Abstract:

In this paper , the ZZ domain from Stαphylococcus aureus was first successfully displayed on the cell sur-face of yeast Saccharomyces cerevisiae by yeast cell-surface display systems. Next , rabbit IgG was purified from the serum by using the cells displaying ZZ. Then , yeast display vector plCZZ was constructed by amplifying the geneencoding ZZ on pEZZ18 template via PCR and by inserting the ZZ gene into shuttle vector plCAS via restriction enzyme digestion. Moreover , the constructed plCZZ was introduced in Saccharomyces cerevisiae MT8-l. It is indicated from the nucleic acid electrophoretic map that ZZ gene is successfully integrated into the genome. Moreover, the microscope images reveal that , after the immunofluorescence labeling of the cultured recombinant cells , ZZ proteins were successfully displayed on the cell surface. This observation is further verified by flow cytometry , which convinces the protein display of 80. 4% of cells. Finally ，the IgG from the serum was absorbed by the yeast cells displaying ZZ proteins , and the elution was analyzed by means of SDS-PAGE and westem blot. All the results show that the rabbit IgG isolated by cells displaying ZZ is purer than that of standard sample.

Key words: Saccharomyces cerevisiae, ZZ domain from Staphylococcus αureus, immunofluorescence labeling, flow cytometry