DIFFERENTIATION OF BREWERY YEAST STRAINS BY DNA-FINGERPRINTING

A reliable and reproducible non-radioactive DNA fingerprinting techniq ue has been used to differentiate between twelve production brewery ye ast strains. The method comprises total DNA preparation from the yeast strains, enzymatic digestion of the DNA and analysis of the DNA fragm ents by ''probing'' with known DNA labelled with the plant steroid dig oxigenin. A range of probes and several enzymes have been investigated . A successful combination is the restriction endonuclease Hind III an d a probe derived from Ty1 (a yeast transposable element). The main ad vantages of this method are its unambiguity, reproducibility and suita bility for routine brewery QC use.