Chemical nature of intestinal-type alkaline phosphatase in human kidney.
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.
Nishihara
Y
Y
Department of Pharmaceutics, Gifu Pharmaceutical University, Japan.
Hayashi
Y
Y
Adachi
T
T
Koyama
I
I
Stigbrand
T
T
Hirano
K
K
D000469:Alkaline Phosphatase / Q000737:chemistry* / Q000378:metabolism; D000595:Amino Acid Sequence; D010450:Endopeptidases / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D007422:Intestines / Q000196:embryology / Q000201:enzymology*; D007527:Isoenzymes / Q000737:chemistry* / Q000378:metabolism; D007668:Kidney / Q000201:enzymology*; D008099:Liver / Q000201:enzymology; D008470:Meconium / Q000201:enzymology; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000378:metabolism
D007527:Isoenzymes; D000469:Alkaline Phosphatase; D009439:Neuraminidase; D010450:Endopeptidases