N-PilO2_Bp protein.

<p><b>A.</b> Overall fold of N-PilO2_Bp composed of two α/β topology subdomains, each displaying a mixed β-sheet, separated by a (central) cleft. The bound phosphate ion is shown as spheres. <b>B.</b> Topology diagram of N-PilO2_Bp. This diagram was generated using PDBSum server (<a href="http://www.ebi.ac.uk/pdbsum/" target="_blank">www.ebi.ac.uk/pdbsum/</a>) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0094981#pone.0094981-Laskowski2" target="_blank">[52]</a>. <b>C</b>. Crystal packing of the phosphate-containing N-PilO2_Bp structure, showing the three crystal packing dimers formed by alternative interactions between four symmetry-related monomers (green, blue, magenta and black). The three interfaces are highlighted by black, blue and red shading. The first ‘dimer’, is formed by the interaction between the green (or blue) and the magenta (or black) monomers and the light green (or light blue) phosphate. The second crystallographic dimer occurs between the magenta and black monomers. The third dimer is formed by the green and blue monomers. <b>D</b>. Stereo view of the electron density map for the residues building the phosphate ion binding pocket. The phosphate ion is shown as sphere; the electron density is contoured at 1.5 sigma level. <b>E.</b> Front and back view of N-PilO2_Bp electrostatic surface potential. The electrostatic potential was calculated using the CCP4MG viewer. Negative (red) and positive (blue) charges, and uncharged (white) surfaces are shown. <b>F.</b> Superposition of the 3D structures of N-PilO2_Bp (cyan; PDB codes 4BYZ and 4BZ0) and N-BfpC (chocolate; PDB code 3VHJ).</p

Crystallographic data-collection statistics.

a<p>Data completeness treats Bijvoët mates independently.</p>b<p>Statistics for the highest resolution shells are given in parentheses.</p>c<p><i>R</i>_merge = ∑<i>_hkl</i>∑<i>_i</i>|<i>I(hkl)_I</i> − < <i>I(hkl)</i> >|/∑<i>_hkl</i>∑<i>_i</i>< <i>I(hkl)_i</i> >.</p>d<p>Substructure determination parameters are from ShelxD.</p>e<p>CC  =  [∑<i>wE_oE</i>_c∑<i>w</i> - ∑<i>wE_o</i>∑<i>wE_c</i>]/{[∑<i>w</i>E_o²∑<i>w -</i> (∑<i>w</i>E_o)²] [∑<i>w</i>E_c²∑<i>w</i> -(∑<i>w</i>E_c)²]}^1/2,</p><p>where <i>w</i> is weight. CC_all/CC_weak is the correlation coefficient for all and weak reflections of the best solution.</p>f<p>FOM, figure of merit  =  | <i>F</i>(<i>hkl</i>)best|/|<i>F</i>(<i>hkl</i>)|; <b>F</b>(<i>hkl</i>)best  =  ∑<i>P</i>(α)<b>F</b>_hkl(α)/∑<i>P</i>(α).</p

Comparison of Tfpb machinery R64 thin pilus variant encoding operons for different microorganisms.

<p>The alignment was performed using tblastx from the Blast suite, and visualized in Artemis Comparison Tool. Conserved protein regions are paired by color-shaded regions; the blue and red colors represent the reverse and forward matches, respectively, and color intensity is proportional to the sequence homology. Genes are represented by arrows; the same arrow color indicates putative orthologs. The grey arrows represent genes lacking homologs among represented <i>pil</i> clusters. The <i>pil</i> cluster sequences were retrieved from GenBank: <i>Tfp7</i> locus from <i>B. pseudomallei</i> (<i>Bp</i>) chromosome 2 complete sequence, BX571966.1; PAPI-1 <i>pil</i> gene cluster from <i>P. aeruginosa</i> (<i>Pa</i>) PA14, AY273869.1; R64 transfer region, AB027308.1; and <i>pil</i> operon from <i>Salmonella enterica</i> (<i>Se</i>) subsp. <i>enterica</i> serovar Paratyphi C strain CN13/87, AY249242.1.</p

<i>S. maltophilia</i> adhesion to HeLa cells.

<p>Percentage of bacteria adhered to HeLa cells after 120 min of incubation in 24-well plates. The data correspond to the mean and standard deviation of three different assays carried out in triplicate. ***, <i>p</i>≤0.001 significance of difference with ATCC13637 by unpaired <i>t</i>-test with Welch correction for unequal variances.</p

Neighbor-joining radiation tree based on the concatenated sequences of the MLST loci, showing relationships among the three recent clinical isolates (solid circles), the ATCC13637 strain and 35 previously characterized <i>S. maltophilia</i> pathogenic strains [28].

<p>Previously defined genomic groups <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067207#pone.0067207-Kaiser1" target="_blank">[28]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0067207#pone.0067207-Hauben1" target="_blank">[29]</a> are indicated (#1 to #7, C and D).</p

<i>S. maltophilia</i> serum-sensitivity assay.

<p>Percentage of surviving cells after 90 minutes of incubation in the presence of Hank’s balanced salt solution, human serum or inactivated serum. The values represent the mean of three replicas of the three independent experiments. **, <i>p</i>≤0.01; ***, <i>p</i>≤0.0001 significance of difference with ATCC13637 by unpaired <i>t</i>-test with Welch correction for unequal variances.</p

MICs for several antibiotics against the <i>S. maltophilia</i> collection and clinical strains.

<p>Tc, tetracycline; Mino, minocycline; Gent, gentamicin; Kan, kanamycin; Trim, trimethoprim; Sul, sulphamethoxazole; Cipro, ciprofloxacin; Nor, norfloxacine; Levo, levofloxacin; Ery, erythromycin; Cm, chloramphenicol.</p

Swimming, twitching and biofilm formation of the <i>S. maltophilia</i> collection and clinical strains.

a<p>Values represent the mean and standard deviation.</p>b<p><i>p</i>≤0.001 significance of difference with ATCC13637 by one-way analysis of variance (ANOVA) with a Bonferroni’s multiple comparison post-test.</p

Survival curves of adult zebrafish injected with <i>S. maltophilia</i> ATCC13637, E77, M30, UV74 (10⁸ cfu in 20 µl).

<p>Control groups injected with heat-inactivated UV74 (10⁸ cfu in 20 µl) and sterile PBS (20 µl) presented no mortality (not shown). Zebrafish mortalities were recorded for 168 h post-infection (hpi) and survival curves analyzed using the Kaplan-Meier method (log-rank test: ***, <i>p</i>≤0.001; **, <i>p</i>≤0.01).</p

Molecular mAbs/BP-2a 515 variant docking reveals two different binding orientations.

<p>(A) Ribbon representation of mAb 17C4/A3-BP-2a 515 variant complex. (B) Ribbon representation of mAb 4H11/B7-BP-2a 515 variant complex. In both complexes, the binding interface is CPK represented and colored according to the mAbs and antigen overall structure.</p