Study of an artificial endoassociation between Saccharomyces cerevisiae and Escherichia coli.

The establishment of an artificial endoassociation between Escherichia coli (JC 5466, trp, his, recA 56, lac delta X 74, SpcR, harbouring the plasmid pRD1 which confers on it the capacity to produce penicillinase), and Saccharomyces cerevisiae (3.2, a, ade, ura, lys) was carried out in order to study its behaviour and stability. The pattern of protoplast reversion to whole cells, the penicillinase production capacity, the stability without selective pressure and the bacterial localization in the yeast cells, is described and discussed.