the aetiological agent of cholera, possesses multiple iron acquisition systems, including those for the transport of siderophores. How these systems benefit in low-iron, polymicrobial communities in environmental settings or during infection remains poorly understood. Here, we demonstrate that in iron-limiting conditions, co-culture of with a number of individual siderophore-producing microbes significantly promoted growth . We further show that in the host environment with low iron, colonizes better in adult mice in the presence of the siderophore-producing commensal . Taken together, our results suggest that in aquatic reservoirs or during infection, may overcome environmental and host iron restriction by hijacking siderophores from other microbes.