基因工程菌培养过程中乙酸的积累及其对工程菌生长和产物表达的影响

在rIL-2工程菌K802(pLY-4)高密度培养中发现培养液中有大量代谢副产物乙酸积累,乙酸的存在对工程菌的生长和产物的表达均有明显的抑制作用,这种抑制作用是制约工程菌高密度培养的重要因素,为了减小这种抑制作用,研究了培养基pH与乙酸抑制作用的关系,发现适当提高培养基pH值,能有效地减小乙酸的抑制作用;高密度培养时,提高培养基的pH后,虽然仍有大量乙酸积累,但产物的表达水平和菌密度都有一定的提高

Effects of Acetic Acid Accumulation on the Growth and Product Expression Level of Recombinant E. coli

Fermentation studies were performed on an Esclienchui coli eulture that carries a recombmani plasimd com posed of an arnpicillm-resistant gene, a temperature regulated PI.PK promoter, and an interleukm gem -The objective was to find the way to decrease the inhibition of acetic acid which was found accumulating in the na-dia in high-cell density culture. The response of the inhibition on the media pH was studied. The results suggested the inhibition could be decreased by regulating the media pH appropriately. In high-cell density culture, tin specific expression level and cell density was increased by raising the media pH. although there was much acetu acid accumulation too.