PROTOPLAST PRODUCTION AND TRANSFORMATION OF MORPHOLOGICAL MUTANTS OF THE QUORN(R) MYCO-PROTEIN FUNGUS, FUSARIUM-GRAMINEARUM A3 5, USING THEHYGROMYCIN B RESISTANCE PLASMID PAN7-1/

A protocol for the generation of high yields of viable protoplasts has been developed for several highly branched (colonial) strains of the Quom(R) myco-protein fungus, Fusarium graminearum A3/5. Driselase was found to produce higher protoplast yields (ca 10(9) g(-1) wet weight) than the other lyric enzymes tested (Glucanex, Novozyme, beta-glucuron idase, Sigma lyric enzyme, or ICN lytic enzyme), although yields diffe red for the various strains. Protoplast regeneration frequencies of 25 -50% were observed when glucose (1.0 M) or sucrose (1.0 M) was used as the osmotic stabilizer. A highly branched strain of F. gramimearum CC 1-5, which grows better in submerged culture than the more sparsely br anched wild-type strain (P3/5) was transformed using the hygromycin B resistance plasmid pAN7-1.