A putative siderophore receptor of 12656-12 under Fur control also binds hemoglobin.

family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although expresses different virulence factors, its response to growth under iron restriction is unknown. cultured in the presence of 2,2'-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in 12656-12 mutant (Ω 126.13) grown in the presence or not of 2,2'-dipyridyl. The addition of FeCl to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω 126.13 strain was not affected and biofilm production increased in 35%. Ω 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as .