Labile Iron Pool of Isolated Cytosol Likely Includes Fe-ATP and Fe-Citrate but not Fe-Glutathione or Aqueous Fe.

The existence of labile iron pools (LFePs) in biological systems has been recognized for decades, but their chemical composition remains uncertain. Here, the LFeP in cytosol from was investigated. Mössbauer spectra of whole vs lysed cells indicated significant degradation of iron-sulfur clusters (ISCs), even using an unusually gentle lysis procedure; this demonstrated the fragility of ISCs.

Direct Detection of the Labile Nickel Pool in : New Perspectives on Labile Metal Pools.

Nickel serves critical roles in the metabolism of and many prokaryotes. Many details of nickel trafficking are unestablished, but a nonproteinaceous low-molecular-mass (LMM) (LNiP) is thought to be involved. The portion of the cell lysate that flowed through a 3 kDa cutoff membrane, which ought to contain this pool, was analyzed by size-exclusion and hydrophilic interaction chromatographies (SEC and HILIC) with detection by inductively coupled plasma (ICP) and electrospray ionization (ESI) mass spectrometries.

Low-molecular-mass labile metal pools in Escherichia coli: advances using chromatography and mass spectrometry.

Labile low-molecular-mass (LMM) transition metal complexes play essential roles in metal ion trafficking, regulation, and signalling in biological systems, yet their chemical identities remain largely unknown due to their rapid ligand-exchange rates and weak M-L bonds. Here, an Escherichia coli cytosol isolation procedure was developed that was devoid of detergents, strongly coordinating buffers, and EDTA. The interaction of the metal ions from these complexes with a SEC column was minimized by pre-loading the column with ZnSO and then monitoring Zn and other metals by inductively coupled plasma mass spectrometry (ICP-MS) when investigating cytosolic ultrafiltration flow-through-solutions (FTSs).

Chromatographic detection of low-molecular-mass metal complexes in the cytosol of Saccharomyces cerevisiae.

Fluorescence-based chelators are commonly used to probe labile low-molecular-mass (LMM) metal pools in the cytosol of eukaryotic cells, but such chelators destroy the complexes of interest during detection. The objective of this study was to use chromatography to directly detect such complexes. Towards this end, 47 batches of cytosol were isolated from fermenting S.