The vector pKLAC1 directs high-level expression of a recombinant protein from the yeast Kluyveromyces lactis and is part of the K. lactis Protein Expression Kit (NEB #E1000). pKLAC1 can be used for either intracellular or secreted protein expression. SacII or BstXI linearized pKLAC1 integrates into the LAC4 locus of the K. lactis genome upon transformation of K. lactis GG799 Competent Cells (NEB #C1001).
Vector pKLAC1 contains the strong K. lactis PLAC4-PBI promoter (1), DNA encoding the K. lactis α-mating factor (α-MF) secretion domain (for secreted expression), a multiple cloning site (MCS), the K. lactis LAC4 transcription terminator (TT), and a fungal acetamidase selectable marker gene (amdS) expressed from the yeast ADH2 promoter (PADH2). An E. coli replication origin (ori) and ampicillin resistance gene (ApR) are present for propagation of pKLAC1 in E. coli. NEB 5-alpha Competent E. coli (High Efficiency) (NEB #C2987), NEB 5-alpha Electrocompetent E. coli (NEB #C2989) and NEB 5-alpha Competent E. coli (Subcloning Efficiency) (NEB #C2988) are all recommended for propagation and subcloning of this vector.
- PLAC4-PBI promoter does not express in E. coli allowing toxic genes to be cloned prior to their expression in yeast.
- Convenient MCS lies downstream of α-MF secretion domain and PLAC4-PBI promoter.
- Acetamidase expression for non-antibiotic selection in K. lactis.
- Ampicillin resistance for propagation in E. coli.