Body Size and Performance of Pathways of Carbohydrate Metabolism in the Sea AnemoneMetridium senileL.

Abstract

Flux through glycolysis and the pentose shunt pathway and the rate of glucose oxidation to CO₂ were examined as functions of body mass in the sea anemone Metridium senile. Minced tissues from anemones acclimated to 5°C and 15°C were incubated in media containing isotopically labeled glucose compounds to determine pathway fluxes. Double-logarithmic regressions showed that the specific rate of glucose oxidation declined significantly with increasing anemone mass at 15°C (the mass exponent in the expression $Y = aM^{b}$ is b, and b-1 =-.210; P = .0321) but was mass-independent at 5°C. Pentose shuntflux scaled negatively with anemone mass at 5°C (b-1 =-. 063; P = .0124) but was mass-independent at 15°C. Regression of glycolytic flux versus anemone mass was significant at 5°C (b-1 =-.052; P = .0218) but not at 15°C, which was opposite the pattern observed for the glucose oxidation rate at these temperatures. Therefore, glycolytic flux and the glucose oxidation rate scaled independently. The mass exponents for ...