Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.8 (phytase)
 1,997 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Postweaning protein malnutrition imposed on normally weaned or neonatally undernourished rats fed a low-protein diet induced retardation of body and small intestinal growth. A sparing effect on intestinal growth as compared to body growth was observed during protein malnutrition. Postweaning protein malnutrition in normally weaned rats resulted in a significant elevation of specific activities of inositol triphosphatase and phytase in duodenum and jejunum without affecting the activity in ileum. On the other hand, protein malnutrition imposed on neonatally undernourished rats resulted in a significant decrease of enzyme activities in small intestinal segments. These results suggest altered activity of intestinal inositol phosphatase in postweaning protein malnutrition with the direction of effects dependent on the neonatal nutritional status.
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PMID:Effects of postweaning protein malnutrition on intestinal inositol phosphatase activities in normally weaned and neonatally undernourished rats. 216 59

Inositol phosphatase and phytase activities in different segments of the rat small intestine were measured during postnatal development. In the duodenum and jejunum, inositol phosphatase activity (units/g tissue) was low during the suckling period and increased at weaning, reaching a peak of activity at 4 weeks of age. In the ileum, peak activity was observed during the suckling period with a sharp decline at weaning. Phytase activity was very low during the suckling period in all segments, and increased to exhibit a peak at 4 weeks of age in the duodenum, and to a lesser extent in the jejunum (low activity was maintained in the ileum). The content of inositol phosphatase activity in the duodenum increased rapidly during the suckling period to reach its maximum at 4 weeks of age. This suggests a relationship to cell proliferation rate in the small intestinal mucosa.
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PMID:Inositol phosphatase in developing rat duodenum, jejunum and ileum. 302 Dec 46

Inositol phosphates are recognized as having diverse and critical roles in biological systems. In this report, kinetic studies and TLC analysis indicate that beta-propeller phytase is a special class of inositol phosphatase that preferentially recognizes a bidentate (P-Ca(2+)-P) formed between Ca(2+) and two adjacent phosphate groups of its natural substrate phytate (InsP(6)). The specific recognition of a bidentate chelation enables the enzyme to sequentially hydrolyze one of the phosphate groups in a bidentate of Ca(2+)-InsP(6) to yield a myo-inositol trisphosphate (InsP(3)) and three phosphates as the final products. A comparative analysis of (1)H- and (13)C NMR spectroscopy with the aid of 2D NMR confirms that the chemical structure of the final product is myo-Ins(2,4,6)P(3). The catalytic properties of the enzyme suggest a potential model for how the enzyme specifically recognizes its substrate Ca(2+)-InsP(6) and produces myo-Ins(2,4,6)P(3) from Ca(2+)-InsP(6). These findings potentially provide evidence for a selective Ca(2+)-InsPs chelation between Ca(2+) and two adjacent phosphate groups of inositol phosphates.
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PMID:Ca(2+)-inositol phosphate chelation mediates the substrate specificity of beta-propeller phytase. 1687 87