[Cyclosporin biosynthesis and dynamics of bioenergetic processes in cyclosporin-producing strain]

An attempt was made to show a correlation between definite bioenergetic parameters of the cells of the cyclosporine-producing culture and biosynthesis of cyclosporine. It was found that the three strains producing cyclosporine used in the study had an alternative cyanide-resistant pathway along with the classical cytochrome chain. In the strain forming only traces of the cyclopeptide during fermentation of the cyanide-resistant respiration constituted 60 to 80%. In the isogenic highly productive strains the cyanide-resistant respiration appeared to be markedly decreased beginning from the 1st day of fermentation and during the maximum biosynthesis of cyclosporine (on day 4 or 5 of fermentation) it reached zero. The ATP content in the cells of the highly productive strain, despite its decrease by the antibiotic biosynthesis peak, remained at a much higher level than that in the strain producing only traces of cyclosporine. A procedure for isolating functionally active mitochondria from the protoplasts was developed and a bioenergetic characterization of the mitochondria isolated from the strains with different antibiotic productions is presented.