Pyrimidine nucleoside phosphorylation in developing seeds and germinating seedlings of wheat

Miscellaneous · Fri Jan 01 00:00:00 EST 1988

OSTI ID:6719360

Rowe, M L

Uridine- and thymidine-phosphorylating enzymes were measured in developing and germinating seeds of Triticum aestivum v. Arthur and T. aestivum v. Lemhi. Because crude extracts were to be used in the developmental study, characteristics of unpurified nucleoside phosphotransferase (NPTase) were examined. In the developmental study with two varieties of wheat, NPTase activity was found to be very low in all of the true seed tissues during seed maturation. Uridine-phosphorylating activity was due to primarily to uridine kinase. Thymidine phosphorylation was very low in all tissues throughout seed maturation, with a brief appearance by thymidine kinase in the developing embryo. In germinating seeds, uridine-phosphorylating activity was present from earliest stages of germination but showed a decrease in activity followed by a recovery after 48 hours inbibition. Experiments using ({alpha}-{sup 32}P)ATP indicated that uridine kinase was present during early germination but had disappeared by 96 hours. Uridine phosphorylation at later stages of germination was accomplished by NTPase. Thymidine phosphorylation did not begin until after 36 hours of germination and was the result of NPTase activity.

• Research Organization: Tennessee Univ., Knoxville, TN (USA)
• OSTI ID: 6719360
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
NUCLEOSIDES
PHOSPHORYLATION
PHOSPHOTRANSFERASES
ENZYME ACTIVITY
WHEAT
GERMINATION
ATP
PHOSPHORUS 32
PYRIMIDINES
SEEDLINGS
TRACER TECHNIQUES
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CEREALS
CHEMICAL REACTIONS
DAYS LIVING RADIOISOTOPES
ENZYMES
GRASS
HETEROCYCLIC COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
LILIOPSIDA
MAGNOLIOPHYTA
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOSPHORUS ISOTOPES
PHOSPHORUS-GROUP TRANSFERASES
PLANTS
RADIOISOTOPES
RIBOSIDES
TRANSFERASES
550201* - Biochemistry- Tracer Techniques