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PubMed1954

Catalase activity of liver and kidney in frogs with spontaneous renal carcinoma.

The kidney carcinoma of the leopard frog has served for various studies on catalase activity, as a first step in gaining information on enzymatic properties of neoplasms in cold blooded animals. It was found that the activity level of this tumor is reduced to approximately 13 per cent of that of the normal frog's kidney. Systemic effects of the tumor on catalase activity of liver and kidney are evident. Liver catalase in tumor-bearing frogs is diminished to about 50 per cent of the normal, and kidney catalase to an even greater degree; i.e., to about 34 per cent. A positive correlation exists between levels of catalase in tumor and in liver. Frogs kept at 3 different temperatures, 8, 18, and 26.5 degrees C., for upward of 29 days exhibited no significant change in activity levels either of tumor or of livers from normal or from tumor-bearing animals. It is suggested that a seasonal variation may occur in catalase activity of the frog. During the winter months catalase activity of the tumors was found to be higher than during the summer, whereas liver catalase was below the level of normal frogs examined during the summer. Intracoelomic injections of homogenates of tumors promptly lead to diminution of liver catalase lasting for several days. Injection of normal kidney has no such effect. These results with a spontaneous tumor of a cold blooded animal are in essential agreement with the many observations made with transplanted tumors of warm blooded animals. They lend support to the view that neoplasia is a ubiquitous biological process with similar characteristics in all species or classes of vertebrates.

Animals↗
PubMed1955

The alteration of intracellular enzymes. III. The effect of temperature on the kinetics of altered and unaltered yeast catalase.

1. The very large increase in catalase activity (Euler effect) which follows treatment of yeast cells with CHCl(3), UV and n-propanol is accompanied by highly significant changes in kinetic properties. With respect to the enzymatic decomposition of H(2)O(2), the thermodynamic constants of the activation process micro, DeltaHdouble dagger, DeltaSdouble dagger, DeltaFdouble dagger, decrease, following treatment of the intracellular enzyme, by 4.5 kcal., 4.5 kcal., 10.1 e.u. and 1.7 kcal., respectively, all these differences being significant at the 1 per cent level. 2. Similar differences exist between the untreated, intracellular enzyme on the one hand, and the extracted yeast and crystalline beef liver catalases on the other. Significant differences in these thermodynamic constants do not exist among the treated intracellular, extracted yeast, and crystalline liver catalases. 3. These data provide unequivocal confirmation of the phenomenon of enzyme alteration reported previously, and confirm previous evidence that the extracted and crystalline enzymes have also undergone enzyme alteration and have properties which are identical with, or very similar to, those of the catalase altered in situ. 4. With respect to the process of heat destruction of catalase, the greatly diminished stability to heat of the altered enzymes, previously reported, has been confirmed. The thermodynamic constants of activation of this process have likewise changed following alteration, in the case of micro, DeltaHdouble dagger, and DeltaSdouble dagger an increase of 20.6 kcal., 20.6 kcal., and 70 e.u., respectively, and of DeltaFdouble dagger a decrease of 2.8 kcal. 5. All these data have been shown to be consistent with, and in some cases predictable from, the interfacial hypothesis, which states that the unaltered catalase exists within the cell adsorbed to some interface, in a partially, but reversibly, unfolded configuration of relatively low specificity; enzyme alteration consists, in the case of catalase, of desorbing the enzyme from the interface into its rolled-up, soluble, highly specific configuration. While the interfacial hypothesis has successfully withstood this experimental attack, the present data do not provide its unequivocal proof, since they are consistent with any hypothesis of alteration in which the unaltered, intracellular enzyme is in a relatively disordered state by comparison to the altered enzyme. While evidence of an interfacial process in enzyme alteration has been adduced previously, critical proof of the interfacial hypothesis awaits creation of a model system, in which most of the aspects of intracellular alteration can be reproduced. 6. Certain of the changes in kinetic properties following alteration of the intracellular enzyme, such as increased activity and the modified energies and entropies of activation of both enzyme-substrate system and heat destruction of the catalase itself, might be explained by a decrease (two orders of magnitude) in the effective hydrogen ion concentration, allowing the intracellular enzyme to be brought to the same pH as the extracellular medium. If such a pH change does, in fact, occur, it is necessary to invoke the interfacial hypothesis to explain why the unaltered, intracellular enzyme is in equilibrium with a medium whose pH is approximately 2 units lower than that of the cytoplasm itself. 7. It is concluded that kinetic data of this kind may be used to shed light on the structure of a soluble, cytoplasmic enzyme, not attached to any of the formed elements within the cell, yet organized within it in a condition of relatively low structural specificity; further, that information obtained exclusively from a study of the kinetics of the extracted or crystalline enzymes may not, in the case of this enzyme, at least, be extrapolated to the same enzyme within the intact cell.

Animals↗
PubMed1961

Toxohormone-like factor from microorganisms with impaired respiration.

A substance that significantly depresses liver catalase values when injected into mice has been isolated from biochemical mutants of yeasts and staphylococci with impaired respiration. This is considered as an important argument in support of the Warburg hypothesis on the origin of cancer cells.

Animals↗
PubMed1962

Cytochrome and catalase patterns during growth of Haemophilus parainfluenzae.

White, David C. (The Rockefeller Institute, New York, N. Y.) Cytochrome and catalase patterns during growth of Haemophilus parainfluenzae. J. Bacteriol. 83:851-859. 1962.-By following the cytochrome and catalase concentrations during the growth cycle and under various growth conditions in Haemophilus parainfluenzae, a rapid increase in the cytochrome oxidases and a large increase in cytochrome c(1) concentration can be demonstrated between log-phase and stationary-phase cells and between vigorously aerated and anaerobic growth conditions. The three cytochrome oxidases develop differentially under various growth conditions. The principal oxidase formed in vigorously aerated cultures is cytochrome o. With limited aeration, maximal development of cytochrome a(2) occurs; with anaerobically grown cells, there is a marked increase in the concentration of cytochrome a(1). With the rapid increase in cytochrome c(1) concentration, soluble, nonenzymatically reducible cytochrome c(1) is also formed, which remains in the bacterial cell sap. From these data it is postulated that the electron-transport system is assembled from individual components which can be modified by the growth conditions. The cytochrome c(1) may be synthesized in the cell sap and then incorporated into the electron-transport system.

Catalase↗