In carbon and nitrogen metabolisms of higher plants

2-oxoglutarate is an important regulation effector.Some experiments have already showed that 2-oxoglutarate could promote enzymes of carbon and nitrogen metabolisms in roots of rice seedlings roots（experiment in vivo）

for example

HXK、GS、GOGAT and ICDH.To conform whether direct interaction between 2-oxoglutarate and these enzymes

we made enzyme extracts from rice seedling roots in normal culture condition（free 2-oxoglutarate）

and the different concentrations of 2-oxoglutarate were added to the reaction systems of the above enzymes

and determined their activities（experiment in vitro）

respectively.The results showed that the activities of GS

HXK were promoted by 2-oxoglutarate

but GOGAT and ICDH were not affected.This suggested that 2-oxoglutarate

which was neither their substrate nor their product

maybe as an effector of GS and HXK to promote their activities both in vivo and in vitro.