An enrichment method for heme-less mutants of Saccharomyces cerevisiae based on photodynamic propeties of Zn-protoporphyrin

Abstract
A new and widely applicable technique has been elaborated for enrichment of mutants of Saccharomyces cerevisiae deficient in porphyrin and heme synthesis. The method is based on selective photooxidative killing of the wild-type cells, sensitized by Zn-protoporphyrin synthesized and accumulated in wild-type cells under defined conditions. Using a single cycle of selection, heme-deficient mutants have been obtained with a frequency of 2–2.3%.