재조합 대장균을 이용한 1,3-Propandiol과 Organophosphorus Hydrolase생산공정 개발

Abstract

Developments of sustainable technologies for the production of renewable materials from agricultural feedstock are rapidly growing issues due to upsurging oil price in world market. More than thousand tons of polyester are produced every hour in the world and polyethylene terephthalate (PET) occupy the major fraction of this amount. 1,3-Propanediol (PDO) is the key intermediate for the synthesis of PET. The recombinant E. coli produced 1,3-PD from glucose and the production of 1,3-PDO was increased with feedback glucose concentration using fedbatch fermentation. The maximum 1,3-PDO concentration produced was 43 g/l after 60 hrs fermentation. The glycerol production was minimized by controlling the glucose concentration less than 1 g/L. The development of a fedbatch fermentation process for the production of organophosphorus hydrolase (OPH) by E. coli pET812 is described in this manuscript. Originally, the maximum OPH concentrations attained by batch fermentation were as low as 4 x 105 U/l because cell growth and OPH production were inhibited by a high concentration of initial glucose. To develop a fedbatch fermentation process for obtaining higher concentrations OPH, highly concentrated glucose solution (500 g/l) was added intermittently or continuously to increase the carbon source concentration. Eventually, 3.2 x 106 U/l of OPH was produced with fedbatch fermentation in 24 hrs. This was 8 times higher than that with conventional batch fermentation. A total concentration of 399-441 mg/l of OPH was produced, which was 4 times higher than that reported when using E. coli. Nearly half (44 %) of the produced OPH was secreted into the culture solution.