Rapid and high efficiency transformation of Chlamydomonas reinhardtii by square-wave electroporation

Chlamydomonas reinhardtii, the unicellular green algae, is the model organism for studies in various physiological processes and for bioindustrial applications. To explore the molecular mechanisms underlying physiological processes or to establish engineered cell lines, the exogenous DNA needs to be integrated into the genome for the insertional mutagenesis or transgene expression. However, the amount of selected marker DNA is not seriously considered in the existing electroporation methods for mutants library construction. Here, we reported a rapid-and-high-efficiency transformation technique for cell-walled strains using square-wave electroporation system. The final yield with this electroporation method was 2-6 x 10(3) transformants per mu g exogenous DNA for cell-walled strains in a strain-dependent manner. In general, this electroporation technique was the easy and applicable way to build a mutant library for screening phenotypes of interest.