An Exposed Outer Membrane Hemin-Binding Protein Facilitates Hemin Transport by a TonB-Dependent Receptor in Riemerella anatipestifer.

ABSTRACT: Iron is an essential element for the replication of most bacteria, including Riemerella anatipestifer, a Gram-negative bacterial pathogen of ducks and other birds. R. anatipestifer utilizes hemoglobin-derived hemin as an iron source; however, the mechanism by which this bacterium acquires hemin from hemoglobin is largely unknown. Here, rhuA disruption was shown to impair iron utilization from duck hemoglobin in R. anatipestifer CH-1. Moreover, the putative lipoprotein RhuA was identified as a surface-exposed, outer membrane hemin-binding protein, but it could not extract hemin from duck hemoglobin. Mutagenesis studies showed that recombinant RhuA^Y144A, RhuA^Y177A, and RhuA^H149A lost hemin-binding ability, suggesting that amino acid sites at tyrosine 1

SUBMITTER: Liu M 

PROVIDER: S-EPMC8276807 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature