Is the production of the biogenic amines tyramine and putrescine a species-level trait in enterococci?

► Tyramine production is a species-level trait of Enterococcus faecalis, Enterococcus faecium and Enterococcus durans. ► The production of putrescine from agmatine is a species-level trait of E. faecalis. ► The production of putrescine from agmatine is a strain-level trait of E. faecium.