Fig 1.

(A and B) Catabolic pathways for arginine and agmatine in L. sakei through the ADI pathway (A) and the AgDI pathway (B), respectively; (C) organization of the arc operon in L. sakei CTC 494 (arcA, arginine deiminase; arcB, ornithine carbamoyltransferase [OTC]; arcC, carbamate kinase [CK]; arcT, putative transaminase; arcD, arginine/ornithine antiporter [A/O]; arcR, regulatory protein); (D) organization of a putative second arc operon or AgDI operon in L. sakei 23 K. The ADI pathway is present in all L. sakei strains, whereas an operational AgDI pathway was present in only 2 of the 29 L. sakei strains tested. PTC, putrescine carbamoyltransferase; Ag/P, agmatine/putrescine antiporter.