A typical ligation with pYPKa is:

5µL insert 1µL water 1µL digested pYPKa vector 2µL buffer 1µL enzyme

Thsi could be simplified to:

5µL insert 1µL water 6µL LigationMastermix-2x

where the LigationMastermix-2x is 2 µL water 1 µL acetylated BSA (10 mg/ml) http://se.promega.com/resources/pubhub/enotes/shorten-the-ligation-time-for-the-pgem-t-vector-systems/ 2 µL 2 x ligation buffer 1 µL T4 DNA ligase (5U/µL)