The number of identifiable stages and expression of differentiation markers in cells of the osteoblast lineage are not well understood. In the present study, a mAb, designated rat bone marrow (RBM) 211.13, was prepared that stained selectively the osteogenic and preosteoblastic cells along the surfaces of bone in calvariae, femurs, and metatarsals. The staining was cell surface associated and c...

The hepatotoxin cylindrospermopsin (CYN) produced by certain cyanobacteria, including Aphanizomenon ovalisporum (hereafter Aphanizomenon) [1], seriously affects lake water quality [2], but its biological role is not known. Strong correlation between Aphanizomenon abundance in Lake Kinneret, Israel, and alkaline phosphatase (APase) activity suggests that inorganic phosphate (Pi) limitation induc...

Both tomato (Lycopersicon esculentum cv VF 36) plants and suspension cultured cells show phosphate starvation inducible (psi) excretion of acid phosphatase (Apase). Apase excretion in vitro was proportional to the level of exogenous orthophosphate (Pi). Intracellular Apase activity remained the same in both Pi-starved and sufficient cells, while Apase excreted by the starved cells increased by ...

The gene encoding alkaline phosphatase from the psychrotrophic bacterium Shewanella sp. SIB1 was cloned, sequenced, and overexpressed in Escherichia coli. The recombinant protein was purified and its enzymatic properties were compared with those of E. coli alkaline phosphatase (APase), which shows an amino acid sequence identity of 37%. The optimum temperature of SIB1 APase was 50 degrees C, lo...

Acid phosphatase (APase) activity of the yeast Yarrowia lipolytica increased with increasing Cu2+ concentrations in the medium. Furthermore, the enzyme in soluble form was stimulated in vitro by Cu2+, Co2+, Ni2+, Mn2+ and Mg2+ and inhibited by Ag+ and Cd2+. The most effective ion was Cu2+, especially for the enzyme from cultures in medium containing Cu2+, whereas APase activity in wall-bound fr...

The expression and secretion of acid phosphatase (APase) was investigated in Indian mustard (Brassica juncea L. Czern.) plants using sensitive in vitro and activity gel assays. Phosphorus (P) starvation induced two APases in Indian mustard roots, only one of which was secreted. Northern-blot analysis indicated transcriptional regulation of APase expression. Polymerase chain reaction and Souther...

Southern transfer analysis of Bacillus licheniformis MC14 DNA, using as probe a DNA fragment from within the coding region of a previously cloned alkaline phosphatase (APase) gene, revealed a second area of hybridization adjacent to the cloned APase gene. A second APase gene (APase II) was subcloned from the same plasmid clone, pMH8, from which the first APase gene (APase I) had been subcloned....

Phosphorus (P) acquisition and partitioning are essential for plant homeostasis. P is available for plant uptake when in its inorganic form (H2PO4-, or Pi), but Pi is often limiting in soils. Plants secrete acid phosphatases (APases) into the apoplastic space, which may be important for obtaining Pi from organic P sources; however, the relative importance of these enzymes for plant P nutrition ...

Phosphatase (APase) enzymes including phytases have broad applications in diagnostic kits, poultryfeeds, biofertilizers and plant nutrition. Because of high levels of sequence diversity among phosphatases,an efficient functional screening method is a crucial requirement for the isolation of the encodinggenes. This study reports a functional cloning screening method for the iso...

Despite its agronomic importance, the metabolic networks mediating phosphorus (P) remobilization during plant senescence are poorly understood. Highly efficient P remobilization (~85%) from senescing leaves and proteoid roots of harsh hakea (Hakea prostrata), a native 'extremophile' plant of south-western Australia, was linked with striking up-regulation of cell wall-localized and intracellular...