Fig 1.

The STM4467 gene is required for ADI activity. (A) Schematic representation of the ADI pathway gene cluster in S. Typhimurium. (B) The ADI activities of the wild-type (WT) strain (14028s), the STM4467 deletion mutant (CH102), strain CH102 carrying plasmid p4467 (ΔSTM4467/p4467), the WT strain carrying plasmid p4463, and strain CH102 carrying plasmid p4463 (ΔSTM4467/p4463) were determined by using cell extracts grown in LB medium. The development of an orange color indicates the ADI-catalyzed production of l-citrulline from l-arginine. (C) Quantification of the ADI activity displayed by the S. Typhimurium strains described for panel B. Means and standard deviations from three independent experiments are shown (**, P < 0.01). OD₄₉₀, optical density at 490 nm.