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BY-NC-ND 3.0 license Open Access Published by De Gruyter Open Access January 20, 2016

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

  • Alberto Barbiroli , Francesco Bonomi , Stefania Iametti and Mauro Marengo
From the journal Peptidomics


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 .


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Received: 2015-7-13
Accepted: 2015-9-27
Published Online: 2016-1-20

© 2015 Alberto Barbiroli et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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