Fig. 3: The RcpC β-hairpin, and oligomerization, contribute to the interaction with RcpA.
From: The structure of the Tad pilus alignment complex reveals a periplasmic conduit for pilus extension
A AlphaFold Multimer-generated model of the complex formed by RcpA (green) and RcpC (Yellow). B Expected position error for the structural model shown in (A). Domains of RcpC and RcpA are indicated. The red arrows highlight the interface between RcpCN and the RcpC β-hairpin, which has a distinctive low expected error. C Crystal violet assay to quantify biofilm formation by the P. aeruginosa ΔfliC ΔpilA strain (left), over-expressing the Tad transcription activator PprB (centre), and strain over-expressing PprB but lacking the C-terminal β-hairpin of RcpC (right). Error bars represent mean values ± SEM, n = 16 biological replicates. D Analysis of P. aeruginosa auto-aggregation of the strains shown in (C), confirming that the RcpC β-hairpin is necessary for Tad-mediated cell-cell interaction. Error bars represent mean values ± SEM, n = 5 biological replicates. E Co-purification of RcpC33-303 (top), RcpC33-259 (middle), and RcpC33-233 (bottom) with His-RcpAN (gel on the right), compared to the corresponding purification in the absence of His-RspAN (left gel). A schematic representation of the corresponding RcpC construct is indicated on the left, with the deleted region in orange. The * symbol indicates an impurity present in the co-purified samples. Images shown are representative of three independent repeats.
