Metabolism cellular

The effects of ampicillin-induced spheroplast formation on the production of molecular hydrogen by Escherichia coli carrying out fermentation in a lactose-peptone broth with an osmolality of 342 mosmol/1 was investigated previously 

The production of molecular hydrogen was measured in the effluent gas of seven fermentations [58]. The aim of this primary investigation was to study the use of a H2-sensitive metal-oxide-semiconductor structure in physiological studies of Escherichia coli. In order to yield more information, the metabolic heat was measured with a flow micro calorimeter in parallel with the determination of molecular hydrogen. 

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Nearly all biological processes involve the specialized functions of one or more protein molecules. Proteins function to produce other proteins, control all aspects of cellular metabolism, regulate the movement of various molecular and ionic species across membranes, convert and store cellular energy, and carry out many other activities. Essentially all of the information required to initiate, conduct, and regulate each of these functions must be contained in... 

Thyroid gland. An endocrine gland that secretes thyroxin and triiodothyronine, hormones that modulate the rate of cellular metabolism. 

FIGURE 5.3 Different types of functional readouts of agonism. Receptors need not mediate cellular response but may demonstrate behaviors such as internalization into the cytoplasm of the cell (mechanism 1). Receptors can also interact with membrane proteins such as G-proteins (mechanism 2) and produce cytosolic messenger molecules (mechanism 3), which can go on to mediate gene expression (mechanism 4). Receptors can also mediate changes in cellular metabolism (mechanism 5). 

Methotrexate belongs to the class of antimetabolites. As a derivative of folic acid it inhibits the enzyme dihydrofolate reductase resulting in a decreased production of thymidine and purine bases essential for RNA and DNA synthesis. This interruption of the cellular metabolism and mitosis leads to cell death. 

Nichols CG (2006) KATP channels as molecular sensors of cellular metabolism. Nature 440(7083) 470-476... 

Metabolic diseases In the pancreatic (3-cells, KATP channel derived from >SUR1 and Kir6.2, links cellular metabolism to electrical activity and regulates insulin secretion. Mutations in SUR1 and Kir6.2 that result in loss of Katp channel function have been identified in families with familial persistent hyperinsulinemic hypoglycemia of infancy (PHHI). 

Insulin, a hormone produced by the pancreas, acts to maintain blood glucose levels within normal limits (60-120 mg/dL). This is accomplished by die release of small amounts of insulin into die bloodstream tiirough-out the day in response to changes in blood glucose levels. Insulin is essential for die utilization of glucose in cellular metabolism and for die proper metabolism of protein and fat. 

FIGURE 49-1. Normal glucose metabolism. Once insulin binds with receptors on the cell membrane, glucose can move into the cell, promoting cellular metabolism and energy production. 

Panthenol is the alcohol form of pantothenic acid, more familiar as vitamin B5. In a living cell, panthenol is converted to pantothenic acid, which then becomes an important part of the compound coenzyme A, which is important in cellular metabolism. In hair, which contains no living cells, it remains panthenol. 

Function and Regulation of Temperature-Inducible Bacterial Proteins on the Cellular Metabolism 3... 

Analytical models of the heart are a reality. They are based on detailed descriptions of cardiac tissue architecture and anatomy, including the coronary vasculature. In sihco cardiac tissues possess realistic passive mechanical properties, and both electrical and mechanical activity can be simulated with high accuracy. Descriptions of key components of cellular metabolism have been introduced, as have models of drug-receptor interactions. 

As stated in section 5.1.1, some bacteria derive energy from food sources without the use of oxygen, whereas others are able to use this gas. The pathway of oxygen utilization itself is also a stepwise series of reactions and thus the overall picture emerges of cellular metabolism characterized by multistep reactions. 

Ubiquinone, known also as coenzyme Q, plays a crucial role as a respiratory chain electron carrier transport in inner mitochondrial membranes. It exerts this function through its reversible reduction to semiquinone or to fully hydrogenated ubiquinol, accepting two protons and two electrons. Because it is a small lipophilic molecule, it is freely diffusable within the inner mitochondrial membrane. Ubiquinones also act as important lipophilic endogenous antioxidants and have other functions of great importance for cellular metabolism. ... 

Carmen Socaciu was bom in Cluj-Napoca, Romania and earned a BSc in chemistry in 1976, an MSc in 1977, and a PhD in 1986 from the University Babes-Bolyai in Cluj-Napoca, an important academic centre located in the Transylvania region. Dr. Socaciu worked as a researcher in medical and cellular biochemistry for more than 10 years, and became a lecturer in 1990 and full professor in 1998 in the Department of Chemistry and Biochemistry of the University of Agricultural Sciences and Veterinary Medicine (USAMV) in Cluj-Napoca. She extended her academic background in pure chemistry (synthesis and instrumental analysis) to the life sciences (agrifood chemistry and cellular biochemistry). Her fields of competence are directed especially toward natural bioactive phytochemicals (carotenoids, phenolics, flavonoids), looking to advanced methods of extraction and analysis and to their in vitro actions on cellular metabolism, their effects as functional food ingredients, and their impacts on health. 

The major determinant of myocardial redox status is the glutathione content of the heart (Griffith and Meister, 1979). Therefore, fluctuations in myocardial glutathione status may exert a regulatory role in cellular metabolism in a comparable manner to the phosphorylation and dephosphorylation of proteins and enzymes. 

Deprived of their substrate in severe or prolonged hypoxia, some ATPase-driven systems, including ion pumps, may become impaired. Further, with the decrease in the availability of O2 as its terminal electron acceptor, the mitochondrial transport chain becomes increasingly unable to accept reducing equivalents from cellular metabolic processes. Hence the intracellular pH falls, subjecting the cell as a whole to a reductive stress and favouring those enzyme systems with acid pH optima. 

We postulate that the double13C -labeling technique presented in this chapter could be used to study adducts on large pieces of DNA and even follow the chemical details cellular metabolic processes in real time. The double 13C-labeling technique is currently being developed to solve problems in metabolism and toxicology. 

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