. The endproducts
of this pathway are either ß-alanine or ßaminoisobutyrate
depending upon whether uracil or
thymine are catabolised by this pathway. In both cases,
NH3 and CO2 are released as byproducts. Uracil catabolism,
may be an important source of ß-alanine, a precursor
for the pantothenate moiety of coenzyme A . Since cytosine is not the substrate
of this pyrimidine reductive pathway and plants lack
cytosine deaminase, catabolism of cytosine nucleotides
may proceed via uridine.