CEPHALOSPORIN-C PRODUCTION AND GENETIC-IMPROVEMENT OF THE FUNGUS ACREMONIUM-CHRYSOGENUM BASED ON MORPHOLOGICAL MUTANT ISOLATION

C-10 strain of the fungus Acremonium chrysogenum produced about 1.5 g/ l of cephalosporin C, a yield that was much lower than expected accord ing to the literature. This discrepancy, confirmed by exhaustive tests , showed that C-10 strain lost its high cephalosporin C production abi lity, probably due to genetic events. Strain. improvement, based on is olation of morphologically compact mutant colonies, confirmed that thi s is a useful procedure for isolation of strains with increased titer. About 2% of rested colonies produced significantly more cephalosporin C than the original strain.