Fig. 1

Structure of SaPIbov1 Stl domains. a Sequence of SaPIbov1 Stl. The sequence of SaPIbov1 Stl is divided as BovI-Stl^N-ter and BovI-Stl^C-ter corresponding to the fragments used to solve the crystal structures. Structural elements are shown above the sequence coloured as b and c. The latch observed in the BovI-Stl^C-ter structure in complex with ϕO11 Dut is indicated in red. b Cartoon representation of SaPIbov1 Stl^N-ter. Two orthogonal views of the BovI-Stl^N-ter structure are shown and the secondary structural elements are numbered and labelled in order from the N to C terminus. The HTH domain is coloured in magenta and the middle domain in cyan, with the connecting α5 helix in green. c Structure of SaPIbov1 Stl^C-ter. Cartoon representation of the BovI-Stl^C-ter dimer with protomers coloured in blue and orange, respectively. Two orthogonal views are shown and the secondary structural elements are labelled following the numbering of BovI-Stl^N-ter (the asterisk indicates elements from the second protomer)