GO:0009446

putrescine biosynthetic process

Details: 
The chemical reactions and pathways resulting in the formation of putrescine, 1,4-diaminobutane; putrescine can be synthesized from arginine or ornithine and is the metabolic precursor of spermidine and spermine. [GOC:go_curators, ISBN:0198506732]
Evidence Code: 
IEA