Mimicking salmochelin S1 and the interactions of its Fe(III) complex with periplasmic iron siderophore binding proteins CeuE and VctP

TY - JOUR

T1 - Mimicking salmochelin S1 and the interactions of its Fe(III) complex with periplasmic iron siderophore binding proteins CeuE and VctP

AU - Wilde, Ellis J

AU - Blagova, Elena V

AU - Sanderson, Thomas J

AU - Raines, Daniel J

AU - Thomas, Ross P

AU - Routledge, Anne

AU - Duhme-Klair, Anne-Kathrin

AU - Wilson, Keith S

N1 - © 2018 Elsevier Inc. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy.

PY - 2019/1

Y1 - 2019/1

N2 - A mimic of the tetradentate stealth siderophore salmochelin S1, was synthesised, characterised and shown to form Fe(III) complexes with ligand-to-metal ratios of 1:1 and 3:2. Circular dichroism spectroscopy confirmed that the periplasmic binding proteins CeuE and VctP of Campylobacter jejuni and Vibrio cholerae, respectively, bind the Fe(III) complex of the salmochelin mimic by preferentially selecting Λ-configured Fe(III) complexes. Intrinsic fluorescence quenching studies revealed that VctP binds Fe(III) complexes of the mimic and structurally-related catecholate ligands, such as enterobactin, bis(2, 3-dihydroxybenzoyl-l-serine) and bis(2, 3-dihydroxybenzoyl)-1, 5-pentanediamine with higher affinity than does CeuE. Both CeuE and VctP display a clear preference for the tetradentate bis(catecholates) over the tris(catecholate) siderophore enterobactin. These findings are consistent with reports that V. cholerae and C. jejuni utilise the enterobactin hydrolysis product bis(2, 3-dihydroxybenzoyl)-O-seryl serine for the acquisition of Fe(III) and suggest that the role of salmochelin S1 in the iron uptake of enteric pathogens merits further investigation.

AB - A mimic of the tetradentate stealth siderophore salmochelin S1, was synthesised, characterised and shown to form Fe(III) complexes with ligand-to-metal ratios of 1:1 and 3:2. Circular dichroism spectroscopy confirmed that the periplasmic binding proteins CeuE and VctP of Campylobacter jejuni and Vibrio cholerae, respectively, bind the Fe(III) complex of the salmochelin mimic by preferentially selecting Λ-configured Fe(III) complexes. Intrinsic fluorescence quenching studies revealed that VctP binds Fe(III) complexes of the mimic and structurally-related catecholate ligands, such as enterobactin, bis(2, 3-dihydroxybenzoyl-l-serine) and bis(2, 3-dihydroxybenzoyl)-1, 5-pentanediamine with higher affinity than does CeuE. Both CeuE and VctP display a clear preference for the tetradentate bis(catecholates) over the tris(catecholate) siderophore enterobactin. These findings are consistent with reports that V. cholerae and C. jejuni utilise the enterobactin hydrolysis product bis(2, 3-dihydroxybenzoyl)-O-seryl serine for the acquisition of Fe(III) and suggest that the role of salmochelin S1 in the iron uptake of enteric pathogens merits further investigation.

U2 - 10.1016/j.jinorgbio.2018.10.008

DO - 10.1016/j.jinorgbio.2018.10.008

M3 - Article

C2 - 30384009

SN - 0162-0134

VL - 190

SP - 75

EP - 84

JO - JOURNAL OF INORGANIC BIOCHEMISTRY

JF - JOURNAL OF INORGANIC BIOCHEMISTRY

ER -