The Role Of Lipoxygenase Pathway In The Elicitor -Induced Taxol Production In Taxus Chinensis Cell Cultures

Biotic elicitor treatment can largely increase the taxol production in Taxus species cellcultures and thus has become a very promising pathway for the industrial amplification ofcell culture model. Further evidence demonstrated that elicitor induced taxol productionmight be closely related to the plant defense reaction. Elicitor signal may induced taxolproduction by activating the signal transduction pathway in plant defense reaction andsynthesize some signal molecules that can activate the downstream taxol synthesis enzymesystem. Nowadays, because of its crucial roles in plant defense reaction, lipoxygenasepathway and its product jasmonic acid have been paid much more attention from scientistsaround the world. Therefore, we studied the relationship between the lipoxygenasepathway and elicitor induced plant defense reaction and the role of lipoxygenase in theelicitor induced taxol production. The result showed that: 1. Both fungal elicitor and methyl jasmonate could activate thelipoxygenase pathway. Lipoxygenase might be involved in the elicitor induced membraneperoxidation and linolenic acid was the main substrate for lipoxygenase; 2. Lipoxygenasepathway might be involved in the fungal elicitor induced taxol production and methyljasmonate, which is an important product of lipoxygenase pathway might also inducedtaxol production by activating the endogenous lipxoygenase pathway; 3. There might be atleast 49.18% lipoxygenase with enzyme activity are associated with the membrane. ThepH profile for lipoxygenase showed that the significant enzyme activity is mainly in theacidic reign and the highest peak is appeared at pH3.5. Although there are also two otherpeaks at pH6.0 and pH 9.0, there are much lower than the activity in the acidic reign. Therelative molecular weight of lipoxygenase in the Taxus chinensis is about 93 000 Dalton.