Metabolism advantages

What is the metabolic advantage of having the committed step of a pathway under strict regulation ... 

Torasemide is a long-acting loop diuretic promoted for use in hypertension. Like piretanide, it is claimed to be potassium neutral, but the assertion is premature. There is no evidence that torasemide has metabolic advantages over thiazides (SEDA-16, 226) (SEDA-17, 264) (SEDA-18, 237). 

Reflect and Apply What is the metabolic advantage in the conversion of glucose to lactate, in which there is no net oxidation or reduction ... 

The oxygen so produced was released into the atmosphere and gradually came to be its most important constituent. With abundant oxygen, other life-forms appeared that could use the highly reactive nature of oxygen to their metabolic advantage. It was not an easy trick oxygen can be toxic as well as a metabolic enhancer. 

The coupling of reaction sequences through the adenylate system is entirely different from the two types of stoichiometric relationships discussed above. The stoichiometry of each reaction in which ATP is regenerated or used is, of course, fixed by the nature of the reaction, but the number and types of reactions in which ATP is involved have been determined by evolutionary processes, rather than by simple chemical necessity. Indeed the use of ATP as a coupling agent and the evolutionary adjustments of stoichiometric relationships for maximal metabolic advantage are at the very center of biological function. This fact is underscored by the participation of ATP in every extended metabolic sequence. 

Because there is evidence of both diffusion- and conduction-based EET in S. onei-densis, we hypothesize that there must be a metabolic advantage for having both mechanisms. The model demonstrates that if the biolilm conductivity is low, if the biofilm half-maximum rate potential and mediator standard reduction potential are different, and/or if the terminal electron acceptor potential is very low, then there may be an advantage to having both mechanisms available concurrently. Later in this chapter, it is shown that having both diffusion- and conduction-based EET mechanisms further improves the current production if the mechanisms are allowed to interact (i.e., interacting-dual EET). 

In summary, our simulation results show that the availability of diffusion-based EET does not contribute to increased biofilm metabolism unless conduction-based EET is restricted or unavailable. As a specific case, when the electrode potential is equal to the half-maximum rate potential, the total current can increase when some diffusion-based EET is allowed, although the overall coulombic efficiency drops. Einally, under natural conditions, having both mechanisms available could provide a metabolic advantage for S. oneidensis. 

Under environmental, limited nutrient, or stressful conditions, having both mechanisms available may provide a metabolic advantage for S. oneidensis ... 

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