The study of metabolic turnover rates by means of isotopic tracers. I. Fundamental relations.

摘要: Abstract A formal definition of rate turnover, in agreement with general usage, has been proposed, and compared informally defned quantities frequently used. The prerequisites for the calculation turnover rates from experimental data have determined. It is found that any component a metabolic network requires complete knowledge structure network, as well study concentrations specific activities all its components. reasonably time curve each must be obtained. above proves to inadequate when reactions order higher than first occur. When compound labeled isotope may more one position within molecule, various species molecules dealt separately, both theoretically experimentally. Only some specially simple cases it possible combine equations into single whole. These points are illustrated by means C02 fixation through tricarboxylic acid cycle. consequences these findings discussed. Particular consideration given problem systems whose not completely known. Conditions under which obtained on such at least approximately interpreted terms described.