GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:24196966

From GONUTS
Jump to: navigation, search
Citation

'Singh, H, Dai, Y, Outten, FW and Busenlehner, LS (2013) Escherichia coli SufE Sulfur Transfer Protein Modulates the SufS Cysteine Desulfurase through Allosteric Conformational Dynamics. J. Biol. Chem. '

Abstract

Iron-sulfur (Fe-S) clusters are critical metallocofactors required for cell function. Fe-S cluster biogenesis is carried out by assembly machinery consisting of multiple proteins. Fe-S cluster biogenesis proteins work together to mobilize sulfide and iron, form the nascent cluster, traffic the cluster to target metalloproteins, and regulate the assembly machinery in response to cellular Fe-S cluster demand. A complex series of protein-protein interactions is required for the assembly machinery to function properly. Despite considerable progress in obtaining static three-dimensional structures of the assembly proteins, little is known about transient protein-protein interactions during cluster assembly or the role of protein dynamics in the cluster assembly process. The Escherichia coli cysteine desulfurase SufS (EC 2.8.1.7) and its accessory protein SufE work together to mobilize persulfide from L-cysteine, which is then donated to the SufB Fe-S cluster scaffold. Here we use amide hydrogen/deuterium exchange mass spectrometry (HDX-MS) to characterize SufS-SufE interactions and protein dynamics in solution. HDX-MS analysis shows that SufE binds near the SufS active site to accept persulfide from Cys364. Furthermore, SufE binding initiates allosteric changes in other parts of the SufS structure that likely affect SufS catalysis and alter SufS monomer-monomer interactions. SufE enhances the initial L-cysteine substrate binding to SufS and formation of the external aldimine with pyridoxal phosphate required for early steps in SufS catalysis. Together, these results provide a new picture of the SufS-SufE sulfur transferase pathway and suggest a more active role for SufE in promoting the SufS cysteine desulfurase reaction for Fe-S cluster assembly.

Links

PubMed Online version:10.1074/jbc.M113.525709

Keywords


Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

ECOLI:SUFE

GO:0097361: CIA complex

ECO:0000314:

C

Figure 3. SufS-SufE complex formation.

complete
CACAO 9166

See also

References

See Help:References for how to manage references in GONUTS.