[Effect of inoculum parameters on the specificity of secondary synthesis in cultures producing novobiocin and mycoheptin]. / Vliianie kharakteristik posevnogo materiala na napravlennost' vtorichnogo sinteza produtsentov novobiotsina i mikogeptina.

The impact of the vegetative inoculum parameters on specificity of the secondary synthesis in the cultures producing novobiocin and mycoheptin was studied. During the study the fermentation conditions were varied by using the vegetative inoculum differing in the respiration rate after its transfer to the fermentation medium. To show the decisive role of the inoculum parameters in regulation of the specificity of the secondary synthesis, the dynamics of accumulation of certain metabolites forming from glucose along with the main antibiotic and the activity of the key enzymes of the carbohydrate metabolism during the culture growth in the fermentation media were studied. It was found that the specificity of the secondary synthesis with respect to certain metabolites was defined by the intensity of carbohydrate metabolism, i. e. the ratio of the activity of enzymes of glycolysis and the pentosephosphate pathway. In this regard, the inoculum with the maximum respiration rate in an amount of 10 to 20 per cent promoted the highest productivity of the mycelium by the synthesis of novobiocin and mycoheptin while the rate of accumulation of fatty acids, carbohydrates and phenol compounds (for Streptomyces spheroides) and mycopentene (for Streptoverticillium mycoheptinicum) decreased.

[Study of biosynthesis of mycoheptin, mycopentene and fatty acids by Streptoverticillium mycoheptinicum strain 255 in various conditions of its cultivation]. / Issledovanie biosinteza mikogeptina, mikopentena i zhirnykh kislot v razlichnykh usloviiakh kul'tivirovaniia Streptoverticillium mycoheptinicum shtamm 255.

The effect of the fat content in the medium for cultivation of Streptoverticillium mycoheptinium-255 and the effect of glucose intake on the rate of carbohydrate utilization and intensity of incorporation of labeled sodium acetate and propionate to mycoheptin, mycopentene and fatty acids were studied. It was shown that a lower fat content in the medium in comparison with the optimal one resulted in intensification carbohydrate catabolism during an idiophase, increased production rates of mycopentene, an accompanying antibiotic, and fatty acids and a decrease in the heptaene/pentaene ratio. The optimal contents of the oil in the medium provided a decrease in the rate of the carbohydrate consumption and preferable production of the required antibiotic or mycoheptin accompanied by a decrease in the synthesis rate of mycopentene and fatty acids.