Protein phosphorylation of beta-glucuronidase in human lung cancer--identification of serine- and threonine-phosphates.
Slices of human lung cancer tissue were incubated with [32P]-orthophosphoric acid, and the radiolabeled beta-glucuronidase was isolated by a procedure including immunoaffinity chromatography on anti-human liver beta-glucuronidase IgG Sepharose. Following removal of endo-beta-N-acetyl-glucosaminidase H-releasable carbohydrate portions of the enzyme, the protein moiety was acid-hydrolyzed. Two-dimensional separation of the hydrolysate identified phosphoserine and phosphothreonine. This is the first demonstration of protein phosphorylation in lysosomal beta-glucuronidase.
D000230:Adenocarcinoma / Q000201:enzymology; D055598:Chemical Phenomena; D002621:Chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005966:Glucuronidase / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D005779:Immunodiffusion; D008099:Liver / Q000201:enzymology; D008168:Lung / Q000201:enzymology; D008175:Lung Neoplasms / Q000201:enzymology*; D010766:Phosphorylation; D010768:Phosphoserine / Q000378:metabolism*; D010769:Phosphothreonine / Q000378:metabolism*; D012694:Serine / Q000031:analogs & derivatives*; D013912:Threonine / Q000031:analogs & derivatives*
D010769:Phosphothreonine; D010768:Phosphoserine; D013912:Threonine; D012694:Serine; D005966:Glucuronidase