%0 Journal Article
%A Baranova, E.
%A Fronzes, R.
%A Garcia-Pino, A.
%A Van Gerven, N.
%A Papapostolou, D.
%A Pehau-Arnaudet, G.
%A Pardon, E.
%A Steyaert, J.
%A Howorka, S.
%A Remaut, H.
%A DESY
%T SbsB structure and lattice reconstruction unveil Ca<sup>2<sup>+</sup></sup> triggered S-layer assembly
%J Nature 
%V 487
%@ 0028-0836
%C London [u.a.]
%I Nature Publ. Group
%M PHPPUBDB-25515
%P 119 - 122
%D 2012
%X S-layers are regular two-dimensional semipermeable protein layers that constitute a major cell-wall component in archaea and many bacteria. The nanoscale repeat structure of the S-layer lattices and their self-assembly from S-layer proteins (SLPs) have sparked interest in their use as patterning and display scaffolds for a range of nano-biotechnological applications. Despite their biological abundance and the technological interest in them, structural information about SLPs is limited to truncated and assembly-negative proteins. Here we report the X-ray structure of the SbsB SLP of Geobacillus stearothermophilus PV72/p2 by the use of nanobody-aided crystallization. SbsB consists of a seven-domain protein, formed by an amino-terminal cell-wall attachment domain and six consecutive immunoglobulin-like domains, that organize into a φ-shaped disk-like monomeric crystallization unit stabilized by interdomain Ca(2+) ion coordination. A Ca(2+)-dependent switch to the condensed SbsB quaternary structure pre-positions intermolecular contact zones and renders the protein competent for S-layer assembly. On the basis of crystal packing, chemical crosslinking data and cryo-electron microscopy projections, we present a model for the molecular organization of this SLP into a porous protein sheet inside the S-layer. The SbsB lattice represents a previously undescribed structural model for protein assemblies and may advance our understanding of SLP physiology and self-assembly, as well as the rational design of engineered higher-order structures for biotechnology.
%K Bacterial Proteins: chemistry
%K Bacterial Proteins: metabolism
%K Calcium: chemistry
%K Calcium: metabolism
%K Calcium: pharmacology
%K Cryoelectron Microscopy
%K Crystallization: methods
%K Crystallography, X-Ray
%K Geobacillus stearothermophilus: chemistry
%K Immunoglobulins: chemistry
%K Membrane Proteins: chemistry
%K Membrane Proteins: metabolism
%K Models, Molecular
%K Molecular Dynamics Simulation
%K Nanostructures: chemistry
%K Polymerization: drug effects
%K Protein Structure, Quaternary: drug effects
%K Protein Structure, Tertiary: drug effects
%K Solutions
%K Bacterial Proteins (NLM Chemicals)
%K Immunoglobulins (NLM Chemicals)
%K Membrane Proteins (NLM Chemicals)
%K SbsB protein, Bacillus stearothermophilus (NLM Chemicals)
%K Solutions (NLM Chemicals)
%K Calcium (NLM Chemicals)
%F PUB:(DE-HGF)16
%9 Journal Article
%$ pmid:22722836
%U <Go to ISI:>//WOS:000305982900062
%R 10.1038/nature11155
%U https://bib-pubdb1.desy.de/record/142539