The pTYB1 is an E. coli vector created for fusion protein expression and purification. A target gene can be inserted into the the ORF by use of the MCS upstream of the Sce VMA intein. The NdeI site in the MCS has the initiator sequence ATG that enables translation of the ORF. The chitin-binding domain(CBD) downstream of the intein results in a target protein-intein with C-terminal chitin beads that facilitate protein purification. Release of the protein is induced by the thiol cleavage activity of the intein.