Root surface acid phosphatases and their role in phosphorus assimilation by Eriophorum vaginatum
Abstract
Eriophorum vaginatum is a dominant plant in much of the arctic tundra ecosystem where phosphorus is frequently a limiting nutrient. The mineralization of this organic phosphorus was thought to be principally controlled by microbial respiration, however, more recent work shows that extracellular soil phosphatases are the principal regulators. The existence of plant root and mycorrhizal surface phosphatases which are capable of hydrolyzing organic phosphorus compounds, suggests that soil organic phosphorus may be directly utilized by plants. Since E. vaginatum is a tussock forming sedge with a very dense annually produced rooting system which can exploit most of the tussock soil volume, its surface phosphatases may play a dominant role in organic phosphorus hydrolysis into inorganic phosphorus. Of equal significance would be the potential for this activity to contribute to the phosphorus nutrition through the coupling of phosphorus hydrolysis on the root and root uptake of the resultant inorganic phosphorus. Phosphatase activity was investigated and found to be uniformly distributed along the surface of the root. Kinetic analysis of the enzyme gave estimates of 9.23 mM for the apparent Km and 1.61 * 10/sup -3/ ..mu..moles mm-2 hr/sup -1/ for the apparent Vmax. Saturation values for E. vaginatum phosphatases are aboutmore »
- Authors:
- Publication Date:
- Research Org.:
- Clarkson Univ., Potsdam, NY (USA). Dept. of Biology
- OSTI Identifier:
- 7126283
- Report Number(s):
- DOE/ER/60492-4
ON: DE88014136
- DOE Contract Number:
- FG02-86ER60492
- Resource Type:
- Technical Report
- Resource Relation:
- Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 54 ENVIRONMENTAL SCIENCES; 59 BASIC BIOLOGICAL SCIENCES; PHOSPHATASES; BIOCHEMICAL REACTION KINETICS; PHOSPHORUS; SOIL CHEMISTRY; PHOSPHORUS 32; PHYTIC ACID; PLANTS; ROOT ABSORPTION; TRACER TECHNIQUES; TRITIUM COMPOUNDS; TUNDRA; ABSORPTION; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CHEMISTRY; DAYS LIVING RADIOISOTOPES; ELEMENTS; ENZYMES; ESTERASES; ESTERS; HYDROLASES; ISOTOPE APPLICATIONS; ISOTOPES; KINETICS; LABELLED COMPOUNDS; LIGHT NUCLEI; NONMETALS; NUCLEI; ODD-ODD NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC PHOSPHORUS COMPOUNDS; PHOSPHORIC ACID ESTERS; PHOSPHORUS ISOTOPES; RADIOISOTOPES; REACTION KINETICS; UPTAKE; 520101* - Environment, Aquatic- Basic Studies- Radiometric Techniques- (-1989); 550201 - Biochemistry- Tracer Techniques
Citation Formats
Kroehler, C J, and Linkins, A E. Root surface acid phosphatases and their role in phosphorus assimilation by Eriophorum vaginatum. United States: N. p., 1988.
Web.
Kroehler, C J, & Linkins, A E. Root surface acid phosphatases and their role in phosphorus assimilation by Eriophorum vaginatum. United States.
Kroehler, C J, and Linkins, A E. 1988.
"Root surface acid phosphatases and their role in phosphorus assimilation by Eriophorum vaginatum". United States.
@article{osti_7126283,
title = {Root surface acid phosphatases and their role in phosphorus assimilation by Eriophorum vaginatum},
author = {Kroehler, C J and Linkins, A E},
abstractNote = {Eriophorum vaginatum is a dominant plant in much of the arctic tundra ecosystem where phosphorus is frequently a limiting nutrient. The mineralization of this organic phosphorus was thought to be principally controlled by microbial respiration, however, more recent work shows that extracellular soil phosphatases are the principal regulators. The existence of plant root and mycorrhizal surface phosphatases which are capable of hydrolyzing organic phosphorus compounds, suggests that soil organic phosphorus may be directly utilized by plants. Since E. vaginatum is a tussock forming sedge with a very dense annually produced rooting system which can exploit most of the tussock soil volume, its surface phosphatases may play a dominant role in organic phosphorus hydrolysis into inorganic phosphorus. Of equal significance would be the potential for this activity to contribute to the phosphorus nutrition through the coupling of phosphorus hydrolysis on the root and root uptake of the resultant inorganic phosphorus. Phosphatase activity was investigated and found to be uniformly distributed along the surface of the root. Kinetic analysis of the enzyme gave estimates of 9.23 mM for the apparent Km and 1.61 * 10/sup -3/ ..mu..moles mm-2 hr/sup -1/ for the apparent Vmax. Saturation values for E. vaginatum phosphatases are about 3 times higher than average soil solution organic phosphorus concentrations. 12 refs., 4 figs.},
doi = {},
url = {https://www.osti.gov/biblio/7126283},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1988},
month = {Fri Jan 01 00:00:00 EST 1988}
}