ELECTROPHORETIC KARYOTYPING OF YEASTS, AND SOUTHERN BLOTTING USING WHOLE CHROMOSOMES AS TEMPLATES FOR THE PROBE PREPARATION

Abstract

The technique of Contour-clamped Homogenous Electric Field (CHEF) gel electrophoresis has been used to separate intact chromosomal DNA of different species of the yeast genera Saccharomyces and Zygosaccharomyces. Various strains of the same species had similar chromosomal band patterns. However, differences between individual bands indicated that strain-specific chromosome length polymorphism is common in these organisms.
To test conspecificity, a new, DNA-DNA hybridization technique was developed using individual whole chromosomes as templates to prepare randomly primed, radioactive probes. Under our conditions of stringency, species-specific hybridization reactions were achieved with these probes. The method is an efficient tool to study the genetic diversity of a given yeast species. Also, it can assist yeast species identification.