Affinity to cellulose is a shared property among coiled-coil domains of intermediate filaments and prokaryotic intermediate filament-like proteins

Niklas Söderholm,Isabel Sierra Flores,Klas Flärdh,Ala Javadi,Linda Sandblad

doi:10.1038/s41598-018-34886-7

Niklas Söderholm, Isabel Sierra Flores + Show 3 more

Open Access

https://doi.org/10.1038/s41598-018-34886-7

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Journal: Scientific Reports	Publication Date: Nov 8, 2018
Citations: 7	License type: open-access

Affiliation: Umeå University, Lund University

Abstract

Coiled-coil domains of intermediate filaments (IF) and prokaryotic IF-like proteins enable oligomerisation and filamentation, and no additional function is ascribed to these coiled-coil domains. However, an IF-like protein from Streptomyces reticuli was reported to display cellulose affinity. We demonstrate that cellulose affinity is an intrinsic property of the IF-like proteins FilP and Scy and the coiled-coil protein DivIVA from the genus Streptomyces. Furthermore, IF-like proteins and DivIVA from other prokaryotic species and metazoan IF display cellulose affinity despite having little sequence homology. Cellulose affinity-based purification is utilised to isolate native FilP protein from the whole cell lysate of S. coelicolor. Moreover, cellulose affinity allowed for the isolation of IF and IF-like protein from the whole cell lysate of C. crescentus and a mouse macrophage cell line. The binding to cellulose is mediated by certain combinations of coiled-coil domains, as demornstrated for FilP and lamin. Fusions of target proteins to cellulose-binding coiled-coil domains allowed for cellulose-based protein purification. The data presented show that cellulose affinity is a novel function of certain coiled-coil domains of IF and IF-like proteins from evolutionary diverse species.

Highlights

Numerous species of prokaryotic and eukaryotic origin are predicted to encode coiled-coil intermediate filament (IF) or intermediate filaments (IF)-like proteins[1,2,3,4]
Experimental support for cellulose affinity of FilP orthologues was obtained by performing Avicel affinity purification
We have demonstrated cellulose binding by coiled-coil IF-like, DivIVA and bona fide IF proteins

Summary

Introduction

Numerous species of prokaryotic and eukaryotic origin are predicted to encode coiled-coil intermediate filament (IF) or IF-like proteins[1,2,3,4]. Before FilP was considered as an IF-like protein, a FilP orthologue from Streptomyces reticuli denoted AbpS was discovered to display high affinity to Avicel during a screen for cellulose binding proteins[18]. Avicel affinity purification of recombinant FilP, Scy and DivIVA expressed in E. coli verified that there was a direct protein-cellulose interaction and that cellulose binding was not dependent on Streptomyces-specific posttranslational modifications (Fig. 1d).

Results

Conclusion