Biosynthesis of the iron-transport compound enterochelin: mutants of Escherichia coli unable to synthesize 2,3-dihydroxybenzoate.

Iron supply to Escherichia coli by synthetic analogs of enterochelin.

Synthetic analogs of enterochelin (enterobactin) were tested for their ability to support the growth of Escherichia coli K-12 under iron-limiting conditions. The cyclic compound MECAM [1,3,5-N.N'; N"-tris-(2,3-dihydroxybenzoyl)-triamino-methylbenzene] and its N-methyl derivative Me3MECAM promoted growth, whereas the 2,3-dihydroxy-5-sulfonyl derivatives MECAMS and Me3MECAMS were inactive. The sa...

Iron transport in Escherichia coli K-12. 2,3-Dihydroxybenzoate-promoted iron uptake.

Iron transport of Escherichia coli K-12: involvement of the colicin B receptor and of a citrate-inducible protein.

It was shown that feuB mutants (defective in ferric enterochelin uptake) were unable to adsorb colicin B. In addition, they were missing one of the three outer-membrane proteins which are over produced in strains grown in iron-deficient, extracted medium. Thus this protein (the feuB protein) is probably the receptor for colicin B and functions in enterochelin-mediated iron transport. The feuB g...

The colicin I receptor of Escherichia coli K-12 has a role in enterochelin-mediated iron transport.

Iron can enter the E coZi K-l 2 cell in four ways. There exist three specific, high affinity systems which transport iron with the aid of either enterochelin [l] , citrate [2] or ferrichrome [3]. The fourth system is a low affinity uptake system for which no such complexing agent has been described [2]. Our knowledge of the membrane components required for high affinity iron transport and for m...

Normal iron-enterochelin uptake in mutants lacking the colicin I outer membrane receptor protein of Escherichia coli.

The outer membranes of two independent colicin Ia-resistant mutants of Escherichia coli K-12 lack the colicin Ia receptor protein. Such mutants exhibit normal capacity for enterochelin (enterobactin)-mediated iron uptake. It is concluded that the colicin Ia receptor is not involved in iron-enterochelin uptake.