Abstract: OBJECTIVE To investigate the location of the N-terminal of the Salmonella enterica serovar typhimurium small heat shock protein AgsA in its oligomers, in order to provide clinical reference for the treatment. METHODS A His-tag was added on the N or the C-terminal of AgsA protein, then the binding capacities of the two recombinant proteins with Ni-NTA agarose were measured to compare how much the N- and the C-terminal of AgsA was exposed in solution. RESULTS The gel exclusion chromatography analysis and chaperone-like activity assay showed that the added His-tag neither affected the oligomeric state of AgsA, nor affected the chaperone-like activity of AgsA. By comparing the binding capacity of the two His-tag added proteins with Ni-NTA agarose, we found that the C-terminal of AgsA protein was far greater exposed in solution than its N-terminal. CONCLUSION AgsA-N-His6 with Ni-NTA agarose binding capacity is far less than AgsA-C-His6, which suggests that the N-terminal of AgsA is buried within its oligomers.