Human glycerol kinase: comparison of properties from fibroblasts and liver

Kinetic differences in the glycerol kinase activities from human liver and fibroblasts have been previously demonstrated by this laboratory. The present study was undertaken to characterize these enzymatic activities more completely. The pH profiles were similar for the hepatic and fibroblast activities, but the stability of hepatic glycerol kinase varied much more markedly with pH than the fibroblast activity. Subcellular distribution of this enzymatic activity was quite different for liver and fibroblasts, as was the electrophoretic mobility of these activities on polyacrylamide gels. While these data do not distinguish between tissue specific isozymic forms or post-transcriptional modification, hepatic and fibroblast activities are altered similarly in patients with an inherited deficiency of glycerol kinase.