Salmonella uses sulfate reductases with unique catalytic activity to promote gut colonization in mice.

Salmonella's unique sulfate reductases with [4Fe-4S] clusters enhance gut colonization and systemic infection in mice, independent of molybdenum cofactors.

• Why it matters: Understanding how Salmonella evades host defenses and sustains infection is crucial for developing targeted treatments, especially since these enzymes support virulence under oxidative stress.
• What they did: The study characterized three extracytoplasmic sulfate reductases—Xsr1A, Xsr2A, and Xsr3A—using infection models in mice and macrophages, revealing their dependence on [4Fe-4S] clusters instead of molybdenum cofactors.
• The result: These enzymes promote Salmonella growth and virulence by counteracting oxidative bursts, and their widespread evolutionary presence suggests a conserved redox mechanism within the MopB superfamily.