Neomycin resistance as a dominantly selectable marker for transformation of the zygomycete Absidia glauca

Summary A plasmid (pAmN61) containing the NPT II structural gene (neomycin phosphotransferase) fused to the N-terminal region of a homologous actin gene was used for the transformation of Absidia glauca protoplasts. Neomycin resistant transformants could be selected for on complete medium containing 1.2 mg/ml neomycin sulfate. The physical presence of plasmid DNA in Absidia glauca was demonstrated by retransformation into Escherichia coli and by Southern blot analysis. No integration of plasmid DNA at either one of the two actin loci was observed; Southern blot experiments provide evidence that pAmN61 is autonomously replicated in Absidia glauca.