# CHEMISTRY OF MICROBIAL IRON TRANSPORT COMPOUNDS

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA BERKELEY · 1989 · $150,214

## Abstract

Microbial iron transport and mobilization is achieved using very powerful
low-molecular-weight complexing agents which solubilize ferric ion through
the formation of pseudo-octahedral complexes of high-spin Fe3+.  These
compounds, called siderophores, are manufactured by microorganisms
specifically in response to their need for iron, an essential element for
growth.  The availability of iron to pathogens has been directly linked to
the onset of disease in a number of illnesses associated with microbial
infection.  Transport of the iron occurs via several different mechanisms,
as found either between different microorganisms or as parallel systems
within one microorganism.  We continue to use the replacement of
kinetically labile Fe(III) by kinetically inert ions such as Cr(III) or
Rh(III) in order to produce metal siderophore complexes of known and stable
geometry to be used as biological probes of the transport process.
Similarly, use of Ga(III) as a substitute for Fe(III) produces complexes of
approximately the same thermodynamic stability and kinetic lability, but of
dramatically different redox behavior.  Thus Ga(III) substituted compounds
can be used as specific probes for parts of the transport and uptake
process which depend upon redox behavior.  The synthesis of chelating
agents which at least in part mimic particular siderophores can be designed
so as to test for which parts of the siderophore are critical in the
recognition process associated with microbial receptor proteins.  Finally,
the fundamental coordination chemistry and solution thermodynamic and
ligand exchange behavior of the siderophores and their analogs will
continue to be characterized as fundamental aspects of the biochemistry of
this important class of compounds.  In particular, the ligand exchange
kinetics in non-aqueous media approximating the hydrophobic environment of
the cell membrane will be examined for any significant difference from the
aqueous ligand exchange behavior.

## Key facts

- **NIH application ID:** 3125021
- **Project number:** 5R01AI011744-15
- **Recipient organization:** UNIVERSITY OF CALIFORNIA BERKELEY
- **SAM.gov UEI:** GS3YEVSS12N6
- **Principal Investigator:** KENNETH N RAYMOND
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1989
- **Award amount:** $150,214
- **Award type:** 5
- **Project period:** 1976-04-01 → 1991-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3125021

## Citation

> US National Institutes of Health, RePORTER application 3125021, CHEMISTRY OF MICROBIAL IRON TRANSPORT COMPOUNDS (5R01AI011744-15). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3125021. Licensed CC0.

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