon through time.

Histochemical observations on the distribution of various oxidative and phosphorylative enzymes in larval digeneans parasitizing Bithynia tentaculata (Mollusca: Gastropoda)

Parasitology ◽  
1974 ◽  
Vol 69 (2) ◽  
pp. 137-147 ◽  
Author(s):  
Trevor A. J. Reader
Keyword(s):  
Enzyme Activity ◽  
Citric Acid Cycle ◽  
Histochemical Study ◽  
Pentose Phosphate ◽  
Food Storage ◽  
Gastropod Mollusc ◽  
Acid Cycle ◽  
Bithynia Tentaculata ◽  
Form Part ◽  
Lactate Dehydrogenases

A comparative histochemical study is made on the distribution of succinate dehydrogenases, isocitrate dehydrogenases, malate dehydrogenases, glucose-6-phosphate dehydrogenases, α-glycerophosphate dehydrogenases, alcohol dehydrogenases, lactate dehydrogenases and glycogen phosphorylases in the tissues of sporocysts, rediae, cercariae and metacercariae parasitizing the gastropod mollusc Bithynia tentaculata. The results suggest that metabolic sequences resembling the conventional Embden–Meyerhoff pathway, the Pentose-Phosphate cycle and Krebs’ citric acid cycle may be operational in these larval digeneans. Heaviest enzyme activity is evident in the redial pharynx, the cercarial and metacercarial sucker and in the cercarial tail. Presumably the enzymes giving this heavy reaction form part of the energy producing mechanism for these active organs. Encysted metacercariae show a very heavy enzyme activity when compared with the sporocysts and developing cercariae of the same species. This is presumably associated with the breakdown of food storage materials, particularly glycogen, by these encysted stages.

ZUR LOKALISATION DER INNERSEKRETORISCHEN FUNKTION DES MENSCHLICHEN OVARS

1964 ◽  
Vol 46 (4) ◽  
pp. 580-596 ◽  
Author(s):  
Hartmut Brandau ◽  
Wilfried Luh
Keyword(s):  
Citric Acid ◽  
Enzyme Activities ◽  
Citric Acid Cycle ◽  
Glycolytic Enzymes ◽  
Homogeneous Distribution ◽  
Hormone Production ◽  
Acid Cycle ◽  
Normal Human ◽  
Human Ovaries ◽  
Theca Interna

ABSTRACT The histochemical localization of some oxydative enzymes which catalize steps in the Embden-Meyerhof chain, hexosemonophosphate shunt and the citric acid cycle, was studied in normal human ovaries. In contrast to the very low concentration and homogeneous distribution of enzyme activities of the citric acid cycle in the ovarian components, the theca interna of the developing follicle and the theca and granulosa lutein cells show extremely high levels of activities of TPN-specific and glycolytic enzymes. Attempts were made to establish some relation between the findings mentioned above and the localization of hormone production. It was concluded that the synthesis of progesterone is located in the granulosa lutein cells while the formation of oestrogens takes place in the remaining ovarian components, which show a high activity of TPN-specific and glycolytic enzymes.

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