The association and aggregation of the metamorphic chemokine lymphotactin with fondaparinux: from nm molecular complexes to μm molecular assemblies.

Sophie R Harvey,Cait E Macphee,Brian F Volkman,Perdita E Barran

doi:10.1039/c5cc05801e

Abstract

Transmission electron microscopy, mass spectrometry, and drift tube ion mobility-mass spectrometry are used to study the assemblies formed by the metamorphic chemokine lymphotactin in the presence of a model pentameric glycosaminoglycan, fondaparinux. This combination of techniques delineates significant differences in the complexes observed for two forms of the full length protein as well as a truncated form, without the intrinsically disordered C-terminal tail, over a length scale from few nm to μm assemblies.

Highlights

Transmission electron microscopy, mass spectrometry, and drift tube ion mobility-mass spectrometry are used to study the assemblies formed by the metamorphic chemokine lymphotactin in the presence of a model pentameric glycosaminoglycan, fondaparinux
The resulting aggregation is deemed essential and thought to help over-come issues associated with vascular flow.[10]. Despite this to-date, to the best of our knowledge, there have been no reports of using transmission electron microscopy (TEM), as a biophysical technique, to study the aggregation of chemokines occurring in the presence of GAGs in vitro
Given the differences between the full length (WT and CC3) and truncated (WT 1–72) constructs, both in MS and with respect to the aggregate morphologies we considered the conformation of the Ltn:Fx complexes using DT IM-MS

Summary

Introduction

Transmission electron microscopy, mass spectrometry, and drift tube ion mobility-mass spectrometry are used to study the assemblies formed by the metamorphic chemokine lymphotactin in the presence of a model pentameric glycosaminoglycan, fondaparinux. Fx shows only limited signs of aggregation in the absence of Ltn (Fig. S1, ESI†) highlighting that this aggregation is due to the presence, and interactions, of both Ltn and Fx. a School of Chemistry, University of Edinburgh, West Mains Road, EH8 3JJ, Edinburg, UK

Results

Conclusion