Intracellular Distribution of Hexosamine and Sialic Acid in Rabbit Liver

抄録

1. Rabbit liver homogenate was frac-tionated into nuclear, mitochondrial, micro-somal and supernatant fractions. A purified nuclear fraction was prepared by an inde-pendent procedure. The fractions were ex-amined for purity by chemical and enzymatic analysis.
2. Hexosamine and sialic acid were de-termined on the subcellular fractions with particular attention paid for sialic acid de-termination. Most of these sugars were found to be localized in mitochondria and micro-some, the contents of hexosamine and sialic acid (μg. per mg. protein) being 7.5 and 3.2 for mitochondria and 8.9 and 8.0 for micro-some respectively.
3. Contamination of the purified nuclear fraction with connective tissue was tried to be assessed by analyzing hydroxyproline and a conclusion was drawn that nuclei contain very small amounts of hexosamine and sialic acid, if any.
4. Biological importance of the intra-cellular distribution of hexosamine and sialic acid was discussed in particular connection with membranous structures of liver cells.
Support was provided by grants from the Ministry of Education, Japan.