Activity of enzymes involved in pyrimidine metabolism in the germinating wheat grains

• Published in: Phytochemistry (Oxford) Vol. 11; no. 1; pp. 77 - 82
• Main Authors: Mazuś, Barbara, Buchowicz, Jerzy
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1972
• Subjects: pyrimidine metabolism; changes in enzyme activity; germinating wheat seed; wheat; Gramineae; Triticum aestivum
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/S0031-9422(00)89970-7

Activities of carbamoyl phosphate synthetase, aspartate carbamoyltransferase, dihydro-orotase, dihydro-pyrimidinase, uracil phosphoribosyltransferase, uridine phosphorylase, uridine kinase and acid phosphatase were measured in extracts from wheat grains germinated for periods ranging from 0 to 48 hr. With the exception of uridine phosphorylase which appeared only 24 hr after initiation of germination, all these activities were detected in the dry grains. Activities concerned with the synthesis of pyrimidine ring de novo dropped at the onset of germination (0·5–2 hr) and increased thereafter gradually. Activities involved in the degradative pathway were maintained at a roughly constant level during the first 24 hr and rose considerably later on. The results are discussed in relation to the sequence of initiation of RNA and protein synthesis during seed germination.