The Molecular Mechanism Of Glutamine Synthase(Gs) On Aspergillus Flavus

Aspergillus flavus is a kind of filamentous pathogenic fungus for crops and its secondary metabolite-aflatoxin is a strong carcinogen threaten human health.To study the regulated protein in A.flavus will provide the foundation in control work of this kind of fungi.Glutamine synthetase(Gs)is a key enzyme involved in the process of ammonia assimilation during complicated nitrogen metabolism.In this study,we found that Glutamine synthetase(Gs)of Aspergillus flavus play an important role in the growth,the production of spore and sclerotium,toxin synthesis.This research project mainly contains the following contents:(1)We knocked out gs gene in Aspergillus strains by the method of homologous recombination.?Gs strain showed different phenotypes with WT in growth,spore production,to produce and toxings gene impacts the growth and development of Aspergillus.(2)Recombinant protein was expressed,purified and crystallized.It make some preparation for measuring the activity of Gs protein in vit(3)This study measured the activity of Gs protein in vitro and the inhibitory effect of CAMP and DL-Ser on the enzyme activity.(4)Two kinds of chemical molecule,CAMP and DL-Ser can inhibit not only activity of Gs,but also the the growth of Aspergillus flavus.In this study,we found that Gs in Aspergillus were closely related to the growth of Aspergillus flavus,and CAMP,DLl-ser had a significant inhibitory effect on Gs protein and A.flavus growth.These results of research can provide insight for preventing the contamination of crops and human health.