The effect of temperature on bacterial degradation of EDTA in pH-auxostat
The effect of temperature on bacterial degradation of EDTA in pH-auxostat
复制标题
DOI:
10.1007/s11274-006-9162-0
复制
发表时间:
2006-05
影响因子:
4.1
通讯作者:
I. Minkevich;A. Satroutdinov;E. Dedyukhina;T. I. Chistyakova;E. Kaparullina;A. Koshelev;O. Okunev
中科院分区:
文献类型:
--
作者:
I. Minkevich;A. Satroutdinov;E. Dedyukhina;T. I. Chistyakova;E. Kaparullina;A. Koshelev;O. Okunev
The effect of temperature on the maximum specific growth rate and the cell yield was studied during cultivation of two bacterial strains (LPM-4 andPseudomonassp. LPM-410) on EDTA under unlimited cell growth conditions in a pH-auxostat. Both strains displayed linear dependence of reciprocal biomass yield against reciprocal specific growth rate, from which the values of rate of substrate expenditure for cell maintenance and the “maximum” yield (i.e., hypothetical yield without cell maintenance processes) were estimated. Analysis of the maximum yield values based on mass–energy balance theory suggested that oxidation of the carboxylic acid side chains of EDTA by a monooxygenase had zero or low energetic efficiency. An Arrhenius equation with different values of Arrhenius parameters within different temperature ranges gave a good fit with the temperature dependence of both growth rate and biomass yield. Specific growth rates of both strains showed a more pronounced temperature dependence than did the cell yields. A possible kinetic mechanism was suggested which might be responsible for the modes of the temperature dependences of specific growth rate and yield that were found. The mechanism is based on a hypothetical key substance governing the metabolic flows, which is formed in a zero-order reaction and destroyed in a first-order reaction, both rate constants depending on temperature according to the Arrhenius law.