However, when iron is readily available, either from freely diffusing in environment or another bacterium's siderophores, P. fluorescens ceases production, allowing the bacterium to devote its energy towards growth. One study showed that when P. fluorescens grew in association with Streptomyces ambofaciens, another bacterium that produces the siderophore coelichen, no pyoverdine was detected. This result suggested that P. fluorescens ceased siderophore production in favor of taking up iron-bound coelichen, an association also known as siderophore piracy.[23]