Location of mutations in FHbp in relation to FH.

<p><b>A.</b> Plot of distance between each FHbp residue and closest atom in FH in the crystal structure of the FHbp-FH complex (PDB ID 2W80) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0128185#pone.0128185.ref023" target="_blank">23</a>]. Distances greater than 6 Å are depicted as 12 Å. The lipidated Cys residue in the mature protein is designated as residue number 1. <b>B.</b> Histogram showing number of mutations at each residue position in FHbp. Above the histogram are the known FH interaction residues (filled circles) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0128185#pone.0128185.ref023" target="_blank">23</a>], residues mutated in previous studies (open circles) [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0128185#pone.0128185.ref022" target="_blank">22</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0128185#pone.0128185.ref023" target="_blank">23</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0128185#pone.0128185.ref027" target="_blank">27</a>] and residues mutated in the present study (filled stars). <b>C.</b> Location of residues with mutations identified to decrease binding of FH to FHbp (magenta). The location of residue R41, which previously was identified as an important FH binding residue is shown in yellow. <b>D.</b> Location of FH fragment (grey) relative to residues with mutations identified to decrease binding of FH to FHbp.