Logo image
Back
Effect of phosphorus deficiency on phosphatase activity of cell walls from roots of subterranean clover
Journal article   Peer reviewed

Effect of phosphorus deficiency on phosphatase activity of cell walls from roots of subterranean clover

M.N.H. Dracup, E.G. Barrett-Lennard, H. Greenway and A.D. Robson
Journal of Experimental Botany, Vol.35(4), pp.466-480
1984
DOI: https://doi.org/10.1093/jxb/35.4.466
url
Link to Published Version *Subscription may be requiredView

Abstract

Clover (Trifolium subterraneum L. cv. Mt. Barker) was grown in solution culture with adequate (+P) or no phosphate (−P). Cell walls were extracted from roots in such a way that they were uncontaminated by other cellular materials. Phosphatase activity was assayed using p-nitro-phenylphosphate (NPP). Phosphatase bound to cell walls had a pH optimum between 5.0 and 6.0, irrespective of the P supply to the plants. Activity of phosphatase bound to cell walls increased with electrolyte concentration of the assay medium at pH 6.5 but not at pH 5.5. This increase in activity was probably due to a higher degree of ionization of the cell wall at pH 6.5 than at pH 5.5, and to effects of high ionic strength in decreasing the mutual repulsion of negatively charged NPP from negative charges on the cell walls. Cell wall-bound phosphatase did not exhibit Michaelis-Menten kinetics: the concentration of NPP at which activity was half the maximum rate (S0.5) was 0.7 mM for cell walls extracted from roots of both +P and −P plants. Up to 30% of the phosphatase activity bound to cell walls could be removed using buffer solutions of high pH and high ionic strength which contained Triton X100. Both soluble and cell wall-bound phosphatase(s) of roots increased in activity with P deficiency. The phosphatase activity of cell walls increased 1.5 fold as the P concentration in the roots fell from 0.4–0.2% dry weight. Experiments with sterile roots of clover showed that increases in cell wall-bound phosphatase activity associated with P deficiency were not due to microbial contamination. It is argued that phosphatase(s) in cell walls of roots could make a substantial contribution to the P nutrition of clover in soils deficient in inorganic phosphate by hydrolysing organic phosphate compounds in the soil.

Details

UN Sustainable Development Goals (SDGs)

This output has contributed to the advancement of the following goals:

#2 Zero Hunger

Source: InCites

Metrics

33 Record Views
61 Times Cited - Web of Science

InCites Highlights

These are selected metrics from InCites Benchmarking & Analytics tool, related to this output

Citation topics
3 Agriculture, Environment & Ecology
3.45 Soil Science
3.45.473 Soil Phosphorus Dynamics
Web Of Science research areas
Plant Sciences
ESI research areas
Plant & Animal Science
Logo image