Nanobody Mediated Crystallization of an Archeal Mechanosensitive Channel
2013 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 8, no 10, e77984- p.Article in journal (Refereed) Published
Mechanosensitive channels (MS) are integral membrane proteins and allow bacteria to survive sudden changes in external osmolarity due to transient opening of their pores. The efflux of cytoplasmic osmolytes reduces the membrane tension and prevents membrane rupture. Therefore these channels serve as emergency valves when experiencing significant environmental stress. The preparation of high quality crystals of integral membrane proteins is a major bottleneck for structure determination by X-ray crystallography. Crystallization chaperones based on various protein scaffolds have emerged as promising tool to increase the crystallization probability of a selected target protein. So far archeal mechanosensitive channels of small conductance have resisted crystallization in our hands. To structurally analyse these channels, we selected nanobodies against an archeal MS channel after immunization of a llama with recombinant expressed, detergent solubilized and purified protein. Here we present the characterization of 23 different binders regarding their interaction with the channel protein using analytical gel filtration, western blotting and surface plasmon resonance. Selected nanobodies bound the target with affinities in the pico- to nanomolar range and some binders had a profound effect on the crystallization of the MS channel. Together with previous data we show that nanobodies are a versatile and valuable tool in structural biology by widening the crystallization space for highly challenging proteins, protein complexes and integral membrane proteins.
Place, publisher, year, edition, pages
2013. Vol. 8, no 10, e77984- p.
Green Fluorescent Protein, Size-Exclusion Chromatography, Integral Membrane-Proteins, Heavy-Chain Antibodies, Escherichia-Coli, Crystal-Structure, Angstrom Resolution, Binding-Proteins, Molecular-Basis, Cytochrome-C
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-134567DOI: 10.1371/journal.pone.0077984ISI: 000326032600057ScopusID: 2-s2.0-84886913778OAI: oai:DiVA.org:kth-134567DiVA: diva2:667620
FunderSwedish Research CouncilSwedish Cancer Society
QC 201311272013-11-272013-11-252013-11-27Bibliographically approved