The Bradyrhizobium japonicum fsrB gene is essential for utilization of structurally diverse ferric siderophores to fulfill its nutritional iron requirement.

ABSTRACT: In Bradyrhizobium japonicum, iron uptake from ferric siderophores involves selective outer membrane proteins and non-selective periplasmic and cytoplasmic membrane components that accommodate numerous structurally diverse siderophores. Free iron traverses the cytoplasmic membrane through the ferrous (Fe²⁺ ) transporter system FeoAB, but the other non-selective components have not been described. Here, we identify fsrB as an iron-regulated gene required for growth on iron chelates of catecholate- and hydroxymate-type siderophores, but not on inorganic iron. Utilization of the non-physiological iron chelator EDDHA as an iron source was also dependent on fsrB. Uptake activities of ⁵⁵ Fe³⁺ bound to ferrioxamine B, ferrichrome or enterobactin were severely dimin

SUBMITTER: Ong A 

PROVIDER: S-EPMC10411499 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature