Production of Toxoplasma gondii Recombinant Antigens in Genome-Edited Escherichia coli

Toxoplasmosis is a widespread zoonosis with an impact on immunocompromised people and critical in pregnant women because of its transmission to the fetus. Recombinant Toxoplasma gondii antigens produced in Escherichia coli are useful for antibody detection in patient's blood. The aim of the study was to evaluate the feasibility of deriving chromosome-edited E. coli clones producing T. gondii antigens. Here, we present the CRISPR-Cas9 facilitated editing of the E. coli genome to produce SAG2 and GRA2 T. gondii antigens. Moreover, we have derived a clone that produces both proteins and an additional clone producing a novel fusion protein, SAG2-GRA2. These proteins, bearing His-tag, can be easily purified and are useful to detect anti-Toxoplasma antibodies in human blood. We conclude that it is feasible to edit the E. coli chromosome to produce T. gondii antigens that are bound by antibodies present in people affected by toxoplasmosis.