Secretion of β-lactamase from K. lactis using pEPS1, a convenient episomal vector designed for the secretion of foreign proteins

A convenient shuttle vector that enables high level secretion of proteins from Kluyveromyces lactis has been developed. The vector, pEPS1, contains a unique cloning site that allows the construction, in a single ligation step, of episomal plasmids capable of directing secretion of foreign gene products from K. lactis. As an example we demonstrate the production of β-lactamase and determine optimal conditions for its secretion into the culture media.