Respiration, regulatory mechanisms

Keywords. Xylose, Fermentation, Respiration, Metabolic engineering. Regulation, Regulatory mechanisms. Pentose metabolism. Oxygen regulation. Glucose regulation... 

Barron, E. S. G., L. Nelson, and M. I. Ardao Regulatory mechanisms of cellular respiration 2. The role of soluble sulfhydryl groups as shown by the effect of sulfhydryl reagents on the respiration of sea urchin sperm. J. Gen. Physiol. 32, 179 (1948). 

The cellular mechanism of lead nephrotoxicity appears to be due to an alteration of calcium homeostasis. Lead (Pb ) competes with calcium (Ca " ") for transport, binding to calmodulin and at other cell calcium regulatory sites. Lead can accumulate in mitochondria using the calcium transporter and disrupt respiration. Interactions of lead with calmodulin can result in a disruption of the calcium messenger system to adversely affect normal cell function. The nuclear inclusion bodies may also alter the cellular function of DNA, although this interaction has not been fully elucidated. 

The results of experiments to be described below appear to show that anoxia and cell poisons which inhibit respiratory chain phosphorylation stimulate uptake of glucose by muscle and that under suitable conditions respiration of fatty acids and ketone bodies can lead to inhibition of glucose uptake. Since fatty acids and ketone bodies are oxidized by mitochondria and since the effects of anoxia and of these cell poisons will be exerted principally on mitochondrial metabolism it seems reasonable to accept these findings as common evidence for a regulatory effect of mitochondrial metabolism on glucose uptake. It is recognized that this concept is provisional until such time as the mechanism of this regulation has been established. 

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