Chemical nature of intestinal-type alkaline phosphatase in human kidney

Clin Chem. 1992 Dec;38(12):2539-42.

Abstract

Approximately 10% of the alkaline phosphatase activity in human kidney is derived from the intestinal-type alkaline phosphatase isoform, which can be differentiated from adult intestinal alkaline phosphatase by selective reactivity with monoclonal antibodies. The NH2-terminal sequence of the renal intestinal-type alkaline phosphatase was shown to be identical to sequences of the adult and meconial alkaline phosphatases except for the NH2-terminal valine residue, which is missing in the renal intestinal-type enzyme. Incubation of purified meconial alkaline phosphatase with kidney homogenate resulted in removal of the NH2-terminal valine residue, indicating the presence of aminopeptidases in kidney that catalyze this hydrolysis. Furthermore, the oligosaccharide chains of the renal intestinal-type alkaline phosphatase were shown to differ from those of meconial and adult intestinal alkaline phosphatases, as revealed by lectin affinity chromatography. The heterogeneity of the intestinal-type alkaline phosphatase can therefore be generated both by partial peptide bond hydrolysis and differences in glycosylation.

Publication types

  • Comparative Study

MeSH terms

  • Alkaline Phosphatase / chemistry*
  • Alkaline Phosphatase / metabolism
  • Amino Acid Sequence
  • Endopeptidases / metabolism
  • Glycosylation
  • Humans
  • Intestines / embryology
  • Intestines / enzymology*
  • Isoenzymes / chemistry*
  • Isoenzymes / metabolism
  • Kidney / enzymology*
  • Liver / enzymology
  • Meconium / enzymology
  • Molecular Sequence Data
  • Neuraminidase / metabolism

Substances

  • Isoenzymes
  • Alkaline Phosphatase
  • Neuraminidase
  • Endopeptidases