Staphylococcus aureus Sortase A-Mediated Incorporation of Peptides: Effect of Peptide Modification on Incorporation
Fig 1
Schematic representation of the C-terminal region of FnBP precursor and synthetic substrates used in this study.
1: the minimal substrate used, containing the SrtA recognition motif LPETG only (designated A). 2: the scrambled version of substrate 1, EGTLP. Native: the sorting motif of the FnBP precursor of S. aureus, containing the SrtA recognition motif (A), a hydrophobic domain (B) and a positively charged region (C). The full sequences of the separate regions are depicted under the blocks. Domain (A) and (B) are linked via a hydrophilic spacer GEESTNK [24]. The N-terminus and the C-terminus are indicated with * and # respectively. 3: schematic representation of substrate 3, based on the complete sorting signal of the FnBP precursor. 4: schematic representation of substrate 4, in which domain (B) and (C) are interchanged. 5: schematic representation of substrate 5, in which domain B is removed. 6: schematic representation of substrate 6 containing domain (A), truncated domain (C) and a C-terminal tryptophan. 7: schematic representation of substrate 7 containing domain (A), with glutamate (E) substituted for methionine (M). 8: schematic representation of substrate 8, composed of substrate 7 with its N-terminus linked to vancomycin. 9: schematic representation of substrate 9, the scrambled version of substrate 8, with an MGTLP motif instead of an LPMTG motif. 10: schematic representation of substrate 10, composed of substrate 7 with its C-terminus linked to vancomycin. 11: schematic representation of substrate 11, composed of substrate 5 with its N-terminus linked to vancomycin. All substrates were at the N-terminus labelled with a FITC group.