Fig. 7: Mechanical features of C1 at a basic pH of 9.0 and in the presence of EDTA (10 mM).
From: An ester bond underlies the mechanical strength of a pathogen surface protein
a Representative force–extension curves of the “Ester bond unruptured” group. The traces show only four GB1 unfolding events without the signature of C1 unfolding or ester bond rupture. b Representative force–extension curves of the “Ester bond ruptured” group. Two populations of unfolding events were observed: Four peaks with a ΔLc of 41 nm relate to GB1 unfolding and an additional one with a ΔLc of 41 nm corresponds to the rupture of the ester bond. c Representative force–extension curves of the “Protein fully unfolded” group. Except for the four GB1 unfolding events, there is an additional peak with ΔLc of 47 nm (colored in red, upper trace) or a spacer corresponding to the unfolded of C1 (lower trace). d The statistics of the three types of events of C1 at pH 7.4 and pH 9.0 and in the presence of EDTA (pH 7.4). The numbers of tests in three conditions are 3, 3, 3 for pH 7.4, pH 7.4 with EDTA and pH 9, respectively. Error bars represent SD. e Proposed mechanism for the function of ester bond containing proteins during bacteria invasion. This experiment was repeated three times independently with similar results. Source data are provided as a Source Data file.
