Template:Team:Bonn:NetworkData

content.text= "<div class='content-image'><img src='https://static.igem.org/mediawiki/2013/thumb/4/42/Bonn_OutlookCCSspB1_Version2.png/726px-Bonn_OutlookCCSspB1_Version2.png'>sspB structure and its conservation among C. crescentus, E. coli and H. influenzae ^{<a href='[42.1]'>[42.1]</a>}</div>The sspB&alpha; dimeric structure is stabilized by two &alpha;-helices in interaction, as part B of the figure above shows, each of them located at the N-terminus of either sspB&alpha; molecule. The subsequent parts of the protein form a domain consisting of two &beta;-sheet structures, together building up the ssrA binding site. An unstructured area at the C-terminus being referred to as the XB module forms the ClpX binding part of the protein. It is connected to the rest of the molecule via a linker domain. ^{<a href='[42.2]'>[42.2]</a>} </br>Chien et al. ^{<a href='[42.1]'>[42.1]</a>} compared crystal structures of C. crescentus sspB&alpha; and its E. coli and H. influenzae sspB orthologs, discovering that in sspB&alpha; the &alpha;-helices are significantly longer, more twisted and cover a larger cross section area than the other two sspB orthologs. Also considering that &beta;-sheets are rotated by around 20&deg; in comparison to E. coli and H. influenzae orthologs, this leads to an antiparallel orientation of the two ssrA tagged protein bound to the ssrA binding sites of an sspB&alpha; dimer in C. crescentus, while they are parallel in &gamma;-protobacterial sspB.</br></br><div class='content-image'><img src='https://static.igem.org/mediawiki/2013/6/6c/Bonn_OutlookCCSspB2.png' align=left>By measuring GFP fluorescence intensity, decrease of GFP-^CCssrA concentration (1) without sspB&alpha; added, (2) with mutated sspB&alpha;(Q74A) added , (3) with wildtype sspB&alpha; added can be visualized. ^{<a href='[42.1]'>[42.1]</a>}</div>Chien et al. point out that although there are the remarkable differences in protein structure between sspB&alpha; and its &gamma;-protobacterial ortholog, they show up with similar effectiveness in binding proteins tagged with the related ssrA peptide. But it turned out in their research that effectiveness of sspB&alpha; binding to the protein which needs to be tethered to the ClpXP protease strongly depends on which ssrA ortholog the protein is tagged with. sspB&alpha; binds firmly to ^CCssrA, with an affinity being 175 times as large as for binding to ^ECssrA (i.e. the E. coli ortholog). By comparing the crystal structures of both sspB&alpha; and the compound of sspB&alpha; and ^CCssrA, Chien et al. further proved that binding of sspB&alpha; to ^CCssrA does not lead to significant changes of its 3D conformation.</br></br><h2>References</h2></br><a href='[42.1]'>[42.1]</a> <a href='http://www.ncbi.nlm.nih.gov/pubmed/17937918'>Structure and substrate specificity of an SspB ortholog: design implications for AAA+ adaptors, Chien et al., Cell Press, 2007, PMID: 17937918</a></br><a href='[42.2]'>[42.2]</a><a href='http://www.ncbi.nlm.nih.gov/pubmed/14967151'> Bivalent tethering of sspB to ClpXP is required for efficient substrate delivery: a protein design study, Bolon DN et al., Mol Cell, 2004, PMID: 14967151</a>"; *References-Ueberschrift muss an Format des Bildes angepasst werden