Use of a series of chemostat cultures to isolate 'improved' variants of the Quorn mycoprotein fungus, Fusarium graminearum A3/5.
Variants (designated A23-S and A24-S) of the Quorn myco-protein fungus, Fusarium graminearum A3/5 were isolated from a series of glucose-limited cultures grown at a dilution rate of 0.18 h-1 for a combined total of 109 d. These variants had unchanged mycelial morphologies but, when grown in mixed culture with the parental strain (A3/5) in glucose-limited chemostat culture at 0.18 h-1, A23-S and A24-S had selection coefficients of 0.013 and 0.017 h-1, respectively, and supplanted A3/5. When a monoculture of A23-S was grown in a glucose-limited culture at a dilution rate of 0.18 h-1, the appearance of highly branched (so-called colonial) mutants was delayed compared with their appearance in chemostat cultures of the parental strain. Furthermore, when a monoculture of A24-S was grown in glucose-limited culture at 0.18 h-1, the appearance of colonial mutants was delayed even further. Thus, it is possible to isolate advantageous (relative to A3/5) variants of F. graminearum A3/5 which have unchanged mycelial morphologies, but in which the appearance of colonial mutants is delayed.
Wiebe
M G
MG
School of Biological Sciences, University of Manchester, UK.
Robson
G D
GD
Oliver
S G
SG
Trinci
A P
AP
D003513:Cycloheximide / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D005656:Fungal Proteins; D005670:Fusarium / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D014644:Genetic Variation; D008828:Microbiological Techniques; D009154:Mutation; D012641:Selection, Genetic
D005656:Fungal Proteins; D003513:Cycloheximide