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Yersinia pestis, the pathogen causing plague, requires iron to grow. Y. pestis employs several uptake pathways for iron, including the siderophore yersiniabactin, as well as hemin and inorganic iron. The Y. pestis iron assimilation repertoire further harbors the uncharacterized YiuRABC pathway, presumed to transport an as yet unidentified Fe(III)-siderophore(s). Through intrinsic fluorescence quenching of the periplasmic binding protein YiuA, we discovered that YiuA displays high affinity towards Fe(III) complexes of the hydrolysis products of enterobactin, Fe(III)-[di-(DHB-LSer)] and Fe(III)-[DHB-LSer]2, with Kd‘s of 27.6 ± 4.2 nM and 28.2 ± 6.9 nM, respectively, as well as the bis-catechol siderophore butanochelin, with Kd 0.76 ± 0.17 nM. By comparison, YiuA has a much weaker affinity for intact Fe(III)-enterobactin, Kd 444.7 ± 20.6 nM. Electronic circular dichroism spectroscopy reveals YiuA has a strong preference for binding Λ configured Fe(III)-siderophores, which can be achieved with the Fe(III) bis-catechol complexes but not Fe(III)-enterobactin.
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This content will become publicly available on October 3, 2026
Yersinia ruckeri YRB periplasmic binding protein YiuA selectively recognizes a Fe( iii )-mono-catecholate siderophore
Yersinia ruckeriproduces the tri-catechol siderophore ruckerbactin, Rb, yet its periplasmic binding protein YiuA has unprecedented selectivity for the 1 : 2 Fe(iii) complex of the mono-catechol siderophore, Fe(iii)–(RbMC)2.
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- Award ID(s):
- 2108596
- PAR ID:
- 10643567
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Communications
- ISSN:
- 1359-7345
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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