![Figure 5. LF head to tail interactions in (PA63)7–(LF)3. (A) The C-terminal domain of LF (1LFC) establishes a large contact with the N-domain of the adjacent LF molecule (2LFN). This interaction (blue circle) is shown in the EM map displayed at two different contour levels (131,000 A3 and 112,000 A3 in A and B, respectively). Two adjacent LFC domains establish a minor interaction (marked by a green arrow) that is broken at the higher threshold (see B). A very similar interaction is observed between 2LFC and 3LFN. (B) Close-up with two atomic models of LF fit into the density. The top of the PA63 heptamer (shown in red) is just visible. The blue circle highlights the novel 1LFC–2LFN interaction with coloration in orange of segments 572–579 of 1LFC and 75–83 of 2LFN. This region is identical in our model for 2LFC–3LFN. The black arrow highlights the position of the α1–β1 segment of 2LFN, which has been modeled in the open conformation (similar to the conformation solved by x-ray crystallography for (PA63)8–(LFN)4 reported in Feld et al. [2010]) and is an identical position for 1LFN and 3LFN.](https://cdn.rupress.org/rup/content_public/journal/jgp/148/4/10.1085_jgp.201611617/5/jgp_201611617_fig5.jpeg?Expires=1773523007&Signature=n~WBYiM0tp1O4rURwIlTbRYO6voSm-FTX6pWEuEniEiP6xPjBTR0HpDos82OD5u9ZP7G8CUDlonhj3B9Cnj6avLGwj8W-hm72Llp67dNRpYP2lOiy5vaxJcII24c9AaVuSSZgOQh9t0KTVQbQimHpQmJ-nbCbE3-ODRiawjada1aFDeYGf7~I9Sv3LvfzQvg-4qdy~8Gqq1U5iRuC~Y~SvCejaCsKkrEGY98Rpkgs8ZoDLsDvMar6Uwj0RMtHc3Mf2Y7vlXUmk5L8JIS6GM2rtPt214vtSNGeq~3uB2hYcbVHh2sDgzbiRaUdwmc71BSJCha99DXNorcJDE38xGNLw__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
LF head to tail interactions in (PA63)7–(LF)3. (A) The C-terminal domain of LF (1LFC) establishes a large contact with the N-domain of the adjacent LF molecule (2LFN). This interaction (blue circle) is shown in the EM map displayed at two different contour levels (131,000 A3 and 112,000 A3 in A and B, respectively). Two adjacent LFC domains establish a minor interaction (marked by a green arrow) that is broken at the higher threshold (see B). A very similar interaction is observed between 2LFC and 3LFN. (B) Close-up with two atomic models of LF fit into the density. The top of the PA63 heptamer (shown in red) is just visible. The blue circle highlights the novel 1LFC–2LFN interaction with coloration in orange of segments 572–579 of 1LFC and 75–83 of 2LFN. This region is identical in our model for 2LFC–3LFN. The black arrow highlights the position of the α1–β1 segment of 2LFN, which has been modeled in the open conformation (similar to the conformation solved by x-ray crystallography for (PA63)8–(LFN)4 reported in Feld et al. [2010]) and is an identical position for 1LFN and 3LFN.
