Bacterial alkaline phosphatases (PhoA) hydrolyse phosphate-containing substrates to provide the preferred phosphorus source inorganic phosphate (P(i)). Campylobacter jejuni does not contain a typical PhoA homologue but contains a phosphatase that is regulated by the two-component system PhosS/PhosR. Here we describe the characterization of the enzyme, its secretion pathway and its function in t...

Phosphatases have been extensively studied in soil, as shown by some reviews (Ramirez-Martinez 1968; Speir and Ross 1978; Malcom 1983; Tabatabai 1994), because they catalyse the hydrolysis of ester–phosphate bonds, leading to the release of phosphate (P), which can be taken up by plants or microorganisms (Cosgrove 1967; Halstead and McKercher 1975; Quiquampoix and Mousain 2005). It has been sho...

The molecular structure of human foetal intestinal alkaline phosphatase was defined by high-resolution two-dimensional polyacrylamide-gel electrophoresis and amino acid inhibition studies. Comparison was made with the adult form of intestinal alkaline phosphatase, as well as with alkaline phosphatases isolated from cultured foetal amnion cells (FL) and a human tumour cell line (KB). Two non-ide...

The inhibitory effect of a marine-sponge toxin, okadaic acid, was examined on type 1, type 2A, type 2B and type 2C protein phosphatases as well as on a polycation-modulated (PCM) phosphatase. Of the protein phosphatases examined, the catalytic subunit of type 2A phosphatase from rabbit skeletal muscle was most potently inhibited. For the phosphorylated myosin light-chain (PMLC) phosphatase acti...

A system for detecting the effects of metal ions, repressors, and mutations on the biosynthesis in vivo of alkaline phosphatase of Escherichia coli is described. If E. coli constitutive for alkaline phosphatase are grown in a medium containing 65Zn and are subject to osmotic shock, about 50% of the zinc taken up by the cells is released into the medium. Chromatography of this medium shows that ...

The aim of this study was to determine the correlation between the level of calcium in the mandible and teeth and the level of alkaline and acid phosphatases in ovariectomized rats with or without supplementation of 17β-estradiol. Rats were qualified for the following groups: Cl – control, SH – sham operated, OV – ovariectomized, OVH – ovariectomized and receiving 17β-estradiol in three differe...