Abstract
Recently, a stable nuclear transformation technique was established with two marine diatoms Phaeodactylum tricornutum and Thalassiosira pseudonana . However each system accommodates only one selection system, which limits the capacity of diatom transformation systems. The purpose of this research is to isolate auxotrophic mutants of marine diatoms and to establish the phenotypic complementation system of the genetic lesion. P. tricornutum and T. pseudonana were mutagenized by 1mg/mL ENU ( N -ehtyl- N - nitrosourea) solution for 30min. Then, they were cultured on ASW (artificial sea water) agar medium containing 0.6mM 5-fluoro orotic acid (5-FOA) and 0.5mM uracil. 5-FOA resistant clones were innoculated to several ASW agar plate containing 1.8mM 5-FOA and 0.5mM uracil. As a result, a few clones of uracil auxotrophic mutants of P. tricornutum was isolated. The results from characterization of these mutant will be discussed.
