Sortase A, S. aureus (SrtA) is found in many Gram-positive bacteria and facilitates the recruitment of cell surface proteins. It plays a crucial role in the attachment of various molecules on the cell surface.

The product can be diluted with sterile purified water to a concentration of 0.5 μg/μL for use. Peptide reaction system preparation (30 μL system) includes: Test group: 5 μL Srt3 (1 mM), 5 μL Srt4 (1 mM), 5 μL Sortase A (0.5 μg/μL), 10 μL 3× reaction Buffer, and 5 μL ddH2O; Control group: 5 μL Srt3 (1 mM), 5 μL Srt4 (1 mM), 20 μL ddH2O. Prepare the corresponding control and test groups as per the table, mix the test group reagents evenly, centrifuge, and react at 30°C for 1-3 hours. After the reaction, synchronize SDS-PAGE electrophoresis for both groups. Notes: 3× reaction Buffer consists of 100 mM Tris-HCl 7.5, 50 mM CaCl2, and 20 mM DTT. The synthetic peptides used for the performance reaction are as follows: SrtA-3 YGVRLCGREFIRAVIFTCGGSRWRRKGGLPRTGG (34) and SrtA-4 GGGGSGGRRSRRSRQDLQTLCCTDGCSMTDLSALC (35). When synthesizing peptides, it is recommended to divide them into small tubes and dissolve them in sterile purified water, preparing and using them immediately.