Open AccessRoles of the EnvZ/OmpR Two-Component System and Porins in Iron Acquisition in Escherichia coli
Author(s) -
Henri Gerken,
Phu Vuong,
Ketaki Soparkar,
Rajeev Misra
Publication year - 2020
Publication title -
mbio
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.562
H-Index - 121
eISSN - 2161-2129
pISSN - 2150-7511
DOI - 10.1128/mbio.01192-20
Subject(s) - regulon , bacterial outer membrane , ferrous , escherichia coli , porin , mutant , repressor , biochemistry , biology , derepression , microbiology and biotechnology , chemistry , gene , gene expression , psychological repression , organic chemistry
The work presented here solved a long-standing paradox of the negative effects of certain missense alleles of envZ , which codes for kinase of the EnvZ/OmpR two-component system, on the expression of ferric uptake genes. The data revealed that the constitutive envZ alleles activate the Feo- and OmpC-mediated ferrous uptake pathway to flood the cytoplasm with accessible ferrous iron. This activates the ferric uptake regulator, Fur, which inhibits ferric uptake system but cannot inhibit the feo operon due to the positive effect of activated EnvZ/OmpR. The data also revealed the importance of porins in iron homeostasis.