ESTIMATION OF THE KINETIC CONSTANTS AND ELUCIDATION OF TRENDS IN GROWTH AND ERYTHROMYCIN PRODUCTION IN BATCH AND CONTINUOUS CULTURES OF SACCHAROPOLYSPORA-ERYTHRAEA USING CURVE-FITTING TECHNIQUES
Jf. Mcdermott et al., ESTIMATION OF THE KINETIC CONSTANTS AND ELUCIDATION OF TRENDS IN GROWTH AND ERYTHROMYCIN PRODUCTION IN BATCH AND CONTINUOUS CULTURES OF SACCHAROPOLYSPORA-ERYTHRAEA USING CURVE-FITTING TECHNIQUES, Enzyme and microbial technology, 15(8), 1993, pp. 657-663
The kinetics of erythromycin production were dependent on the identity
of the growth rate-limiting nutrient during batch cultures of Sacchar
opolyspora erythraea. Semilogarithmic linear regression provided a sin
gle estimate of growth rate during the exponential phase, but partial
cubic spline curve fit derivatives provided time-dependent specific gr
owth and production rate profiles. Non-growth-linked product formation
was observed when the medium was glucose- or phosphate-limited. Howev
er, growth-linked product formation was observed in a nitrate-limited
medium. The kinetics observed in nitrate-limited chemostat culture pro
vided evidence that Saccharopolyspora erythraea may be subject to nonc
ompetitive inhibition by a growth-linked product under these condition
s. A mathematical model was used to test this theory. The model simula
tion fitted the observed data very closely and was used to calculate e
stimates of the kinetic parameters involved: Yp/x[erythromycin/biomass
] = 1.98 x 10(-3); Yp/s[erythromycin/glucose] = 1.85 x 10(-3); k(i) =
1.56 mg l-1; k(s[glucose]) = 1.5 x 10(-2) mg ml-1; mu(max(chemostat))
= 0.066 h-1