CHARACTERIZATION OF PHOSPHATASE IN A TERRESTRIAL SOIL STERILIZED WITH AN ELECTRON BEAM

Journal Article · Thu Nov 15 04:00:00 EST 1962 · Enzymologia (Netherlands) Superseded by Mol. Cell. Biochem.

OSTI ID:4694240

Skujins, J J; Braal, L; McLaren, A D

Studies were made on phosphatase inactivation by radiation in soil, in comparison with inactivation of a purified phosphatase of plant origin. Dublin adobe clay loam was irradiated with an electron beam at 5 Mev or gamma irradiation with a Co/sup 60/ source. The soil samples were irradiated with the diectron beam up to 22 x 10/sup 6/ rep and with gamma rays up to 16 x 10/sup 6/ rep doses. The per cent value of the remaining phosphatase activity in soil was based on the activity in soil irradiated with a 5 x 10/sup 6/ rep dose (taken as 100%). Complete sterility was obtained at this dosage. Potato acid phosphatase was irradiated with the electron beam up to a 16 x 10/sup 6/ rep dose. Enzymatic activity of acid phosphatase was determined on the soluble fraction of the commercially available product. There was no significant change in the amount of the soluble protein fraction upon irradiation and the per cent remaining activity was based on the 100% value of nonirradiated enzyme. The inactivation of soil phosphatase activity (k = 0.05) followed the equation ln(A/A/sub 0/) = -KD and required essentially the same radiation dose as the purified potato acid phosphatase (k = 0.06), if irradiated with 5-Mev electrons. The dose required to reduce the initial activity to 37% was 17 Mrep for potato acid phosphatase and 19 Mrep for soil phosphatase activity following a sterilization dose of 5-Mev electrons. The greatest phosphatase activity in Dublin soil was observed to be at around pH 6.0 with a broad optimum between pH = 5.5 and pH = 8.0. It is of interest that the maximum phosphatase activity is that of the natural pH of the soil (pH = 5.8). Soil phosphatase is probably a mixture of enzymes having origin in several kinds of microorganisms. (TCO)

• Research Organization: Univ. of California, Berkeley
• NSA Number: NSA-17-021507
• OSTI ID: 4694240
• Journal Information: Enzymologia (Netherlands) Superseded by Mol. Cell. Biochem., Journal Name: Enzymologia (Netherlands) Superseded by Mol. Cell. Biochem. Vol. Vol: 25; ISSN ENZYA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ACIDITY
BIOCHEMISTRY
BIOLOGY AND MEDICINE
CLAYS
COBALT 60
ELECTRON BEAMS
ENZYMES
GAMMA RADIATION
MICROORGANISMS
PHOSPHATASES
RADIATION DOSES
SOILS
STERILIZATION