earticle

영어

Klebsiella pneumoniae naturally produces 2,3-butanediol (2,3-BDO) in a large amount, so it is one of the most extensively studied microorganism for 2,3-butanediol production. However, 2,3-BDO production of K. pneumoiae strongly depends on various culture conditions, so defining the optimal culture condition is one of the most important step in understanding the 2,3-BDO biosynthesis. In this study, various tests were done to find the optimal culture conditions for a newly constructed K. pneumoniae strain. First, in order to minimize the pathogenicity, the wabG genewhich is the core gene in lipopolysaccharide biosynthesis of K. pneumoniae was deleted. Second, in order to find the optimal culture condition of K. pneumoniae, carbon concentration test was carried out. Carbon concentration test (10 g/L, 20 g/L, 30 g/L, 40 g/L, 50 g/L) was carried out in order to select the optimal carbon concentration for this particular strain, respectively. As a result, when the carbon source concentration increased from 10 g/L to 30 g/L, the cell growth increased as the carbon source concentration increased (max dry cell weight = 2.34g/L, at Glucose 30g/L). Furthermore, in order to find the limiting factor for the cell growth and 2,3- BDO production, the elementary composition of K. pneumoniae was calculated (Carbon : Nitrogen = 4 : 1). But, even though the nitrogen source was increased due to the carbon concentration, the carbon consumption rate, cell growth, and 2,3-BDO production did not increase. It was concluded that the limiting factor for the K. pneumoniae cell growth or 2,3-BDO production was not the concentration of carbon or nitrogen, but some other factors such as pH or temperature, and further experiments are on-going to define these limiting factors.