TraN directs surface exclusion specificity.

<p><i>E</i>. <i>coli</i> GG56 (Nx<sup>r</sup>) containing pVCR94<sup>Sp</sup> Δ<i>traN</i> and expressing the indicated <i>traN</i> variants from pBAD30 (Ap<sup>r</sup>) served as the donor, and <i>E</i>. <i>coli</i> CAG18439 (Tc<sup>r</sup>) expressing the indicated <i>sfx</i> variants from a single-copy, chromosomally integrated pAH56 (Kn<sup>r</sup>) was used as the recipient. Transconjugants containing pVCR94<sup>Sp</sup> Δ<i>traN</i> were selected as the Tc<sup>r</sup> Sp<sup>r</sup> colonies. Crossbars show the mean and standard error of the mean of three independent experiments. One-way ANOVA (<i>traN</i> pVCR94, p = 2.21e-8; <i>traN</i> pAsa4c, p = 4.84e-10; <i>traN</i> pAhD4-1, p = 2.20e-8; <i>traN</i> pAQU1, p = 1.81e-9) with a Tukey-Kramer post-test was used on the log<sub>10</sub>-transformed values to compare the means. Exclusion indices, shown at the bottom of each crossbar, are calculated by dividing the frequency of transfer of pVCR94<sup>Sp</sup> Δ<i>traN</i> to the empty recipient divided by the transfer frequency to the recipient expressing the indicated <i>sfx</i> variant. Statistical significance (<a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1011442#pgen.1011442.s010" target="_blank">S2 File</a>) is shown as a compact letter display for pairwise comparisons where means grouped under identical letters are not statistically different.</p> <p>(PDF)</p>