<p>The PST constructs were expressed in <i>E. coli</i> AD202 followed by cell disruption and centrifugation. The soluble (Sup) and insoluble (Pel) fractions were analyzed by SDS-PAGE and Coomassie Blue staining. Bands corresponding to the predicted sizes of the protein variants were observed (indicated with an asterisk). The increased intensity of the bands of the MalE-fusions indicated increased expression compared to the non-fusion protein. Furthermore, the truncated protein (MalE-Δ20PST<sub>Mh</sub>) variant demonstrated the best solubility.</p