Fraction of total respiration rate that is due to Ca2+ ATPase

Value 10.2 % of total respiration rate Range: Table - link % of total respiration rate
Organism Rat Rattus norvegicus
Reference Buttgereit F, Brand MD. A hierarchy of ATP-consuming processes in mammalian cells. Biochem J. 1995 Nov 15 312 ( Pt 1):163-7. p.164 table 1PubMed ID7492307
Primary Source [9] Buttgereit F, Grant A, Müller M, Brand MD. The effects of methylprednisolone on oxidative phosphorylation in Concanavalin-A-stimulated thymocytes. Top-down elasticity analysis and control analysis. Eur J Biochem. 1994 Jul 15 223(2):513-9PubMed ID8055921
Method Abstract: "The rates of different ATP-consuming reactions were measured in concanavalin A-stimulated thymocytes, a model system in which more than 80% of the ATP consumption can be accounted for." Primary source abstract: "[Investigators] have used top-down elasticity analysis to identify the blocks of reactions within oxidative phosphorylation in thymocytes whose kinetics are significantly affected by treatment with methylprednisolone…[they also used] Metabolic control analysis…"
Comments P.163, bottom of page: "Abbreviations used: Con A, concanavalin A FCCP, carbonyl cyanide p-trifluoromethoxyphenylhydrazone JATP, flux through ATP in units of the oxygen consumption used to drive it C, control coefficient, defined as the fractional change in a variable (usually flux) caused by an infinitesimal fractional change in a system parameter when the system is allowed to relax to a new steady state Ɛ, elasticity, defined as the fractional change in a local flux caused by an infinitesimal fractional change in a system variable when the system is not allowed to relax Δѱ, mitochondrial membrane potential." P.165 right column 3rd paragraph: "Control over the reactions around cytoplasmic ATP: ATP producers and ATP consumers-First, [investigators] calculated the control over ATP production rate exerted by each of the individual blocks of ATP-consuming reactions (protein synthesis, sodium cycling, calcium cycling, RNA/DNA synthesis and unidentified ATP consumers). By subtracting the oxygen consumption used to drive the proton leak [primary source] from the total oxygen consumption rate, [they] calculated the rate of ATP production in terms of the oxygen consumption needed to drive it (glycolytic ATP production is negligible under [their] conditions). From the measured rates of the ATP consumers [they] then calculated the fraction of ATP production used by each of the individual blocks of ATP-consuming reactions (Table 1). From the branching theorem of control analysis [ref 21] [they] know that control over the rate of ATP production is divided among the ATP consumers in the ratio of their fluxes. The reactions with the largest fluxes had the greatest share of the control over ATP production rate (Table 1)." See note above table
Entered by Uri M
ID 116168