Stabilization of the “open” conformer of apoIscU
on the surface of polystyrene nanobeads
accelerates assembly of a 2Fe2S structure

• Authors: Alberto Barbiroli , Francesco Bonomi , Stefania Iametti , Mauro Marengo
• Languages of publication: EN

Abstracts

EN

The scaffold protein IscU is involved in the
assembly/transfer of FeS clusters. IscU exists in both
open and closed conformation. The clusterless open
conformation of IscU adheres to the hydrophobic
surface of polystyrene nanobeads, as observed for other
proteins. Increased accessibility of the ligand cysteines
in bound IscU facilitates assembly of a 2Fe2S cluster,
and the cluster-bearing structured form of IscU does not
interact with the nanobeads, thus ensuring turnover.
The dependence of accelerated cluster assembly on the
nanobeads concentration pointed to steric and crowding
effects as for promoting cluster formation, and confirms
the requirement for structural flexibility of IscU .

• Publisher: De Gruyter Open
• Journal: Peptidomics
• Year: 2015
• Volume: 2
• Issue: 1

Dates

received

13 - 7 - 2015

online

20 - 1 - 2016

accepted

27 - 9 - 2015

Contributors

author

Alberto Barbiroli

• Section of
  Chemical and Biomolecular Sciences, DeFENS, University of Milan

author

Francesco Bonomi

• Section of
  Chemical and Biomolecular Sciences, DeFENS, University of Milan

author

Stefania Iametti

• DeFENS, University of
  Milan, Via Celoria 2, 20133, Milan, Italy

author

Mauro Marengo

• Section of
  Chemical and Biomolecular Sciences, DeFENS, University of Milan

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Identifiers

DOI

10.1515/ped-2015-0006