Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1988 Dec 5;263(34):18513-9.

Correlation between loss of alkaline phosphatase activity and accumulation of calcium during matrix vesicle-mediated mineralization

B R Genge  1 , G R Sauer, L N Wu, F M McLean, R E Wuthier
Affiliations
  • PMID: 3192545
Free article

Correlation between loss of alkaline phosphatase activity and accumulation of calcium during matrix vesicle-mediated mineralization

B R Genge et al. J Biol Chem. .
Free article

Abstract

Activity of the bone/liver/kidney isozyme of alkaline phosphatase (AP) is known to be critical for mineralization in developing bone, although its role is unclear. The work now reported explores changes in the activity of this Zn2+-containing enzyme that occur during Ca2+ accumulation by matrix vesicles (MV). A marked loss (up to 65-70%) in AP activity was found to accompany Ca2+ accumulation by MV. These two events were highly correlated, both temporally and quantitatively. Investigation into possible causes revealed that the decline in AP activity during Ca2+ uptake was not due to action of proteases but rather resulted from interaction with the developing mineral phase, loss of metal ions (Zn2+ and Mg2+) from the active site of the enzyme, and concomitant irreversible denaturation of the enzyme. Protease inhibitors did not protect AP from loss of activity during mineralization; in contrast, protease treatments, which progressively destroyed the ability of MV to accumulate Ca2+ actually reduced loss of AP activity. These findings clearly demonstrate that AP is present at the site of MV mineralization and that its catalytic activity is profoundly reduced by the mineralization process.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

Publication types

LinkOut - more resources