pPIC3.5K

Multiple copy integration of recombinant genes in Pichia has been demonstrated to 

increase expression of the desired gene in some cases （Brierley, et al., 1994; Clare, et al., 

1991a; Cregg, et al., 1993; Romanos, et al., 1991; Scorer, et al., 1993; Scorer, et al., 

1994; Thill, et al., 1990; Vedvick, et al., 1991）. The two vectors included in this kit 

allow isolation and generation of multicopy inserts, either by in vivo or in vitro methods, 

in order to test whether increasing the copy number of your recombinant gene will lead to 

a subsequent increase in protein expression. The in vivo method utilizes hyper-resistance 

to GeneticinÆ

 （G418 sulfate） to screen for possible multicopy inserts, while the in vitro

method produces tandem inserts of your gene by ligation.