The distribution of cytochrome oxidase, glucose-6-phosphatase and esterase in the fractions of liver cells prepared from glycerol homogenates

Abstract

Cytochrome oxidase activity was used to measure the distribution of the mitochondrial fraction and glucose-6-phosphatase and esterase activities for the distribution of the microsomal fraction prepared from glycerol homogenates of mouse liver. The mitochondrial fraction obtained from the fractionation of the glycerol homogenate in a solution containing 12% glycerol, 0.25 M sucrose, and 1.28 × 10 −2 M NaCl had a specific activity of cytochrome oxidase comparable to that found for these particulates isolated from sucrose homogenates fractionated in 0.25 M sucrose. The specific activity of glucose-6-phosphatase in the microsomal fraction isolated from glycerol homogenates by fractionation in a solution containing 12% glycerol, 0.25 M sucrose, and 8.5 × 10 −3 M and 1.28 × 10 −2 M NaCl was somewhat less than that obtained for these particulates isolated from the differential centrifugation of sucrose homogenates in 0.25 M sucrose or in 0.25 M sucrose containing 8.5 × 10 −3 M NaCl. The specific activity of esterase in the microsomal fraction isolated from sucrose homogenates by fractionation in a solution containing sucrose or in sucrose containing 8.5 × 10 −3 M or 1.28 × 10 −2 M NaCl was of the same order of magnitude. Glycerol homogenates fractionated in 12% glycerol and 0.25 M sucrose containing 4.28 × 10 −3 M or 8.5 × 10 −3 M NaCl resulted in supernatant fractions which had about one-half the total esterase activity and a microsomal fraction which had a much lower specific activity than those isolated in sucrose or in sucrose-NaCl solutions.