Catabolic Activity

Comparison of the model-derived DIFF with the experimentally evaluated DIFF show that protein routing can be described in terms of the amount of protein synthesized from catabolic activity that is, in general it is around 20% of the mean carbon flux of the diet. A simple explanation why dp > dw is also proposed. 

McClure NC, Fry JC, Weightman AJ (1991) Survival and catabolic activity of natural and genetically engineered bacteria in laboratory-scale activated sludge unit. Appl Env Microbiol 57 366-373... 

Microorganisms must exist, which have the needed catabolic activity and ability to transform the contaminant at a reasonable rate, reducing the contaminant concentration to levels that meet regulatory standards. 

The drug-LMWP conjugate is stable in the circulation but after arrival in the kidney, the active drug is released in the catabolically-active lysosomes of the proximal tubular cells (Figure 5.7). 

Hlklno et at. (1975) showed that the catabolic activity on fl-ecdysone of B. mon varied during the course of Its growth and development. This Is Illustrated In Tables 2 and 6 In which It can be seen that the larvae are more sensitive to either Ingested (Table 6) or Injected (Table 2) fl-ecdysone during the earlier phase of the fourth instar. 

Somewhat surprisingly, within the mitochondria the ratio [NAD+]/[NADH] is 100 times lower than in the cytoplasm. Even though mitochondria are the site of oxidation of NADH to NAD+, the intense catabolic activity occurring in the (3 oxidation pathway and the citric acid cycle ensure extremely rapid production of NADH. Furthermore, the reduction state of NAD is apparently buffered by the low potential of the (3-hydroxybutyrate-acetoacetate couple (Chapter 18, Section C,2). Mitochondrial pyridine nucleotides also appear to be at equilibrium with glutamate dehydrogenase.169... 

The fluorinated glucocorticoids are said to have relatively more catabolic activity than others and might have a greater effect on the skeleton but such impressions may merely reflect the general potency of some newer glucocorticoids and a tendency to use them in inappropriate doses. A relatively new glucocorticoid, deflazacort, has been proposed to have less effect on bone metabolism, but a double-blind study has failed to show an advantage compared with prednisolone (SEDA-21, 417 194). 

Usually these three biophysical mechanisms interact precisely to provide a highly efficient barrier against water loss and retain water within the tissue to maintain flexibility and catabolic activity. Nevertheless, this barrier is continually prone to perturbation by both external forces (UV, low RH, cold temperatures, and surfactants), and internal factors (cutaneous disease, psychological stress, and diabetic complications). With decreased performance of the water barrier the increased loss of water from the tissue ultimately leads to the formation of dry skin. 

Hyaluronan is very metabolically active, with a half-life of 3 to 5 min in the circulation,less than one day in skin, and even in an inert a tissue as cartilage, the HA turns over with a half-life of 1 to 3 weeks.66,67,184 This catabolic activity is primarily the result of hyaluronidases, endoglycolytic enzymes with a specificity in most cases for the ft 1 1 glycosidic bond. 

Such observations may be applicable to the hyaluronasome. A multiprotein membrane-associated complex that contains HA synthetic activity has been described.42 233 This hyaluronate synthase complex may be a component of the hyaluronasome, containing synthetic as well as catabolic activities, a functional unit that could provide response mechanisms dependant on the metabolic state of the cell. 

Segment Surface area Segment length Residence time pH of segment Catabolic activities... 

Increased lipoprotein levels are seen in diabetes mellitus but not in starvation. Glucocorticoids have a protein catabolic activity in all tissues except liver. There, glucocorticoids stimulate protein synthesis. 

Pyruvate-dependent aldolases have catabolic activity in vivo, whereas their counterparts utilizing phosphoenolpyruvate as the donor substrate are involved in the biosynthesis of keto acids. Both classes of enzymes have been used in synthesis to prepare similar a-keto acids. The enzymes catalzye this type of reaction in vivo and their stereoselectivity are presented together in this section (Schemes 5.27, 5.28). 

Microorganisms must exist that have the needed catabolic activity (i.e., capacity to degrade organic matter)... 

This review aims to present some of the more interesting molecules containing inositol synthesized by bacterial and archaeal cells, and to describe what is known about their biosynthesis. A brief review of bacterial and archaeal inositol biosynthesis and catabolic activities is also provided. 

The detection of PI in bacterial and archaeal systems implies that PI synthase, which is an integral membrane protein, is present. Once PI is available, kinases could add phosphates to generate various phosphoinositides, although to date this chemistry has only been demonstrated to occur in eukaryotes. Bacterial catabolic activities specific to PI have also been identified. In most cases these are secreted soluble proteins that can cleave PI and in some cases GPI-anchored... 

Proliferation of chondrocytes and an increase in ECM anabolic and catabolic activity secondary to tissue damage or alterations in ECM structure... 

Uncoupling proteins confer to the brown adipocyte the ability to catabolize fatty acids without the usual concomitant ATP production and dissipate the heat generated by this excessive catabolic activity to other tissues via the bloodstream (Fig. 4). This process is known as thermogenesis and is characterized on two levels (M. Klingensport, 2003). 

Lysosomes are involved in a great variety of catabolic activities. The machinery for autolysis of animal tissue apparently resides in the lysosomal particle. Lysosomal enzymes are capable of the complete hydrolysis of proteins to amino acids (59). The hydrolytic reactions of lysosomal enzymes have been implicated in tenderization during the aging of meat (31, 47, 60-66). 

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