spermine , not normally present in control cells , increased to detectable , low levels ( less than 1 nmol mg-1 protein ) after 36 h treatment . alpha-dl-difluoromethylornithine-treated cells were unable to synthesize putrescine from [ 3h ] ornithine but were able to convert [ 3h ] putrescine + methionine to spermidine .
C0002260
alpha
C0029277
ornithine